IR3889MTRPBF [INFINEON]

OptiMOS™ IPOL 30 A single – voltage synchronous buck regulator;
IR3889MTRPBF
型号: IR3889MTRPBF
厂家: Infineon    Infineon
描述:

OptiMOS™ IPOL 30 A single – voltage synchronous buck regulator

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IR3889  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Features  
Single 4.3 V to 17 V application or Wide Input Voltage Range from 2.0 V to 17 V with an External VCC  
Precision Reference Voltage (0.8 V +/- 0.5%)  
Enhanced Fast COT Engine Stable with Ceramic Output Capacitors  
Optional Forced Continuous Conduction Mode and Diode Emulation for Enhanced Light Load Efficiency  
Programmable Switching Frequency from 600 kHz to 2 MHz  
Monotonic Start-Up with Four Selectable Soft-Start Time & Enhanced Pre-Bias Start-Up  
Thermally Compensated Internal Over Current Protection with Four Selectable Settings  
Enable input with Voltage Monitoring Capability & Power Good Output  
Thermal Shut Down  
Operating Temp: -40 °C < Tj < 125 °C  
Small Size: 5 mm x 6 mm PQFN  
Halogen-free and RoHS2 Compliant with Exemption 7a  
Potential applications  
Server Applications  
Storage Applications  
Telecom & Datacom Applications  
Distributed Point of Load Power Architectures  
Product validation  
Qualified for industrial applications according to the relevant tests of JEDEC47/20/22  
Description  
The IR3889 is an easy-to-use, fully integrated dc - dc Buck regulator. The onboard PWM controller and OptiMOS™  
FETs with integrated bootstrap diode make IR3889 a small footprint solution, providing high-efficient power  
delivery. Furthermore, it uses a fast Constant On-Time (COT) control scheme, which simplifies the design efforts  
and achieves fast control response.  
The IR3889 has an internal low dropout voltage regulator, allowing operations with a single supply. It can also  
operate with an external bias supply, with an extended operating input voltage (PVin) range from 2.0 V to 17 V.  
The IR3889 is a versatile regulator, offering programmable switching frequency from 600 kHz to 2 MHz, four  
selectable current limits, four selectable soft-start time, Forced Continuous Conduction Mode (FCCM) and Diode  
Emulation Mode (DEM) operation.  
It also features important protection functions, such as pre-bias start-up, thermally compensated current limit,  
over voltage and under voltage protection, and thermal shutdown to give required system level security in the  
event of fault conditions.  
Final Datasheet  
www.infineon.com  
Please read the Important Notice and Warnings at the end of this document  
page 1 of 50  
V2.7  
2022-4-4  
 
 
 
 
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Table of contents  
Table of contents  
Features ........................................................................................................................................ 1  
Potential applications..................................................................................................................... 1  
Product validation.......................................................................................................................... 1  
Description .................................................................................................................................... 1  
Table of contents............................................................................................................................ 2  
1
2
3
4
5
Ordering information ............................................................................................................. 4  
Functional block diagram........................................................................................................ 5  
Typical application diagram .................................................................................................... 6  
Pin descriptions ..................................................................................................................... 7  
Absolute maximum ratings ..................................................................................................... 9  
6
Thermal Characteristics.........................................................................................................10  
6.1  
Thermal Characteristics........................................................................................................................10  
7
7.1  
7.2  
Electrical specifications .........................................................................................................11  
Recommended operating conditions...................................................................................................11  
Electrical characteristics.......................................................................................................................12  
8
Typical efficiency and power loss curves..................................................................................15  
PVin = Vin = 12 V, fsw = 600 kHz.............................................................................................................15  
PVin = Vin = 12 V, fsw = 800 kHz.............................................................................................................16  
PVin = Vin = 12 V, fsw = 1000 kHz...........................................................................................................17  
PVin = Vin = VCC = 5 V, fsw = 600 kHz.....................................................................................................18  
8.1  
8.2  
8.3  
8.4  
9
Thermal De-rating curves.......................................................................................................19  
RDS(ON) of MOSFET Over Temperature ........................................................................................20  
Typical operating characteristics (-40 °C Tj +125 °C)..............................................................21  
10  
11  
12  
Theory of operation...............................................................................................................24  
Fast Constant On-Time Control ............................................................................................................24  
Enable ....................................................................................................................................................24  
FCCM and DEM Operation.....................................................................................................................25  
Pseudo Constant Switching Frequency................................................................................................25  
Soft-start................................................................................................................................................26  
Pre-bias Start-up ...................................................................................................................................27  
Internal Low - Dropout (LDO) Regulator...............................................................................................27  
Over Current Protection (OCP) .............................................................................................................28  
Under Voltage Protection (UVP) ...........................................................................................................29  
Over Voltage Protection (OVP)..............................................................................................................29  
Over Temperature Protection (OTP) ....................................................................................................30  
Power Good (PGood) Output ................................................................................................................30  
Minimum On - Time and Minimum Off - Time ......................................................................................31  
Selection of Feedforward Capacitor and Feedback Resistors.............................................................31  
Resistors for Configuration Pins ...........................................................................................................32  
12.1  
12.2  
12.3  
12.4  
12.5  
12.6  
12.7  
12.8  
12.9  
12.10  
12.11  
12.12  
12.13  
12.14  
12.15  
13  
Design example.....................................................................................................................33  
Enabling the IR3889...............................................................................................................................33  
Programming the Switching Frequency and Operation Mode............................................................33  
Selecting Input Capacitors....................................................................................................................33  
Inductor Selection.................................................................................................................................34  
13.1  
13.2  
13.3  
13.4  
Final Datasheet  
2 of 50  
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2022-4-4  
 
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Table of contents  
13.5  
13.6  
13.7  
13.8  
13.9  
Output Capacitor Selection ..................................................................................................................34  
Output Voltage Programming...............................................................................................................35  
Feedforward Capacitor .........................................................................................................................35  
Bootstrap Capacitor..............................................................................................................................35  
Vin, VCC/LDO and VDRV bypass Capacitor ...........................................................................................35  
14  
14.1  
14.2  
Application Information.........................................................................................................36  
Application Diagram..............................................................................................................................36  
Typical Operating Waveforms...............................................................................................................36  
15  
15.1  
15.2  
Layout Recommendations......................................................................................................39  
Solder Mask ...........................................................................................................................................43  
Stencil Design ........................................................................................................................................44  
16  
Package ...............................................................................................................................45  
Marking Information .............................................................................................................................45  
Dimensions............................................................................................................................................45  
Tape and Reel Information ...................................................................................................................47  
16.1  
16.2  
16.3  
17  
18  
Environmental Qualifications .................................................................................................48  
Evaluation Boards and Support Documentation .......................................................................49  
Revision history.............................................................................................................................50  
Final Datasheet  
3 of 50  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Ordering information  
1
Ordering information  
1.  
Ordering Information  
Sales Product Name  
IR3889MTRPBF  
Package Type  
Standard Pack Form and Qty  
Orderable Part Number  
QFN 5 mm x 6 mm  
Tape and Reel  
5000  
IR3889MTRPBFAUMA1  
IR3889MTRPBF  
A1  
Designator  
Packing type  
Tape & Reel  
Dry  
Moisture  
protection packing  
UM  
Packing size  
330 mm  
Halogen Free  
RoHS compliant  
Total lead free  
Yes  
Yes  
No  
A
29  
35 34 33 32 31 30  
36  
1
2
3
4
5
6
28  
ILIM  
NC  
En  
PGood  
Vin  
27  
26  
BOOT  
25  
VCC/LDO  
PHASE  
24 PVin  
VDRV  
GATEL  
37  
GATEL  
23  
22  
21  
20  
19  
PVin  
7
PGND  
PGND  
PGND  
PGND  
PVin  
PVin  
PVin  
PGND  
8
9
10  
11 12  
15  
17  
13  
16  
14  
18  
SW SW SW SW SW SW SW SW  
Figure 1 Package Top View  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Functional block diagram  
2
Functional block diagram  
VCC/LDO  
VDRV  
AGND  
PGood  
Vin  
AGND  
POR  
UVP  
Threshold  
UVP OTP  
+
-
VCC  
LDO  
EN  
Fault  
AGND  
BOOT  
PVin  
OVP  
+
-
Hysteresis  
OVP  
Threshold  
Turn-on Delay  
PGood  
Prebias  
Fault  
Q
S
HDrVin  
HDrv  
Q
R
+
-
PGood  
Threshold  
Hysteresis  
PHASE  
SW  
POR  
+
-
VCC  
4.0V  
Hiccup  
OVP  
GATE  
DRIVE  
LOGIC  
POR  
VDRV  
OTP  
En  
+
-
Fault  
1.2V  
LDrVin  
LDrv  
PWM  
PWM  
COMP  
SS  
SOFT  
START  
SS/Latch  
+
ADAPTIVE  
ON-TIME  
GENERATOR  
SET  
-
ZC  
-
+
PGND  
Zero Cross  
DETECTION  
PGND  
SW  
FB  
GATEL  
RAMP  
GENERATOR  
OCP  
OVP  
Latch Off  
Floor  
GENERATOR  
+
Hiccup  
-
+
VSENM  
S
Q
UVP  
VREF  
R
TON/  
MODE  
SW  
20ms  
Delay  
ILIM  
Figure 2 Block diagram  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Typical application diagram  
3
Typical application diagram  
PVin  
Enable  
PVin  
Vin  
EN  
BOOT  
VCC/LDO  
VDRV  
PHASE  
Vo  
SW  
PGood  
NC  
0.1uF  
PGood  
IR3889  
GATEL  
SS/Latch  
FB  
TON/MODE  
ILIM  
Cff  
VSENM  
PGND NC NC  
NC  
AGND  
RFB1  
RFB2  
Figure 3 IR3889 basic application circuit  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Pin descriptions  
4
Pin descriptions  
Note:  
I = Input, O = Output  
Pin#  
Pin Name  
I/O  
Type  
Pin Description  
Connecting a resistor to a quiet ground to set the Over  
Analog Current Protection (OCP) limit. Four user selectable OCP  
limits are available.  
1
ILIM  
I
Power Good status output pin is open drain. Connect a pull  
Analog up resistor from this pin to VCC or to an external bias voltage,  
e.g. 3.3 V.  
2
PGood  
Vin  
O
I
Input voltage for an Internal LDO. A 4.7 µF capacitor should  
be connected between this pin and PGND. If an external  
3
Power  
supply is connected to VCC/LDO pin, this pin should be  
shorted to VCC/LDO pin and a 10 µF ceramic capacitor can be  
shared with Vin and VCC/LDO pin.  
Output of the internal LDO or input for an external VCC  
voltage. A 2.2 µF - 10 µF ceramic capacitor is recommended  
to use between VCC, VDRV and the Power ground (PGND).  
Input bias for the internal driver. It should be shorted to  
VCC/LDO pin on the PCB. A 2.2 µF - 10 µF ceramic capacitor is  
recommended to use between VDRV, VCC/LDO and the  
Power ground (PGND).  
4
5
VCC/LDO  
VDRV  
I/O  
I
Power  
Power  
Gate of Low-side FET. This pin can be used to monitor the  
Analog gate signal of LS FET. No external components should be  
connected to it.  
Power Ground. Must be connected to the system’s power  
Ground ground plane. PGND and AGND are internally connected via  
the lead frame.  
6, 37  
GATEL  
PGND  
I
7, 8, 9, 10,  
19  
-
11, 12, 13,  
14, 15, 16,  
17, 18  
SW  
PVin  
O
I
Power  
Power  
Switch Node. Connect these pins to an output inductor.  
20, 21, 22,  
23, 24  
Input supply for the power stage.  
Source of High-side FET. Connect a bootstrap capacitor  
25  
26  
PHASE  
O
Analog between this pin and BOOT pin. A high temperature (x7R) 0.1  
µF or greater value ceramic capacitor is recommended.  
Supply voltage for the high side driver. Connect this pin to  
the PHASE pin through a bootstrap capacitor. For PVin above  
Analog 14 V, a resistor (e.g., 1 Ω~ꢀ Ωꢁ is recommended in series with  
the bootstrap capacitor to control the slew rate of the SW  
node rising edge.  
BOOT  
I
27  
29  
En  
I
I
Analog Enable pin to turn the IC on and off.  
Multi-function pin. Connect a resistor to a quiet ground to  
select Soft-Start time from 4 options. This pin also selects  
latched-off Over Voltage Protection (OVP) or non-latched  
SS/Latch  
Analog  
OVP.  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Pin descriptions  
Pin#  
Pin Name  
I/O  
Type  
Pin Description  
Output voltage feedback pin. Connect this pin to the output  
Analog of the regulator via a resistor divider to set the output  
voltage.  
30  
FB  
I
This pin provides the return connection for a pseudo remote  
voltage sensing. The feedback resistor divider should be  
connected to this pin. It is also used as ground for the  
31  
VSENM  
-
Analog  
internal reference voltage.  
Signal ground for the internal circuitry except the internal  
reference voltage.  
Multi-function pin. Connect a resistor to a quiet ground to set  
Analog the switching frequency to 1 of 8 settings and sets the mode  
of operation to FCCM or DEM.  
32  
36  
AGND  
-
I
Ground  
TON/MODE  
Not  
28, 33, 34,  
35  
NC  
-
Not connected internally. They can be left floating on PCB.  
connected  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Absolute maximum ratings  
5 Absolute maximum ratings  
Absolute maximum ratings  
Description  
Min  
Max  
Unit  
Conditions  
PVin, Vin, En to PGND  
-0.3  
25  
V
Note 1  
PVin to SW and PHASE  
-0.3 V(dc) ,  
below -5 V for 5 ns  
-0.3  
25 V(dc),  
above 32 V for 2 ns  
V
VCC, VDRV to PGND  
BOOT to PGND  
6
V
V
Note 1  
Note 1  
-0.3 V(dc),  
below -0.3 V for 5 ns  
-0.3 (dc),  
29  
SW and PHASE to PGND  
BOOT to PHASE  
25 V(dc),  
above 32 V for 2 ns  
6 V(dc),  
V
V
Note 1  
below -5 V for 5 ns  
-0.3  
7 V for 5 ns  
ILIM, FB, PGood, TON/MODE,  
GATEL and SS to AGND  
PGND to AGND  
-0.3  
6
V
Note 1  
-0.3  
-0.3  
0.3  
0.3  
V
V
VSENM to AGND  
Storage Temperature Range  
Junction Temperature Range  
-55  
-40  
150  
150  
°C  
°C  
Note:  
1. PGND, VSENM, and AGND pin are connected together  
Attention:  
Stresses beyond these listed under ꢀAbsolute Maximum Ratingsꢁ may cause permanent  
damage to the device. These are stress ratings only and functional operation of the device at  
these or any other conditions beyond those indicated in the operational sections of the  
specifications are not implied.  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Thermal Characteristics  
6
Thermal Characteristics  
6.1  
Thermal Characteristics  
Description  
Symbol  
Values  
19 °C/W  
1.1 °C/W  
24 °C/W  
Test Conditions  
Note 2  
Junction to Ambient Thermal Resistance  
Junction to PCB Thermal Resistance  
Junction to Case Top Thermal Resistance  
θJA  
θJC-PCB  
θJC  
Note 3  
Note:  
2. Thermal resistance is measured with components mounted on a standard EVAL_3889_1Vout demo board in  
free air.  
3. Thermal resistance is based on the board temperature near the pin 22.  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Electrical specifications  
7
Electrical specifications  
7.1  
Recommended operating conditions  
Description  
Min  
2
Max  
17  
Unit  
V
Note  
Note 4, Note 5  
Note 5, Note 6 & 10  
Note 4, Note 7  
Note 8, Note 9  
Note 9  
PVin Voltage Range with External VCC  
PVin Voltage Range with Internal LDO  
VCC and VDRV Supply Voltage Range  
Output Voltage Range  
4.5  
4.3  
0.8  
17  
V
5.5  
6
V
V
Continuous Output Current Range  
Switching Frequency  
30  
A
600  
-40  
2000  
125  
kHz  
°C  
Note 10  
Operating Junction Temperature  
Note:  
4. Vin is shorted to VCC and use an external bias voltage.  
5. A common practice is to have 20% margin on the maximum SW node voltage in the design. For applications  
requiring PVin equal to or above 14 V, a small resistor in series with the Boot pin should be used to ensure the  
maximum SW node spike voltage does not exceed 20 V. Alternatively, a RC snubber can be used at the SW node  
to reduce the SW node spike.  
6. Vin is connected to PVin and the internal LDO is used. For single-rail applications with the internal LDO and PVin  
=Vin = 4.3 V-5.4 V, the internal LDO may enter dropout mode. OCP limits can be reduced due to the lower VCC  
voltage. Please refer to Section 12.7 for more detailed design guidelines.  
7. The IR3889 is designed to function with VCC down to 4.2 V, however, electrical specifications such as OCP limits  
may be degraded.  
8. The maximum output voltage is also limited by the minimum off-time. Please refer to Section 12.13 for details.  
Also note that OCP limit may be degraded when off-time is close to the minimum off-time.  
9. Refer to Section 9 for maximum output current rating at different ambient temperatures.  
10. The maximum LDO output current must be limited within 50 mA for operations requiring full operating  
temperature range of -40 °C TJ 125 °C. Figure 6 shows the maximum LDO output current capability over  
junction temperature. Thermal de-rating may be needed at an elevated ambient temperature to ensure the  
junction temperature within the recommended operating range.  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Electrical specifications  
7.2  
Electrical characteristics  
Note:  
Unless otherwise specified, the specifications apply over 4.5 V ≤ Vin = PVin ≤ ꢀ7 V, ꢁ °C < TJ < 125 °C.  
Typical values are specified at Ta = 25 °C.  
Parameter  
Symbol  
Conditions  
Min Typ  
Max  
Unit  
Power Stage  
Top Switch  
Rds(on)_Top  
Rds(on)_Bot  
VBoot Vsw= 5.0 V, IO = 30 A, Tj =25 °C  
VCC = 5.0 V, Io = 30 A, Tj =25 °C  
I(BOOT) = 25 mA  
2.4  
0.8  
280  
mΩ  
mV  
mV  
Bottom Switch  
Bootstrap Forward Voltage  
600  
300  
300  
En = 0 V  
SW float voltage  
VSW  
En = high, No Switching  
SW node falling edge, Io = 30 A,  
Internal LDO, Tj = 25 °C, Note 11  
10  
5
ns  
ns  
Dead Band Time  
Tdb  
SW node rising edge, Io = 30 A,  
Internal LDO, Tj = 25 °C, Note 11  
Supply Current  
Vin Supply Current (standby)  
Vin Supply Current (static)  
Iin(Standby)  
Iin(Static)  
En = Low, No Switching  
En=2 V, No Switching  
4
10  
4
µA  
2.3  
mA  
Soft Start  
SS/Latch = 0 kΩ, 4.53 kΩ,  
10.5 kΩ, 18.7 kΩ;  
0.4  
0.2  
0.1  
0.8  
0.4  
0.2  
1.12  
0.56  
0.28  
SS/Latch =1.5 kΩ, 5.76 kΩ,  
12.1 kΩ, 21.5 kΩ;  
Soft Start Ramp Rate  
SS rate  
mV/s  
SS/Latch = 2.49 kΩ, 7.32 kΩ,  
14 kΩ, 24.9 kΩ, Floating  
SS/Latch = 3.48 kΩ, 8.87 kΩ,  
ꢂꢃ.ꢀ kΩ, ꢀꢄ.ꢅ kΩ;  
0.05  
0.1  
0.145  
Feedback Voltage  
Feedback Voltage  
VFB  
V
0.8  
-0.5  
+0.5  
0°C < Tj < 85 °C  
Accuracy  
%
nA  
-40 °C < Tj < 125 °C, Note 12  
VFB=0.8 V, Tj=25 C  
-1  
1
VFB Input Current  
IVFB  
-150  
0
+150  
On-Time Timer Control  
Vin=12 V, Vo=1 V,  
151  
114  
91.5  
77  
TON= ꢆ kΩ or ꢂꢆ.ꢇ kΩ, Note 13  
Vin=12 V, Vo=1 V,  
TON= 1.5 kΩ or 12.1 kΩ, Note 13  
Ton  
On Time  
ns  
Vin=12 V, Vo=1 V,  
TON= 2.49 kΩ, or 14 kΩ, Note 13  
Vin=12 V, Vo=1 V,  
TON= 3.48 kΩ, or 16.2 kΩ, Note 13  
Final Datasheet  
12 of 50  
V2.7  
2022-4-4  
 
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Electrical specifications  
Parameter  
Symbol  
Conditions  
Min Typ  
Max  
Unit  
Vin=12 V, Vo=1 V,  
66.5  
TON= ꢈ.ꢇꢉ kΩ, or 18.7 kΩ, Note 13  
Vin=12 V, Vo=1 V,  
58.5  
52  
TON= 5.76 kΩ, or 21.5 kΩ, Note 13  
Vin=12 V, Vo=1 V,  
Ton  
On Time  
ns  
TON= 7.32 kΩ, or 24.9 kΩ, Note 13  
Vin=12V , Vo=1 V,  
47  
TON= 8.ꢄꢅkΩ, or ꢀꢄ.ꢅkΩ, Note 13  
Vin=12V, Vo=1.0V,  
114  
TON = Floating, Note 13  
Vin=12 V, Vo=0 V  
Ton (Min)  
Toff (Min)  
23  
32  
Minimum On-Time  
Minimum Off-Time  
VCC LDO Output  
ns  
ns  
270  
360  
Tj=25 C, VFB=0 V  
5.5 V Vin 17 V,  
when Icc =50 mA, Cload = 2.2 µF  
Output Voltage  
VCC  
4.7  
5.0  
90  
5.3  
V
VCC Dropout  
VCC_drop  
Ishort  
Vin = 4.3 V, Icc=50 mA, Cload=2.2 µF  
300  
mV  
mA  
Short Circuit Current  
5.5 V Vin 17 V  
Under Voltage Lockout  
VCC-Start Threshold  
VCC-Stop Threshold  
Enable-Start-Threshold  
Enable-Stop-Threshold  
Input Impedance  
VCC_UVLO_Start  
VCC_UVLO_Stop  
En_UVLO_Start  
En_UVLO_Stop  
REN  
VCC Rising Trip Level  
VCC Falling Trip Level  
ramping up  
3.8  
3.6  
4.0  
3.8  
1.2  
1
4.2  
4.0  
V
V
1.14  
0.9  
1.36  
1.06  
1500  
V
ramping down  
500  
1000  
k  
Over Current Limit  
Tj = 25 °C, int LDO, RILIM=24.9 kΩ  
Tj = 25 °C, int LDO, RILIM=21.5 kΩ  
Tj = 25 °C, int LDO, RILIM=16.2 kΩ  
Tj = 25 °C, int LDO, RILIM=ꢂꢀ.ꢂ kΩ  
33.9  
28.3  
22.6  
15.0  
39  
32.5  
26  
45.0  
37.4  
29.9  
23.0  
Current Limit Threshold  
(Valley current)  
Ioc  
A
19.5  
Over Voltage Protection  
FB Rising  
115  
110  
121  
115  
7
125  
120  
OVP Trip Threshold  
OVP_Vth  
% Vref  
FB Falling, OVP hysteresis  
OVP Protection Delay  
Hiccup Blanking Time  
OVP_Tdly  
µs  
Tblk_Hiccup  
Unlatched OVP  
FB Falling  
20  
ms  
Under Voltage Protection  
UVP Trip Threshold  
UVP_Vth  
UVP_Tdly  
65  
85  
70  
5
75  
% Vref  
µs  
UVP Protection Delay  
Hiccup Blanking Time  
Tblk_Hiccup  
20  
ms  
Power Good  
PGood Turn on Threshold  
VPG(upper)  
FB Rising  
13 of 50  
91  
95 % Vref  
Final Datasheet  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Electrical specifications  
Parameter  
Symbol  
VPG(lower)  
IPG  
Conditions  
FB Falling  
Min Typ  
Max  
90  
Unit  
% Vref  
mA  
PGood Turn off Threshold  
PGood Sink Current  
PGood Voltage Low  
80  
84  
PG = 0.5 V, En = 2 V  
2.5  
5
VPG(low)  
Vin = VCC =0 V, Rpull-up = 50 kto  
3.3 V  
0.3  
2.5  
2
0.5  
V
PGood Turn on Delay  
VPG(on)_Dly  
FB Rising, see VPG(upper)  
ms  
µs  
PGood Comparator Delay  
VPG(comp)_Dly  
VFB < VPG(lower) or  
VFB > VPG(upper)  
1
3.5  
1
PGood Open Drain Leakage  
Current  
PG = 3.3 V  
µA  
Thermal Shutdown  
Thermal Shutdown  
Hysteresis  
140  
20  
Note 11  
Note 11  
°C  
Note:  
11. Guaranteed by construction and not tested in production  
12. Cold temperature performance is guaranteed via correlation using statistical quality control. Not tested in  
production.  
13. The Ton is trimmed so that the target switching frequency is achieved at around 10A load current using  
EVAL_3889_1Vout demo board.  
Final Datasheet  
14 of 50  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Typical efficiency and power loss curves  
8
Typical efficiency and power loss curves  
8.1  
PVin = Vin = ꢃꢄ V, fsw = ꢅꢆꢆ kHz  
PVin = Vin = 12 V, VCC = Internal LDO, Io = 0 A-30 A, fsw= 600 kHz, Room Temperature, No Air Flow. Note that the  
efficiency and power loss curves include the losses of IR3889, the inductor losses, the losses of the input and  
output capacitors, and PCB trace losses. The table below shows the inductors used for each of the output  
voltages in the efficiency measurement.  
Table 1  
Inductors for PVin = Vin = 12 V, fsw = 600 kHz  
Vo (V)  
Lout (nH)  
150  
P/N  
Size (mm)  
12.4 x 8.3 x 8  
12.4 x 8.3 x 8  
10.8 x 8 x 8  
DCR (m)  
0.15  
HCB138380D-151 (Delta)  
HCB138380D-151 (Delta)  
FP1008R5-R220-R (Cooper)  
HCBD101195-351(Delta)  
HCBD101195-451(Delta)  
1.0  
1.2  
1.8  
3.3  
5
150  
0.15  
220  
0.17  
350  
0.35  
10.1 x 11.4 x 9.5  
10.1 x 11.4 x 9.5  
450  
0.35  
Final Datasheet  
15 of 50  
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30 A single-voltage synchronous Buck regulator  
Typical efficiency and power loss curves  
8.2  
PVin = Vin = ꢃꢄ V, fsw = ꢁꢆꢆ kHz  
PVin = Vin = 12 V, VCC = Internal LDO, Io = 0 A-30 A, fsw = 800 kHz, Room Temperature, No Air Flow. Note that the  
efficiency and power loss curves include the losses of IR3889, the inductor losses, the losses of the input and  
output capacitors, and PCB trace losses. The table below shows the inductors used for each of the output  
voltages in the efficiency measurement.  
Table 2  
Inductors for PVin = Vin =12 V, fsw = 800 kHz  
Vo (V)  
Lout (nH)  
150  
P/N  
Size (mm)  
12.4 x 8.3 x 8  
12.4 x 8.3 x 8  
12.4 x 8.3 x 8  
10.1 x 11.4 x 9.5  
DCR (m)  
0.15  
1.0  
1.2  
1.8  
3.3  
HCB138380D-151 (Delta)  
HCB138380D-151 (Delta)  
HCB138380D-151 (Delta)  
HCBD101195-351(Delta)  
150  
0.15  
150  
0.15  
350  
0.35  
Final Datasheet  
16 of 50  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Typical efficiency and power loss curves  
8.3  
PVin = Vin = ꢃꢄ V, fsw = ꢃꢆꢆꢆ kHz  
PVin = Vin = 12 V, VCC = Internal LDO, Io = 0 A-30 A, fsw = 1000 kHz, Room Temperature, No Air Flow. Note that  
the efficiency and power loss curves include the losses of IR3889, the inductor losses, the losses of the input  
and output capacitors, and PCB trace losses. The table below shows the inductors used for each of the output  
voltages in the efficiency measurement.  
Table 3  
Inductors for PVin = Vin = 12 V, fsw = 1000 kHz  
Vo (V)  
Lout (nH)  
100  
P/N  
Size (mm)  
6.4 x 9.5 x 10  
6.4 x 9.5 x 10  
6.4 x 9.5 x 10  
DCR (m)  
0.145  
1.0  
1.2  
1.8  
AH3740A-100K (ITG)  
AH3740A-100K (ITG)  
AH3740A-120K (ITG)  
100  
0.145  
120  
0.145  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Typical efficiency and power loss curves  
8.4  
PVin = Vin = VCC = ꢇ V, fsw = ꢅꢆꢆ kHz  
PVin = Vin = VCC = 5.0 V, Io = 0 A 30 A, fsw = 600 kHz, Room Temperature, No Air Flow. Note that the efficiency  
and power loss curves include the losses of IR3889, the inductor losses, the losses of the input and output  
capacitors and and PCB trace losses. The table below shows the inductors used for each of the output voltages  
in the efficiency measurement.  
Table 4  
Inductors for PVin = Vin = VCC= 5 V, fsw = 600 kHz  
Vo (V)  
Lout (nH)  
120  
P/N  
Size (mm)  
6.4 x 9.5 x 10  
6.4 x 9.5 x 10  
6.4 x 9.5 x 10  
6.4 x 9.5 x 10  
DCR (m)  
0.145  
AH3740A-120K (ITG)  
AH3740A-120K (ITG)  
AH3740A-150K (ITG)  
AH3740A-150K (ITG)  
1.0  
1.2  
1.8  
3.3  
120  
0.145  
150  
0.145  
150  
0.145  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Thermal De-rating curves  
9
Thermal De-rating curves  
Measurement is done on Evaluation board of EVAL_3889. PCB is a 6-layer board with 1.5 ounce Copper for top  
and bottom layer and 2 z Copper for the inner layers, FR4 material, size ꢉ.ꢆꢋxꢉ.75ꢋ.  
Figure 4 Thermal de-rating curves, PVin = 12 V, Vo = 1.0 V/3.3 V/5 V, Fsw = 800 kHz, VCC = Internal LDO  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
RDS(ON) of MOSFET Over Temperature  
10  
RDSꢈONꢉ of MOSFET Over Temperature  
Figure 5 RDS(on) of MOSFETs over Junction Temperature  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Typical operating characteristics (-ꢊꢆ C ≤ Tj ≤ +ꢃꢄꢇ Cꢉ  
11  
Typical operating characteristics ꢈ-ꢊꢆ °C ≤ Tj ≤ +ꢃꢄꢇ °Cꢉ  
Figure 6 Typical operating characteristics (set 1 of 3)  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Typical operating characteristics (-ꢊꢆ C ≤ Tj ≤ +ꢃꢄꢇ Cꢉ  
Figure 7 Typical operating characteristics (set 2 of 3)  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Typical operating characteristics (-ꢊꢆ C ≤ Tj ≤ +ꢃꢄꢇ Cꢉ  
Figure 8 Typical operating characteristics (set 3 of 3)  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Theory of operation  
12  
Theory of operation  
12.1  
Fast Constant On-Time Control  
The IR3889 features a proprietary Fast Constant On-Time (COT) Control, which can provide fast load transient  
response, good output regulation and minimize the design effort. Fast COT control compares the output voltage,  
Vo, to a floor voltage combined with an internal ramp signal. When Vo drops below that signal, a PWM signal is  
initiated to turn on the high-side FET for a fixed on-time. The floor voltage is generated from an internal  
compensated error amplifier, which compares the Vo with a reference voltage. Compared to the traditional COT  
control, Fast COT control significantly improves the Vo regulation.  
12.2  
Enable  
En pin controls the on/off of the IR3889. An internal Under Voltage Lock-Out (UVLO) circuit monitors the En  
voltage. When the En voltage is above an internal threshold, the internal LDO starts to ramp up. When the  
VCC/LDO voltage rises above the VCC_UVLO_Start threshold, the soft-start sequence starts. The En pin can be  
configured in three ways, as shown in Figure 9. With configuration 2, the Enable signal is derived from the PVin  
voltage by a set of resistive divider, REN1 and REN2. By selecting different divider ratios, users can program a  
UVLO threshold voltage for the bus voltage. This is a very desirable feature because it prevents the IR3889 from  
operating until PVin is higher than a desired voltage level. For some space constrained designs, the En pin can be  
directly connected to PVin without using the external resistor dividers, as shown in Configuration 3. The En pin  
should not be left floating. A pull down resistor in the range of tens of kilohms is recommended. Figure 10  
illustrates the corresponding start-up sequences with three En configurations.  
PVin  
PVin  
PVin  
Vin  
PVin  
REN1  
Vcc  
PVin  
PVin  
Vin  
Vin  
En  
Vcc  
Vcc  
IR3889  
En  
En  
IR3889  
IR3889  
REN2  
ꢂꢃꢄ  
En = an external logic signal  
Configuration 1  
En = ꢁ  
× ꢇꢈꢉ  
ꢂꢃꢄ  
PVin = Vin = En  
Configuration 3  
+ꢁ  
ꢂꢃꢅ  
Configuration 2  
Figure 9 Enable Configurations  
Final Datasheet  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Theory of operation  
Pvin= Vin=12V  
PVin=Vin=En=12V  
Pvin = Vin = 12V  
Vcc_ UVLO  
Vcc  
Vcc  
Vcc  
Vcc_UVLO  
En Threshold  
0V  
Vcc_ UVLO  
0V  
0V  
0V  
0V  
En = REN2/(REN1+REN2)*PVin  
Fb  
0V  
En>1.2V  
En Threshold  
Fb  
0V  
Fb  
0V  
Pgood Turn-on  
threshold  
Pgood Turn-on  
threshold  
Pgood Turn-on  
threshold  
2.5ms  
2.5ms  
2.5ms  
0V  
0V  
0V  
0V  
0V  
0V  
PGood  
PGood  
PGood  
Pgood stays at logic low  
Pgood stays at logic low  
Pgood stays at logic low  
ꢂꢃꢄ  
En = an external logic signal  
Configuration 1  
En = ꢁ  
× ꢇꢈꢉ  
ꢂꢃꢄ  
PVin = Vin = En  
Configuration 3  
+ꢁ  
ꢂꢃꢅ  
Configuration 2  
Figure 10 Start-up sequence  
12.3  
FCCM and DEM Operation  
The IR3889 offers two operation modes: Forced Continuous Conduction (FCCM) and Diode Emulation Mode  
(DEM). With FCCM, the IR3889 always operates as a synchronous buck converter with a pseudo constant  
switching frequency and therefore achieves small output voltage ripples. In DEM, the synchronous FET is turned  
off when the inductor current is close to zero, which reduces the switching frequency and improves the efficiency  
at light load. At heavy load, both FCCM and DEM operate in the same way. The operation mode can be selected  
with TON/MODE pin, as shown in Table 5. It should be noted that the selection of the operation mode cannot be  
changed on the fly. To load a new TON/MODE configuration, En or VCC voltage needs to be cycled.  
12.4  
Pseudo Constant Switching Frequency  
The IR3889 offers eight programmable switching frequencies, fsw, from 600 kHz to 2 MHz, by connecting an  
external resistor from TON/MODE pin to a quiet ground (AGND or PGND). Based on the selected fsw, the IR3889  
generates the corresponding on-time of the Control FET for a given PVin and Vo, as shown by the formula below.  
ꢍ  
ꢋꢉ  
=
×
ꢆꢌ  
ꢐꢑ  
ꢈꢉ  
Where fsw is the desired switching frequency. During the operation, the IR3889 monitors PVin and Vo, and can  
automatically adjust the on-time to maintain the pre-selected fsw. With the increase of the load, the switching  
frequency can increase to compensate for the power losses. Therefore, the IR3889 has a pseudo constant  
switching frequency.  
Table 5 lists the resistors for TON/MODE pin. In this table, E96 resistors with ±1% tolerance are used. If E12  
resistor values are preferred, please refer to the Section 12.15. To load a new TON/MODE configuration, En or  
VCC voltage needs to be cycled.  
Final Datasheet  
25 of 50  
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IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Theory of operation  
Table 5 Configuration Resistors for TON/MODE Pin  
TON/MODE Resistor (kΩꢉ  
Freq (kHz)  
Mode  
±1% Tolerance  
0
1.5  
600  
800  
2.49  
1000  
1200  
1400  
1600  
1800  
2000  
600  
3.48  
FCCM  
4.53  
5.76  
7.32  
8.87  
10.5  
12.1  
800  
14  
1000  
1200  
1400  
1600  
1800  
2000  
800  
16.2  
DEM  
18.7  
21.5  
24.9  
28.7  
Ton = Floating  
FCCM  
12.5  
Soft-start  
The IR3889 has an internal digital soft-start to control the output voltage rise and to limit the current surge at the  
start-up. To ensure a correct start-up, the soft-start sequence initiates when the En and VCC voltages rise above  
their respective thresholds. The internal soft-start signal linearly rises from 0 V to 0.8 V in a defined time duration.  
The soft-start time does not change with the output voltage. During the soft-start, the IR3889 operates in DEM  
until 1ms after the output voltage ramps above the PGood turn-on threshold. The IR3889 has four soft-start time  
options selected by placing a resistor from SS/Latch pin to the ground. Table 6 lists the resistor values and its  
corresponding soft-start time. In this table, E96 resistors with ±1% tolerance are used. If E12 resistor values are  
preferred, please refer to the Section 12.15. For each soft-start time, there are two resistor options available.  
Please note that SS/Latch pin is a multi-function pin, which is also used to select different responses for Over  
Voltage Protection (OVP). Please note that to load a new SS/Latch selection, En or VCC voltage needs to be  
cycled.  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Theory of operation  
Table 6 Configuration Resistor for SS/Latch Pin  
SS/Latch Resistor ꢈkΩꢉ  
Soft-start Time  
(ms)  
OVP  
±1% Tolerance  
0
1
2
4
8
1
2
4
4.53  
1.5  
5.76  
Latch  
2.49  
7.32  
3.48  
8.87  
10.5  
18.7  
12.1  
21.5  
No Latch  
Latch  
14  
24.9  
16.2  
8
4
28.7  
SS/Latch = Floating  
12.6  
Pre-bias Start-up  
The IR3889 is able to start up into a pre-charged output without causing oscillations and disturbances of the  
output voltage. When IR3889 starts up with a pre-biased output voltage, both control FET and Synch FET are  
kept off till the internal soft-start signal exceeds the FB voltage.  
12.7  
Internal Low - Dropout ꢈLDOꢉ Regulator  
The IR3889 has an integrated low-dropout LDO regulator, providing the bias voltage for the internal circuitry. To  
minimize the standby current, the internal LDO is disabled when the En voltage is pulled low. Vin pin is the input  
of the LDO. When using the internal LDO for a single rail operation, Vin pin should be connected to PVin pin. To  
save the power losses on the LDO, an external bias voltage can be used by connecting Vin pin to the VCC/LDO  
pin. VDRV provides the bias voltage for the internal driver circuitry and should be shorted to VCC/LDO on the PCB.  
Figure 11 illustrates the configuration of VCC/LDO, VDRV and Vin pin.  
Ext Vcc  
PVin  
PVin  
4.7uF  
Vin  
VCC  
Vin  
VCC  
PVin  
PVin  
VDRV  
VDRV  
IR3889  
2.2uF ~10uF  
10uF  
IR3889  
PGND  
PGND  
Single rail operation with the internal LDO Use an external VCC  
Figure 11 Configuration of Using the internal LDO or an external VCC.  
Final Datasheet 27 of 50  
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30 A single-voltage synchronous Buck regulator  
Theory of operation  
Section 7.1 specified the recommended operating voltage range of Vin and VCC under different configurations.  
Following design guidelines are recommended when configuring the VCC/LDO.  
Place a bypass capacitor to minimize the disturbance on the VCC and VDRV pin. For a single rail operation  
using the internal LDO, a 4.7 µF low ESR ceramic capacitor must be used between Vin pin and PGND and a 2.2  
µF~10 µF low ESR ceramic capacitor is required to be placed close to the VCC/LDO and VDRV pin with reference  
to PGND. 10 µF MLCC is recommended for VCC bypass capacitor when Vin is below 5.5 V. When using an  
external VCC bias voltage, a 10 µF ceramic capacitor can be shared with Vin, VCC/LDO and VDRV pin.  
When using the internal LDO with 5.5 V Vin 17 V, it is recommended to check the required VCC bias current  
for the operation above 1.6 MHz, to ensure that it does not exceed the LDO output current capability as shown  
in Figure 6. With the increase of fsw, the resulting ICC is also increased mainly due to the increase of the gate  
charge that is proportional to fsw. In Figure 6, the typical ICC at PVin = Vin = 12 V and fsw = 800 kHz has been  
provided, which can be used to estimate the ICC at other fsw.  
For applications using the internal LDO with 4.3 V Vin ꢊ ꢇ.ꢈ V, the LDO can be in the dropout mode. It is  
important to ensure that the LDO voltage does not fall below the VCC UVLO threshold voltage. At Vin = 4.3 V,  
ICC must not exceed 50 mA under all operating conditions such as during a step-up load transient, in which the  
control loop may require the increase of fsw. OCP limits can be reduced due to the lower VCC voltage.  
12.8  
Over Current Protection ꢈOCPꢉ  
The IR3889 offers cycle-by-cycle OCP response with four selectable current limits, which is set by the resistance  
at ILIM pin. The selected OCP limit bank is loaded to the IC during the power up and cannot be changed on the  
fly. To change the OCP limit, users must cycle En signal or VCC voltage. Cycle-by-cycle OCP response allows the  
IR3889 to fulfill a brief high current demand, such as a high inrush current during the start-up. The detailed  
operation is explained as follows.  
The OCP is activated when En voltage is above its threshold. The OCP circuitry monitors the current of the  
Synchronous MOSFET through its Rds(on). When a new PWM pulse is requested by the control loop, if the current  
of Synchronous MOSFET exceeds the selected OCP limit, the IR3889 skips the PWM pulse and extends the on-  
time of Synchronous MOSFET till the current drops below the OCP limit. The OCP operation is also illustrated in  
Figure 12. As can be seen, during OCP events, the valley of the inductor current is regulated around the OCP  
limit. But during the first switching cycle when the OCP is tripped, the valley of the inductor current can drop  
slightly below the OCP limit. It should be noted that OCP events do not pull the PGood signal low unless the Vo  
drops below the PGood turn-off threshold. If the OCP event persists, the output voltage can eventually drop  
below the Under Voltage Protection (UVP) threshold and trigger UVP. Then the IR3889 enters a hiccup mode.  
The OCP limits are thermally compensated. Please refer to the typical performance of OCP limits in Figure 7and  
Figure 8. The OCP limits specified in the Section 7.2 refer to the valley of the inductor current when OCP is  
tripped. Therefore, the corresponding output DC current can be calculated as follows:  
∆ꢜꢘ  
ꢋꢓꢔ_ꢕꢖꢗ = ꢒꢘꢙꢚ  
Where: Iout_OCP = Output DC current when OCP is tripped. ILIM = OCP limit specified in the Section 7.2, which is the  
valley of inductor current. ΔiL = Peak-peak inductor ripple current.  
To avoid the inductor saturation during OCP events, the following criterion is recommended for the inductor  
saturation current rating.  
ꢐꢞꢔ ꢟ ꢒꢘꢙꢚ_ꢠꢞꢡ ꢛ ∆ꢜꢘ  
Where: Isat is the inductor saturation current and ILIM_max is the maximum spec of the OCP limit.  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Theory of operation  
OCP Tripped  
Current  
Limit  
UVP Hiccup  
Blanking  
time  
Inductor  
Pulse  
Current  
skipped  
HDrv  
LDrv  
PGood  
UVP  
Threshold  
Vo  
PGood Turn-off  
Threshold  
Figure 12 Cycle-by-cycle OCP response  
12.9  
Under Voltage Protection ꢈUVPꢉ  
Under Voltage Protection (UVP) provides additional protection during OCP fault or other faults. UVP is activated  
when the soft-start voltage rises above 130 mV. UVP circuitry monitors the FB voltage. When it is below the UVP  
threshold for 5 µs (typical), an under voltage trip signal asserts and both Control MOSFET and Synchronous  
MOSFET are turned off. The IR3889 enters a hiccup mode with a blanking time of 20 ms, during which Control  
MOSFET and Synchronous MOSFET remain off. After the completion of blanking time, the IR3889 attempts to  
recover to the nominal output voltage with a soft-start, as shown in Figure 12. The IR3889 will repeat hiccup  
mode and attempt to recover until UVP condition is removed.  
12.10  
Over Voltage Protection ꢈOVPꢉ  
Over Voltage Protection (OVP) is achieved by comparing the FB voltage to an OVP threshold voltage. When the  
FB voltage exceeds the OVP threshold, an over voltage trip signal asserts after 7 µs (typical) delay. Control  
MOSFET is latched off immediately and PGood flags low. Synchronous MOSFET remains on to discharge the  
output capacitor. When FB voltage drops below around 115% of the reference voltage, Synchronous MOSFET  
turns off to prevent the complete depletion of the output capacitors. Figure 13 illustrates the OVP operation.  
The OVP comparator becomes active when the En signal is above the start threshold.  
With SS/Latch pin, two OVP responses can be selected: Latch or No Latch, as shown in Table 6. With a latched  
OVP response, Control FET remains latched off until either VCC voltage or En signal is cycled. With an unlatched  
OVP response, the IR3889 enters a hiccup mode. Control FET remains off for a blanking time of 20ms. After hiccup  
blanking time expires, the IR3889 will try to restart with a soft-start. The IR3889 can stay in the hiccup mode  
infinitely if over voltage fault persists.  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Theory of operation  
HDrv  
LDrv  
121%Vref  
115%Vref  
Vref  
OVP  
91%Vref  
91%Vref  
84%Vref  
VFB  
PGood  
Pgood turn-on  
delay =2.5ms  
Pgood turn-on  
delay =2.5ms  
OVP delay =7us  
Figure 13 Over voltage protection response and PGood behavior.  
12.11  
Over Temperature Protection ꢈOTPꢉ  
Temperature of the controller is monitored internally. When the temperature exceeds the over temperature  
threshold, OTP circuitry turns off both Control and Synchronous MOSFETs and resets the internal soft start.  
Automatic restart is initiated when the sensed temperature drops back into the operating range. The thermal  
shutdown threshold has a hysteresis of 20 °C.  
12.12  
Power Good ꢈPGoodꢉ Output  
The PGood pin is the open drain of an internal NFET, and needs to be externally pulled high through a pull-up  
resistor. PGood signal is high when three criteria are satisfied.  
1. En signal and VCC voltage are above their respective thresholds.  
2. No over voltage and over temperature faults occur.  
3. Vo is within the regulation.  
In order to detect if Vo is in regulation, PGood comparator continuously monitors the FB voltage. When FB voltage  
ramps up above the upper threshold, PGood signal is pulled high after 2.5 ms. When FB voltage drops below the  
lower threshold, PGood signal is pulled low immediately. Figure 13 illustrates the PGood response.  
During the start-up with a pre-biased voltage, PGood signal is held low before the first PWM is generated and is  
then pulled high with 2.5 ms delay after FB voltage rises above the PGood threshold. IR3889 also integrates an  
additional PFET in parallel to the PGood NFET, as shown in Figure 2. This PFET allows PGood signal to stay at  
logic low when the VCC voltage is not present, and PGood pin is pulled up by an external bias voltage. Please  
refer to Figure 10. Since PGood PFET has relatively higher on resistance, a 50 kΩ pull-up resistor is needed for a  
PGood bias voltage of 3.3 V to maintain the PGood signal at logic low when PGood PFET is on.  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Theory of operation  
12.13  
Minimum On - Time and Minimum Off - Time  
The minimum on-time refers to the shortest time for Control MOSFET to be reliably turned on. The minimum off-  
time refers to the minimum time duration in which Synchronous FET stays on before a new PWM pulse is  
generated. The minimum off-time is needed for IR3889 to charge the bootstrap capacitor, and to sense the  
current of the Synchronous MOSFET for OCP.  
For applications requiring a small duty cycle, it is important that the selected switching frequency results in an  
on-time larger than the maximum spec of the minimum on-time in the Section 7.2. Otherwise the resulting  
switching frequency may be lower than the desired target. Following formula could be used to check for the  
minimum on-time requirement.  
ꢍ  
> max ꢣꢤꢥꢦ ꢧꢏ ꢋꢉ ꢩiꢪ  
ꢢꢏ × ꢆꢌ  
ꢐꢑ  
ꢈꢉ  
Where fsw is the desired switching frequency. k is the variation of the switching frequency. As a rule of thumb,  
select k = 1.25 to ensure the design margin.  
For applications requiring a high duty cycle, it is important to make sure a proper switching frequency is selected  
so that the resulting off-time is longer than the maximum spec of the minimum off-time in the Section 7.2, which  
can be calculated as shown below.  
ꢆꢌ − ꢍ  
ꢈꢉ  
> max ꢣꢤꢥꢦ ꢧꢏ ꢋꢬꢬ ꢩiꢪ  
ꢢꢏ × ꢆꢌ  
ꢐꢑ  
ꢈꢉ  
Where fsw is the desired switching frequency. k is the variation of the switching frequency. As a rule of thumb,  
select k = 1.25 to ensure the design margin.  
The resulting maximum duty cycle is therefore determined by the selected on-time and minimum off-time.  
ꢋꢉ  
ꢠꢞꢡ  
=
ꢋꢉ  
ꢋꢬꢬꢨꢩiꢪꢫ  
12.14  
Selection of Feedforward Capacitor and Feedback Resistors  
Output voltage can be programmed with an external voltage divider. The FB voltage is compared to an internal  
reference voltage of 0.8 V. The divider ratio is set to provide 0.8 V at the FB pin when the output is at its desired  
value. The calculation of the feedback resistor divider is shown below.  
ꢱꢲꢳ  
ꢌ = ꢌ × ꢨꢎ ꢛ  
ꢮꢯꢬ  
ꢱꢲꢴ  
Where RFB1 and RFB2 are the top and bottom feedback resistors.  
A small MLCC capacitor, Cff, is preferred in parallel with the top feedback resistor, RFB1, to provide extra phase  
boost and to improve the transient load response, as shown in Figure 14. Following formula can be used to help  
select Cff and RFB1. The value of Cff is recommended to be 100 pF or higher to minimize the impact of circuit  
parasitic capacitance. Table 7 lists the suggested m for some common outputs. Cff and RFB1 may be further  
optimized based on the transient load tests. Where Lo and Co are the output LC filter of the buck regulator.  
ꢶ ꢵ  
ꢱꢲꢳꢬꢬ  
=
ꢷ × ꢸ.ꢹ  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Theory of operation  
Vo  
RFB1 Cff  
RFB2  
FB  
Figure 14 Configuration of feedforward capacitor, Cff.  
Table 7 Selection of m  
Vo  
m
0.4  
0.6  
0.8  
ꢉ V ꢊ Vo ꢊ ꢇ V  
1.2 V < Vo < 3 V  
Vo ꢊ ꢂ.ꢀ V  
12.15  
Resistors for Configuration Pins  
To properly configure SS/LATCH pin, MODE/TON pin and ILIM pin, E96 resistors with ±1% tolerance must be  
used per Table 5, Table 6 and Section 7.2. If E12 resistor values are preferred, the E96 resistors can be replaced  
with two or three E12 resistors in series, as shown in Table 8. Note that the tolerance of E12 resistors must be  
±0.1%.  
Table 8 Replacement of E96 configuration resistors with E12 resistors in series  
E96 ±1%  
R ꢌkΩꢁ  
4.53  
1.50  
5.76  
2.49  
7.32  
3.45  
8.87  
10.5  
12.1  
21.5  
14  
E12 ±0.1% (R = RS1 + RS2 or RS1 + RS2 + RS3)  
RS1 ꢌkΩꢁ  
RS2 ꢌkΩꢁ  
1.8  
RS3 ꢌkΩꢁ  
2.7  
1.5  
5.6  
1.8  
6.8  
3.3  
8.2  
10  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
0.18  
0.18  
0
0.15  
0.68  
0.56  
0.15  
0.68  
0.47  
0.1  
12  
18  
3.3  
10  
3.9  
24.9  
16.2  
28.7  
21.5  
24.9  
22  
2.7  
15  
1.2  
27  
1.8  
18  
3.3  
22  
2.7  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Design example  
13  
Design example  
In this section, an example is used to explain how to design a buck regulator with the IR3889. The application  
circuit is shown in Figure 15. The design specifications are given below.  
PVin = 12 V (±10%)  
Vo = 1.0 V  
Io = 30 A  
Vo ripple voltage = ±1% of Vo  
Load transient response = ± 3% of Vo with a step load current = 9 A and slew rate = 30 A/µs  
13.1  
Enabling the IRꢀꢁꢁꢂ  
The IR3889 has a precise En threshold voltage, which can be used to implement a UVLO of the input bus voltage  
by connecting the En pin to PVin with a resistor divider, as shown in Configuration 2 of Figure 9. The En resistor  
divider, REN1 and REN2, can be calculated as follows.  
ꢺꢻꢴ  
ꢆꢌ  
×
ꢺꢻꢨꢩꢼꢽꢫ  
ꢈꢉꢨꢩiꢪꢫ  
ꢺꢻꢳ ꢛ ꢰꢺꢻꢴ  
ꢺꢻꢨꢩꢼꢽꢫ  
ꢈꢉꢨꢩiꢪꢫ ꢺꢻꢨꢩꢼꢽꢫ  
ꢺꢻꢴ ꢟ ꢰꢺꢻꢳ  
×
Where VEN(max) is the maximum spec of the En-start-threshold as defined in Section 7.2. For PVin(min) =10.8 V,  
select REN1=49.9 kand REN2=7.5 k.  
13.2  
Programming the Switching Frequency and Operation Mode  
The IR3889 has very good efficiency performance and is suitable for high switching frequency operation. In this  
case, 800 kHz is selected to achieve a good compromise between the efficiency, passive component size and  
dynamic response. In addition, FCCM operation is selected to ensure a small output ripple voltage over the entire  
load range. To select ꢄꢆꢆ kHz and FCCM operation, the TON/MODE pin can be left floating or connect a ꢂ.ꢇ kΩ  
resistor to a quiet ground (AGND or PGND) per Table 5.  
13.3  
Selecting Input Capacitors  
Without input capacitors, the pulse current of Control MOSFET is directly from the input supply power. Due to  
the impedance on the cable, the pulse current can cause disturbance on the input voltage and potential EMI  
issues. The input capacitors filter the pulse current, resulting in almost constant current from the input supply.  
The input capacitors should be selected to tolerate the input pulse current, and to reduce the input voltage  
ripple. The RMS value of the input ripple current can be expressed by:  
ꢁꢚꢾ = ꢒ × ꢭ × ꢨꢎ − ꢭꢫ  
ꢭ =  
ꢆꢌ  
ꢈꢉ  
Where IRMS is the RMS value of the input capacitor current. Io is the output current and D is the Duty Cycle. For Io  
= 30A and D(max) = 0.09, the resulting RMS current flowing into the input capacitor is Irms = 8.7 A.  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Design example  
To meet the requirement of the input ripple voltage, the minimum input capacitance can be calculated as  
follows.  
× ꢨꢎ − ꢭꢫ × ꢭ  
ꢈꢉꢨꢩiꢪꢫ  
>
ꢏ × ꢨ∆ꢆꢌ − ꢿꣀꢰ × ꢒ× ꢎ − ꢭ ꢫ  
ꢐꢑ  
ꢈꢉ  
Where ∆PVin is the maximum allowable peak-to-peak input ripple voltage, and ESR is the equivalent series  
resistor of the input capacitors. Ceramic capacitors are recommended due to low ESR, ESL and high RMS current  
capability. For Io = 30 A, fsw = ꢄꢆꢆ kHz, ESR = ꢉ mΩ, and ∆PVin = 240 mV, Cin(min) > 18 µF. To account for the de-  
rating of ceramic capacitors under a bias voltage, 10 x 22 µF/0805/25V MLCC are used for the input capacitors. In  
addition, a bulk capacitor is recommended if the input supply is not located close to the voltage regulator.  
13.4  
Inductor Selection  
The inductor is selected based on output power, operating frequency and efficiency requirements. A low inductor  
value results in a large ripple current, lower efficiency and high output noise, but helps with size reduction and  
transient load response. Generally, the desired peak-to-peak ripple current in the inductor ꢌ∆iꢁ is found between  
20% and 50% of the output current.  
The inductor saturation current must be higher than the maximum spec of the OCP limit plus the peak-to-peak  
inductor ripple current. For some core material, inductor saturation current may decrease as the increase of  
temperature. So it is important to check the inductor saturation current at the maximum operating temperature.  
The inductor value for the desired operating ripple current can be determined using the following relation:  
ꢠꢈꢉ  
ꢶ = ꢨꢆꢈꢉꢨꢩꢼꢽꢫ − ꢌ ꢫ ×  
∆ꢜꢘꢨꢩꢼꢽꢫ × ꣁ  
ꢐꢑ  
ꢠꢈꢉ  
=
ꢆꢌ  
ꢈꢉꢨꢩꢼꢽꢫ  
ꢐꢞꢔ ꢟ ꣂꢵꢠꢞꢡ ꢛ ∆ꢜꢘꢨꢩꢼꢽꢫ  
Where: PVin(max) = Maximum input voltage; ∆iLmax = Maximum peak-to-peak inductor ripple current; OCPmax  
=
maximum spec of the OCP limit as defined in Section 7.2; and Isat = inductor saturation current. In this case,  
select inductor L =150 nH to achieve ∆iLmax = 25% of Iomax. The Isat should be no less than 53 A.  
13.5  
Output Capacitor Selection  
The output capacitor selection is mainly determined by the output voltage ripple and transient requirements.  
To satisfy the Vo ripple requirement, Co should satisfy the following criterion.  
∆ꢜꢘꢠꢞꢡ  
>  
8 × ∆ꢌ × ꢏ  
ꢋꢮ  
ꢐꢑ  
Where ∆Vor is the desired peak-to-peak output ripple voltage. For ∆iLmax= 7.5 A, ∆Vor =20 mV, fsw = 800 kHz, Co  
must be larger than 59 µF. The ESR and ESL of the output capacitors, as well as the parasitic resistance or  
inductance due to PCB layout, can also contribute to the output voltage ripple. It is suggested to use Multi-  
Layer Ceramic Capacitor (MLCC) for their low ESR, ESL and small size.  
To meet the transient response requirements, the output capacitors should also meet the following criterion.  
ꢶ × ∆ꢒꢨꢩꢼꢽꢫ  
>  
ꢝ × ∆ꢌ × ꢌ  
ꢋꢘ  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Design example  
Where ∆VOL is the allowable Vo deviation during the load transient. ∆Io(max) is the maximum step load current.  
Please note that the impact of ESL, ESR, control loop response, transient load slew rate, and PWM latency is not  
considered in the calculation shown above. Extra capacitance is usually needed to meet the transient  
requirements. As a rule of thumb, we can triple the Co that is calculated above as a starting point, and then  
optimize the design based on the bench measurement. In this case, to meet the transient load requirement (i.e.  
∆VOL= 30 mV, ∆Io(max) = 9 A), select Co = ~600 µF. For more accurate estimation of Co, simulation tool should be  
used to aid the design.  
13.6  
Output Voltage Programming  
Output voltage can be programmed with an external voltage divider. The FB voltage is compared to an internal  
reference voltage of 0.8 V. The divider ratio is set to provide 0.8 V at the FB pin when the output is at its desired  
value. The calculation of the feedback resistor divider is shown below.  
ꢱꢲꢳ  
ꢌ = ꢌ × ꢨꢎ ꢛ  
ꢮꢯꢬ  
ꢱꢲꢴ  
Where RFB1 and RFB2 are the top and bottom feedback resistors. Select RFB1 = ꢂꢃ.ꢀ kΩ and RFB2 = ꢃꢈ.ꢍ kΩ, to achieve  
Vo = 1 V.  
13.7  
Feedforward Capacitor  
A small MLCC capacitor, Cff, can be placed in parallel with the top feedback resistor, RFB1, to improve the transient  
response. Based on Section 12.14, Cff can be selected using the following formula.  
ꢶ ꢵ  
ꢱꢲꢳꢬꢬ  
=
ꢸ.ꢹ × ꣃ.8  
With Lo = 150 nH, Co = 600 µF and RFB1 = ꢂꢃ.ꢀ kΩ, Cff = ~125 pF. Cff can be further optimized on the bench test based  
on bode plot measurement and transient load response.  
13.8  
Bootstrap Capacitor  
For most applications, a 0.1 µF ceramic capacitor is recommended for bootstrap capacitor placed between  
PHASE and BOOT Pin. For applications requiring PVin equal to or above 14 V, a small resistor of ꢂ~ꢀ Ω should be  
used in series with the BOOT pin to ensure the maximum SW node spike voltage does not exceed 20 V.  
13.9  
Vin, VCC/LDO and VDRV bypass Capacitor  
Please see the recommendation in Section 12.7. A 10 µF MLCC is selected for VCC/LDO and VDRV bypass  
capacitor and a 4.7 µF MLCC is selected for Vin bypass capacitor.  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Application Information  
14  
Application Information  
14.1  
Application Diagram  
Cin  
10 x 22uF  
CinHF  
4.7uF  
Vin = 12V 10%  
+
Optional  
REN1  
REN2  
49.9k ꢀ  
7.5k ꢀ  
Cvin  
4.7uF  
RBoot  
0 ꢀ  
PVin  
Vin  
EN  
Boot  
Phase  
SW  
CBoot  
0.1uF  
VCC/LDO  
VDRV  
Vo=1V  
RPG  
49.9k ꢀ  
Cvcc  
10uF  
L
150nH  
PGood  
+
CoHF  
0.1uF  
Co1  
1x470uF  
Co2  
9x47uF  
NC  
PGood  
IR3889  
GATEL  
SS/Latch  
RSS  
1.5k ꢀ  
Cff  
220pF  
Fb  
Ton/Mode  
ILIM  
VSENM  
RTon  
1.5k ꢀ  
AGnd  
PGnd NC NC  
NC  
RFB1  
16.2k ꢀ  
RFB2  
64.9k ꢀ  
RLIM  
24.9k ꢀ  
Figure 15 Application diagram of IR3889. PVin = 12 V, Vo = 1V, Io = 30 A, fsw = 800 kHz.  
14.2  
Typical Operating Waveforms  
PVin = Vin = 12.0 V, Vo = 1 V, Io = 0 30 A, fsw = 800 kHz, Room Temperature, no airflow  
Figure 16  
Start up at 30 A Load, (Ch1: PVin, Ch2: Vo, Ch3:PGood ,Ch4:En)  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Application Information  
Figure 17  
Pre-bias Start up at 0 A Load, (Ch1: PVin, Ch2: Vo, Ch3: PGood, Ch4: En)  
Figure 18  
Vo ripple at 30 A Load, fsw = 800 kHz, (Ch1: Vo)  
Figure 19  
SW node, 30 A load, fsw = 800 kHz  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Application Information  
Figure 20  
SW node (in DEM), 3.5 A load  
Figure 21  
Short circuit and UVP (Hiccup), (Ch2: Vo, Ch3:PGood)  
Figure 22  
Transient response at 9 A step load current @ 30 A/µs slew rate: Io= 16 A 25 A, (Ch1: Vo,  
Ch4: Io), pk-pk: 60.8 mV, fsw = 800 kHz  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Layout Recommendations  
15  
Layout Recommendations  
PCB layout is very important when designing high frequency switching converters. Layout will affect noise pickup  
and can cause a good design to perform with less than expected results. Following design guidelines are  
recommended to achieve the best performance.  
Bypass capacitors, including input/output capacitors, Vin, VCC and VDRV bypass capacitors, should be placed  
near the corresponding pins as close as possible.  
Place bypass capacitors from IR3889 power input (Drain of Control MOSFET) to PGND (Source of Synchronous  
MOSFET) to reduce noise and ringing in the system. The output capacitors should be terminated to a ground  
plane that is away from the input PGND to mitigate the switching spikes on the Vo. The bypass capacitor shared  
by VCC and VDRV should be terminated to PGND.  
Place a boot strap capacitor near the IR3889 BOOT and PHASE pin as close as possible to minimize the loop  
inductance.  
SW node copper should only be routed on the top layer to minimize the impact of switching noises  
Connect AGND pin to the PGND pad through a single point connection. On the IR3889 demo board, AGND pin  
is connected to the exposed PGND pad with a copper trace.  
Via holes can be placed on PVin and PGND pads to aid thermal dissipation.  
Wide copper polygons are desired for PVin and PGND connections in favor of power losses reduction and  
thermal dissipation. Sufficient via holes should be used to connect power traces between different layers.  
Single-ended Vo sensing is often used for local sensing. To implement this configuration, following design  
guidelines should be followed, as illustrated in Figure 23.  
o
The output voltage can be sensed from a high-frequency bypass capacitor of 0.1 µF or higher,  
through a 15 mil PCB trace.  
o
o
Keep the Vo sense line away from any noise sources and shield the sense line with ground planes.  
The sense trace is connected to a feedback resistor divider with the lower resistor terminated at  
VSENM pin.  
o
Short VSENM pin and AGND pin with a short trace.  
If it is required to sense the output voltage at a remote location, pseudo remoting sensing can be implemented  
as follows. The configuration is also shown in Figure 24.  
o
A pair of PCB traces with at least 15 mil trace width, running close to each other and away from  
any noise sources such as inductor and SW nodes, should be used to implement Kelvin sensing of  
the voltage across a high bypass capacitor of 0.1 µF or higher.  
o
o
The ground connection of the remote sensing signal must be terminated at VSENM pin.  
The Vo connection of the remote sensing signal must be connected to the feedback resistor divider  
with the lower feedback resistor terminated at VSENM pin.  
o
o
Shield the pair of remote sensing lines with ground planes above and below.  
Do NOT connect VSENM pin and AGND pin in this configuration  
The En pin and configuration pins including SS/LATCH, TON/MODE, and ILIM should be terminated to a quiet  
ground. On the IR3889 standard demo board, they are terminated to the PGND copper plane away from the  
power current flow. Alternatively, they can be terminated to a dedicated AGND PCB trace.  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Layout Recommendations  
4.3V<Vin<17V  
Enable  
PVin  
Vin  
EN  
Boot  
Phase  
SW  
VCC/LDO  
VDRV  
Vo  
PGood  
0.1uF  
NC  
PGood  
IR3889  
GATEL  
SS/Latch  
Cff  
RFB1  
Fb  
Ton/Mode  
ILIM  
VSENM  
RFB2  
AGnd  
PGnd NC NC  
NC  
Figure 23  
Single-ended Vo sense configuration  
4.3V<Vin<17V  
Enable  
PVin  
Vin  
EN  
Boot  
Phase  
SW  
VCC/LDO  
VDRV  
Vo  
PGood  
NC  
0.1uF  
PGood  
IR3889  
GATEL  
SS/Latch  
Fb  
Ton/Mode  
ILIM  
Cff  
A pair of Vo sense traces  
run close to each other.  
VSENM  
AGnd  
PGnd NC NC  
NC  
RFB1  
RFB2  
Figure 24  
Pseudo remote Vo sense configuration  
Final Datasheet  
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30 A single-voltage synchronous Buck regulator  
Layout Recommendations  
Following figures illustrate the PCB layout design of the IR3889 standard demo board with pseudo remote Vo  
sense.  
Figure 25  
IR3889 Demo Board Top Layer  
Figure 26  
IR3889 Demo Board Bottom Layer  
Figure 27  
IR3889 Demo Board 2nd Layer (Ground)  
Final Datasheet  
41 of 50  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Layout Recommendations  
Figure 28  
IR3889 Demo Board 3rd Layer (Ground & Signal)  
Figure 29  
IR3889 Demo Board 4th Layer  
Figure 30  
IR3889 Demo Board 5th Layer  
Final Datasheet  
42 of 50  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Layout Recommendations  
15.1  
Solder Mask  
Evaluation has shown that the best overall performance is achieved using the substrate/PCB layout as shown in  
the following figures. PQFN devices should be placed to an accuracy of 0.050 mm on both X and Y axes. Self-  
centering behavior is highly dependent on solders and processes, and experiments should be run to confirm the  
limits of self-centering on specific processes.  
Infineon recommends that larger Power or Land Area pads are Solder Mask Defined (SMD). This allows the  
underlying copper traces to be as large as possible, which helps in terms of current carrying capability and device  
cooling capability. When using SMD pads, the underlying copper traces should be at least 0.05 mm larger (on  
each edge) than the openings in the solder mask. This allows for layers to be misaligned by up to 0.1 mm on both  
axes. Ensure that the solder resist in-between the smaller signal lead areas is at least 0.15 mm wide, due to the  
high x/y aspect ratio of the solder mask strip.  
Figure 31  
Solder mask (all dimensions in mm)  
Final Datasheet  
43 of 50  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Layout Recommendations  
15.2  
Stencil Design  
In most cases, the thickness of a stencil has to be matched to the needs of all components on the PCB. For  
typical integrated QFN or SON packages, stencils with a thickness of 100 µm to 120 µm are recommended.  
Further details and specific stencil design recommendations can be found in the application note  
Recommendations for Board Assembly of Infineon Integrated Packages without Leads. A recommended  
stencil design is shown below. This design is for a stencil thickness of 100 µm.  
Figure 32  
Stencil pad size and spacing (all dimensions in mm)  
Final Datasheet  
44 of 50  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Package  
16  
Package  
This section includes marking, mechanical and packaging information for the IR3889.  
16.1  
Marking Information  
PART NUMBER  
IR3889M  
DATA MATRIX CODE  
LOT CODE  
ASSEMBLY SITE CODE  
PIN 1, IDENTIFIER  
DATE CODE, FORMAT YYWW  
Figure 33  
Package Marking  
16.2  
Dimensions  
Final Datasheet  
45 of 50  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Package  
Figure 34  
Package Dimensions (all dimensions in mm)  
Final Datasheet  
46 of 50  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Package  
16.3  
Tape and Reel Information  
Figure 35  
Pin 1 orientation in the tape  
Final Datasheet  
47 of 50  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Environmental Qualifications  
17  
Environmental Qualifications  
Qualification Level  
Industrial  
Moisture Sensitivity  
QFN Package  
JEDEC Level 2 @ 260 °C  
Human Body Model  
Charged Device Model  
ANSI/ESDA/JEDEC JS-001, 2 (2000 V to < 4000 V)  
ESD  
ANSI/ESDA/JEDEC JS-002, C3 (1000 V)  
RoHS2 Compliant  
This product is in compliance with EU Directive 2015/863/EU  
amending Annex II to EU Directive 2011/65/EU (RoHS) and  
contains Pb according RoHS exemption 7a, Lead in high  
melting temperature type solders.  
Final Datasheet  
48 of 50  
V2.7  
2022-4-4  
IRꢀꢁꢁꢂ OptiMOS™ IPOL  
30 A single-voltage synchronous Buck regulator  
Evaluation Boards and Support Documentation  
18  
Evaluation Boards and Support Documentation  
Table 9 IR3889 Evaluation Boards and User Guides  
Evaluation board  
EVAL_3889_1Vout  
EVAL_3889_3.3Vout  
Specifications  
Website Address  
12 V±10%, 1 V, 30 A  
12 V±10%, 3.3 V, 30 A  
www.infineon.com/EVAL_3889_1Vout  
www.infineon.com/EVAL_3889_3.3Vout  
Table 10 IR3889 Package Information  
Device  
Package Type  
Website Address  
IR3889  
PG-IQFN-36-2  
https://www.infineon.com/cms/en/product/packages/PG-IQFN  
Final Datasheet  
49 of 50  
V2.7  
2022-4-4  
IR3889ꢀOptiMOSªꢀIPOL  
IR3889  
RevisionꢀHistory  
IR3889  
Revision:ꢀ2022-04-11,ꢀRev.ꢀ2.7  
Previous Revision  
Revision Date  
Subjects (major changes since last revision)  
2.0  
2.1  
Initial release  
2019-06-14  
(1) Update Fig 3 & 10; (2) clarify test conditions for SS and Ton and Update typical value  
of Ton; (3) Add OVP falling threshold; (4) Update IVFB spec from +/-0.4uA to +/-0.15uA;  
(5) Add VDRV spec to section 5 and 7.1; (6) Update ESD HBM spec;  
2019-08-20  
2.2  
2.3  
2.4  
2.5  
Correct SS slew rate from 0.4mV/us to 0.2mV/us with SS = floating in EC table  
Update Fig 2  
2019-10-21  
2019-12-15  
2020-01-23  
(1) Update format; (2) Update Fig 2; (3) Correct units in Fig 7 & 8  
(1) Clarify the RoHS compliance spec; (2) Update Junction-Case top thermal  
resistance;(3) Add Table 7  
2020-06-25  
2.6  
(1) Add max Vout of 6V to the recommended operation conditions; (2) Update note 8;  
(3) Update Table 7; (4) Correct test condition of ILIM in EC table from VCC = 5V to int  
LDO; (5) Update order info  
2021-07-27  
2022-04-11  
2.7  
(1) Update Figure 31, 32, 35; (2) Correct typos in test condition of dead band time  
Trademarks  
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50  
Rev.ꢀ2.7,ꢀꢀ2022-04-11  

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