LM5025SD/NOPB [TI]

具有 P 或 N 沟道钳位 FET 和 0.25V CS 阈值的 90V 有源钳位电压模式 PWM 控制器 | NHQ | 16 | -40 to 125;
LM5025SD/NOPB
型号: LM5025SD/NOPB
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

具有 P 或 N 沟道钳位 FET 和 0.25V CS 阈值的 90V 有源钳位电压模式 PWM 控制器 | NHQ | 16 | -40 to 125

控制器 开关 光电二极管
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LM5025  
SNVS265C DECEMBER 2003REVISED JANUARY 2016  
LM5025 Active Clamp Voltage Mode PWM Controller  
1 Features  
3 Description  
The LM5025 PWM controller contains all of the  
1
Internal Start-Up Bias Regulator  
3-A Compound Main Gate Driver  
features necessary to implement power converters  
using the active clamp and reset technique. The  
device can be configured to control either a  
P-channel clamp switch or an N-channel clamp  
switch. With the active clamp technique, higher  
efficiencies and greater power densities can be  
realized compared to conventional catch winding or  
RDC clamp and reset techniques.  
Programmable Line Undervoltage Lockout (UVLO)  
With Adjustable Hysteresis  
Voltage Mode Control With Feed-Forward  
Adjustable Dual-Mode Overcurrent Protection  
Programmable Overlap or Deadtime Between the  
Main and Active Clamp Outputs  
Two control outputs are provided, the main power  
switch control (OUT_A), and the active clamp switch  
control (OUT_B). The active clamp output can be  
configured for either a specified overlap time  
(for P-channel switch applications) or a specified  
deadtime (for N_channel applications). The two  
internal compound gate drivers parallel both MOS  
and bipolar devices, providing superior gate drive  
characteristics. This controller is designed for high-  
speed operation including an oscillator frequency  
range up to 1 MHz and total PWM and current sense  
propagation delays less than 100 ns.  
Volt × Second Clamp  
Programmable Soft-Start  
Leading Edge Blanking  
Single Resistor Programmable Oscillator  
Oscillator UP and DOWN Sync Capability  
Precision 5-V Reference  
Thermal Shutdown  
2 Applications  
Server Power Supplies  
The LM5025 includes  
a
high-voltage start-up  
48-V Telecom Power Supplies  
42-V Automotive Applications  
High-Efficiency DC-to-DC Power Supplies  
regulator that operates over a wide input range of  
13 V to 90 V. Additional features include: line  
undervoltage lockout (UVLO), soft-start, oscillator UP  
and DOWN sync capability, precision reference and  
thermal shutdown.  
Device Information(1)  
PART NUMBER  
LM5025  
PACKAGE  
TSSOP (16)  
WSON (16)  
BODY SIZE (NOM)  
5.00 mm × 4.40 mm  
5 00 mm × 5.00 mm  
(1) For all available packages, see the orderable addendum at  
the end of the data sheet.  
Simplified Schematic  
VOUT  
3.3V  
VIN  
35 - 78V  
LM5025  
CS1  
CS2  
VCC  
9wwhw  
!at &  
VIN  
L{h[!ÇLhb  
UVLO  
OUT_A  
OUT_B  
COMP  
RAMP  
REF  
Rt  
TIME  
SYNC  
SS  
PGND AGND  
UP/DOWN  
SYNC  
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,  
intellectual property matters and other important disclaimers. PRODUCTION DATA.  
 
 
 
 
LM5025  
SNVS265C DECEMBER 2003REVISED JANUARY 2016  
www.ti.com  
Table of Contents  
7.4 Device Functional Modes........................................ 16  
Application and Implementation ........................ 17  
8.1 Application Information............................................ 17  
8.2 Typical Application ................................................. 17  
Power Supply Recommendations...................... 23  
1
2
3
4
5
6
Features.................................................................. 1  
Applications ........................................................... 1  
Description ............................................................. 1  
Revision History..................................................... 2  
Pin Configuration and Functions......................... 3  
Specifications......................................................... 4  
6.1 Absolute Maximum Ratings ...................................... 4  
6.2 ESD Ratings.............................................................. 4  
6.3 Recommended Operating Conditions....................... 4  
6.4 Thermal Information.................................................. 5  
6.5 Electrical Characteristics........................................... 5  
6.6 Typical Characteristics.............................................. 8  
Detailed Description ............................................ 10  
7.1 Overview ................................................................. 10  
7.2 Functional Block Diagram ....................................... 11  
7.3 Feature Description................................................. 12  
8
9
10 Layout................................................................... 23  
10.1 Layout Guidelines ................................................. 23  
10.2 Layout Example .................................................... 23  
11 Device and Documentation Support ................. 24  
11.1 Documentation Support ........................................ 24  
11.2 Community Resources.......................................... 24  
11.3 Trademarks........................................................... 24  
11.4 Electrostatic Discharge Caution............................ 24  
11.5 Glossary................................................................ 24  
7
12 Mechanical, Packaging, and Orderable  
Information ........................................................... 24  
4 Revision History  
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.  
Changes from Revision B (March 2013) to Revision C  
Page  
Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation  
section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and  
Mechanical, Packaging, and Orderable Information section .................................................................................................. 1  
2
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LM5025  
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SNVS265C DECEMBER 2003REVISED JANUARY 2016  
5 Pin Configuration and Functions  
PW and NHQ Packages  
16-Pin TSSOP and WSON  
Top View  
VIN  
RAMP  
CS1  
16  
15  
14  
13  
12  
11  
10  
9
UVLO  
1
2
3
4
5
6
7
8
SYNC  
RT  
CS2  
COMP  
SS  
TIME  
REF  
AGND  
PGND  
OUT_B  
VCC  
OUT_A  
Pin Functions  
PIN  
I/O(1)  
DESCRIPTION  
APPLICATION INFORMATION  
NO.  
NAME  
Input to start-up regulator. Input 13 V to 90 V, with transient capability  
to 100 V.  
1
VIN  
I
Source input voltage  
An external RC circuit from Vin sets the ramp slope. This pin is  
discharged at the conclusion of every cycle by an internal FET,  
initiated by either the internal clock or the V*Sec Clamp comparator.  
2
3
RAMP  
CS1  
I
I
Modulator ramp signal  
If CS1 exceeds 0.25 V the outputs goes into Cycle-by-Cycle current  
limit. CS1 is held low for 50 ns after OUT_A switches high providing  
leading edge blanking.  
Current sense input for  
cycle-by-cycle limiting  
If CS2 exceeds 0.25 V the outputs are disabled and a soft-start  
commences. The soft-start capacitor is fully discharged and then  
released with a pullup current of 1 µA. After the first output pulse  
(when SS = 1 V), the SS charge current reverts back to 20 µA. CS2 is  
held low for 50 ns after OUT_A switches high, providing leading edge  
blanking.  
Current sense input for soft  
restart  
4
CS2  
I
An external resistor (RSET) sets either the overlap time or dead time for  
the active clamp output. An RSET resistor connected between TIME  
and GND produces in-phase OUT_A and OUT_B pulses with overlap.  
An RSET resistor connected between TIME and REF produces out-of-  
phase OUT_A and OUT_B pulses with deadtime.  
Output overlap and deadtime  
control  
5
6
TIME  
REF  
I
Maximum output current: 10-mA locally decouple with a 0.1-µF  
capacitor. Reference stays low until the line UVLO and the VCC UV  
comparators are satisfied.  
Precision 5-V reference  
output  
O
Output from the internal  
high-voltage start-up  
regulator. The VCC voltage is  
regulated to 7.6 V  
If an auxiliary winding raises the voltage on this pin above the  
regulation setpoint, the internal start-up regulator shutdowns, reducing  
the IC power dissipation.  
7
8
VCC  
P
Output of the main switch PWM output gate driver. Output capability of  
3-A peak sink current.  
OUT_A  
O
Main output driver  
Output of the active clamp switch gate driver. Capable of 1.25-A peak  
sink current..  
9
OUT_B  
PGND  
AGND  
O
G
G
Active clamp output driver  
Power ground  
10  
11  
Connect directly to analog ground.  
Connect directly to power ground. For the WSON package option the  
exposed pad is electrically connected to AGND.  
Analog ground  
An external capacitor and an internal 20-µA current source set the soft-  
start ramp. The SS current source is reduced to 1 µA initially following  
a CS2 overcurrent event or an over temperature event.  
12  
SS  
I
Soft-start control  
(1) P = power, G = ground, I = input, O = Output, I/O = Input/output  
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Pin Functions (continued)  
PIN  
I/O(1)  
DESCRIPTION  
APPLICATION INFORMATION  
NO.  
NAME  
Input to the pulse width  
modulator  
An internal 5-Kresistor pullup is provided on this pin. The external  
opto-coupler sinks current from COMP to control the PWM duty cycle.  
13  
COMP  
I
I
An external resistor connected from RT to ground sets the internal  
oscillator frequency.  
14  
15  
RT  
Oscillator timing resistor pin  
The internal oscillator can be synchronized to an external clock with a  
frequency 20% lower than the internal oscillator’s free running  
frequency. There is no constraint on the maximum sync frequency.  
Oscillator UP and DOWN  
synchronization input  
SYNC  
I
I
An external voltage divider from the power source sets the shutdown  
comparator levels. The comparator threshold is 2.5 V. Hysteresis is set  
by an internal current source (20 µA) that is switched on or off as the  
UVLO pin potential crosses the 2.5-V threshold.  
16  
UVLO  
Line undervoltage shutdown  
6 Specifications  
6.1 Absolute Maximum Ratings  
over operating free-air temperature range (unless otherwise noted)(1)  
MIN  
–0.3  
–0.3  
–0.3  
–0.3  
MAX  
100  
16  
UNIT  
VIN to GND  
Input voltage  
VCC to GND  
V
CS1, CS2 to GND  
1
V
V
All other inputs to GND  
Junction temperature, TJ  
Storage temperature, Tstg  
7
150  
150  
°C  
°C  
–55  
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings  
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended  
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.  
6.2 ESD Ratings  
VALUE  
±2000  
±500  
UNIT  
Human-body model (HBM), per ANSI/ESDA/JEDEC JS01(2)  
Charged-device model (CDM), per JEDEC specification JESD22-C101(3)  
V(ESD)  
Electrostatic discharge(1)  
V
(1) For detailed information on soldering plastic TSSOP and WSON packages, refer to the Packaging Data Book.  
(2) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.  
(3) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.  
6.3 Recommended Operating Conditions  
over operating free-air temperature range (unless otherwise noted)  
MIN  
13  
NOM  
MAX  
90  
UNIT  
V
VIN voltage  
External voltage applied to VCC  
Operating junction temperature  
8
15  
V
–40  
125  
°C  
4
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SNVS265C DECEMBER 2003REVISED JANUARY 2016  
6.4 Thermal Information  
LM5025  
THERMAL METRIC(1)  
PW (TSSOP)  
16-PINS  
98.7  
NHQ (WSON)  
UNIT  
16-PINS  
30  
RθJA  
Junction-to-ambient thermal resistance  
Junction-to-case (top) thermal resistance  
Junction-to-board thermal resistance  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
RθJC(top)  
RθJB  
27.8  
25.9  
9.3  
44.3  
ψJT  
Junction-to-top characterization parameter  
Junction-to-board characterization parameter  
Junction-to-case (bottom) thermal resistance  
1.2  
0.2  
ψJB  
43.6  
9.5  
RθJC(bot)  
2.3  
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application  
report, SPRA953.  
6.5 Electrical Characteristics  
Specifications are TJ = 25°C. Unless otherwise specified: VIN = 48 V, VCC = 10 V, RT = 31.3 k, RSET = 27.4 k(1)  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
STARTUP REGULATOR  
VCC Reg  
TJ = 25°C  
7.6  
VCC regulation  
No load  
V
TJ = –40°C to 125°C  
TJ = 25°C  
7.3  
20  
7.9  
25  
VCC current limit(2)  
mA  
µA  
µA  
TJ = –40°C to 125°C  
TJ = 25°C  
I-VIN  
165  
350  
Startup regulator leakage  
(external Vcc Supply)  
VIN = 100 V  
UVLO = 0 V  
TJ = –40°C to 125°C  
TJ = 25°C  
500  
450  
Shutdown current (Iin)  
TJ = –40°C to 125°C  
VCC SUPPLY  
VCC Reg –  
120 mV  
TJ = 25°C  
VCC undervoltage lockout voltage  
(positive going Vcc  
V
)
VCC Reg – 220  
mV  
TJ = –40°C to 125°C  
TJ = 25°C  
1.5  
VCC undervoltage hysteresis  
V
TJ = –40°C to 125°C  
Cgate = 0  
1
4.85  
10  
2
VCC supply current (ICC  
)
TJ = –40°C to 125°C  
4.2  
mA  
REFERENCE SUPPLY  
VREF  
TJ = 25°C  
5
25  
20  
Ref voltage  
IREF = 0 mA  
V
TJ = –40°C to 125°C  
TJ = 25°C  
5.15  
50  
Ref voltage regulation  
Ref current limit  
IREF = 0 to 10 mA  
mV  
mA  
TJ = –40°C to 125°C  
TJ = 25°C  
TJ = –40°C to 125°C  
CURRENT LIMIT  
CS1  
Prop  
CS1 step from 0 to 0.4 V,  
Time to onset of OUT transition (90%),  
Cgate = 0  
40  
50  
CS1 delay to output  
ns  
ns  
CS2  
Prop  
CS2 step from 0 to 0.4 V,  
Time to onset of OUT transition (90%),  
Cgate = 0  
CS2 delay to output  
Leading edge blanking time  
50  
ns  
V
TJ = 25°C  
0.25  
Cycle by cycle threshold voltage  
(CS1)  
TJ = –40°C to 125°C  
0.22  
0.22  
0.28  
0.28  
TJ = 25°C  
TJ = –40°C to 125°C  
0.25  
Cycle skip threshold voltage  
(CS2)  
Resets SS capacitor; auto  
restart  
V
(1) All electrical characteristics having room temperature limits are tested during production with TA = TJ = 25°C. All hot and cold limits are  
specified by correlating the electrical characteristics to process and temperature variations and applying statistical process control.  
(2) Device thermal limitations may limit usable range.  
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SNVS265C DECEMBER 2003REVISED JANUARY 2016  
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Electrical Characteristics (continued)  
Specifications are TJ = 25°C. Unless otherwise specified: VIN = 48 V, VCC = 10 V, RT = 31.3 k, RSET = 27.4 k(1)  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
TJ = 25°C  
30  
CS sink impedance (clocked)  
ICS = 10 mA  
TJ = –40°C to 125°C  
50  
SOFT-START  
TJ = 25°C  
22  
1
Soft-start current source normal  
µA  
µA  
TJ = –40°C to 125°C  
TJ = 25°C  
17  
27  
Soft-start current source following  
a CS2 event  
TJ = –40°C to 125°C  
0.5  
1.5  
OSCILLATOR  
TJ = 25°C  
180  
175  
200  
580  
220  
225  
Frequency1  
Frequency2  
kHz  
kHz  
TJ = –40°C to 125°C  
TJ = 25°C  
RT = 10.4 K  
TJ = –40°C to 125°C  
500  
160  
660  
100  
Sync frequency  
TJ = –40°C to 125°C  
kHz  
V
Sync threshold  
2
Minimum sync pulse width  
TJ = –40°C to 125°C  
ns  
PWM COMPARATOR  
COMP step 5 V to 0 V,  
40  
1
Delay to output  
Duty cycle  
ns  
Time to onset of OUT_A transition low  
TJ = –40°C to 125°C  
TJ = 25°C  
0%  
80%  
COMP to PWM offset  
V
V
TJ = –40°C to 125°C  
TJ = –40°C to 125°C  
0.7  
4.3  
1.3  
5.9  
COMP open circuit voltage  
COMP short circuit current  
TJ = 25°C  
1
COMP = 0 V  
mA  
TJ = –40°C to 125°C  
0.6  
2.4  
1.4  
2.6  
VOLT × SECOND CLAMP  
Delta RAMP measured from  
onset of OUT_A to Ramp  
peak,  
TJ = 25°C  
2.5  
Ramp clamp level  
V
TJ = –40°C to 125°C  
COMP = 5 V  
UVLO SHUTDOWN  
TJ = 25°C  
2.5  
20  
Undervoltage shutdown threshold  
V
TJ = –40°C to 125°C  
TJ = 25°C  
2.44  
16  
2.56  
24  
Undervoltage shutdown  
hysteresis  
µA  
TJ = –40°C to 125°C  
OUTPUT SECTION  
TJ = 25°C  
5
6
OUT_A high saturation  
OUT_A low saturation  
OUT_B high saturation  
OUT_B low saturation  
MOS device at Iout = –10 mA  
MOS device at Iout = 10 mA  
MOS device at Iout = –10 mA  
MOS device at Iout = 10 mA  
TJ = –40°C to 125°C  
TJ = 25°C  
10  
9
TJ = –40°C to 125°C  
TJ = 25°C  
10  
12  
TJ = –40°C to 125°C  
TJ = 25°C  
20  
18  
TJ = –40°C to 125°C  
OUTPUT_B peak current sink  
OUTPUT_A peak current sink  
OUTPUT_A rise time  
Bipolar device at Vcc/2  
Bipolar device at Vcc/2  
Cgate = 2.2 nF  
1
3
A
A
20  
15  
20  
15  
ns  
ns  
ns  
ns  
OUTPUT_A fall time  
Cgate = 2.2 nF  
OUTPUT_B rise time  
Cgate = 1 nF  
OUTPUT_B fall time  
Cgate = 1 nF  
6
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Electrical Characteristics (continued)  
Specifications are TJ = 25°C. Unless otherwise specified: VIN = 48 V, VCC = 10 V, RT = 31.3 k, RSET = 27.4 k(1)  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
105  
105  
MAX  
UNIT  
OUTPUT TIMING CONTROL  
TJ = 25°C  
RSET = 38 kconnected to  
Overlap time  
ns  
ns  
GND, 50% to 50% transitions  
TJ = –40°C to 125°C  
TJ = 25°C  
75  
75  
135  
135  
RSET = 29.5 kconnected to  
Deadtime  
REF, 50% to 50% transitions  
TJ = –40°C to 125°C  
THERMAL SHUTDOWN  
TSD  
Thermal shutdown threshold  
Thermal shutdown hysteresis  
165  
25  
°C  
°C  
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6.6 Typical Characteristics  
16  
10  
8
VIN  
14  
12  
10  
8
6
VCC  
4
6
4
2
2
0
0
0
2
4
6
8
10 12 14 16  
0
5
10  
15  
20  
25  
VIN (V)  
ICC (mA)  
Figure 1. VCC Regulator Start-Up Characteristics, VCC vs Vin  
Figure 2. VCC vs ICC  
1000  
6
5
4
3
2
1
0
100  
1
10  
100  
0
5
10  
15  
20  
25  
IREF (mA)  
RT (kW)  
Figure 3. VREF vs IREF  
Figure 4. Oscillator Frequency vs RT  
140  
400  
350  
300  
250  
200  
150  
100  
50  
130  
120  
110  
100  
90  
80  
0
-40  
25  
75  
125  
0
20  
40  
80  
100 120  
60  
TEMPERATURE (oC)  
RSET (kW)  
Figure 6. Overlap Time vs Temperature RSET = 38 K  
Figure 5. Overlap Time vs RSET  
8
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Typical Characteristics (continued)  
140  
130  
120  
110  
100  
90  
400  
350  
300  
250  
200  
150  
100  
50  
80  
0
-40  
25  
75  
125  
60  
80  
100 120  
0
20  
40  
TEMPERATURE (oC)  
RSET (kW)  
Figure 7. Dead Time vs RSET  
Figure 8. Dead Time vs Temperature RSET = 29.5 K  
26  
24  
22  
20  
18  
16  
14  
-40  
25  
75  
125  
TEMPERATURE (oC)  
Figure 9. SS Pin Current vs Temperature  
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7 Detailed Description  
7.1 Overview  
The LM5025 PWM controller contains all of the features necessary to implement power converters using the  
active clamp reset technique. The device can be configured to control either a P-channel clamp switch or an  
N-channel clamp switch. With the active clamp technique higher efficiencies and greater power densities can be  
realized compared to conventional catch winding or RDC clamp and reset techniques. Two control outputs are  
provided, the main power switch control (OUT_A), and the active clamp switch control (OUT_B). The active  
clamp output can be configured for either a specified overlap time (for P-channel switch applications) or a  
specified dead time (for N_channel applications). The two internal compound gate drivers parallel both MOS and  
bipolar devices, providing superior gate-drive characteristics. This controller is designed for high-speed operation  
including an oscillator frequency range up to 1 MHz and total PWM and current sense propagation delays less  
than 100 ns. The LM5025 includes a high-voltage start-up regulator that operates over a wide input of  
13 V to 90 V. Additional features include: line undervoltage lockout (UVLO), soft-start, oscillator UP and DOWN  
sync capability, precision reference and thermal shutdown.  
10  
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7.2 Functional Block Diagram  
7.6V SERIES  
REGULATOR  
VIN  
VCC  
5V  
REF  
VCC  
UVLO  
REFERENCE  
UVLO  
LOGIC  
+
-
2.5V  
UVLO  
HYSTERESIS  
(20 mA)  
VCC  
OUT_A  
CLK  
RT  
DRIVER  
OSCILLATOR  
SYNC  
RAMP  
SLOPE a TO VIN  
59!5ÇLa9  
hw  
hë9w[!t  
/hbÇwh[  
TIME  
FF RAMP  
VCC  
5V  
5k  
OUT_B  
PWM  
+
-
COMP  
DRIVER  
Q
Q
S
R
1V  
SS Amp  
(Sink Only)  
LOGIC  
SS  
+
-
2.5V  
MAX V*S  
CLAMP  
CS1  
CS2  
PGND  
+
-
0.25V  
+
-
0.25V  
CLK + LEB  
AGND  
SS  
20 mA  
SS  
19 mA  
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7.3 Feature Description  
7.3.1 High-Voltage Start-Up Regulator  
The LM5025 contains an internal high-voltage start-up regulator that allows the input pin (VIN) to be connected  
directly to the line voltage. The regulator output is internally current limited to 20 mA. When power is applied, the  
regulator is enabled and sources current into an external capacitor connected to the VCC pin. The recommended  
capacitance for the VCC regulator is 0.1 µF to 100 µF. When the voltage on the VCC pin reaches the regulation  
point of 7.6 V and the internal voltage reference (REF) reaches its regulation point of 5 V, the controller outputs  
are enabled. The outputs remains enabled until VCC falls below 6.2 V or the line undervoltage lock out detector  
indicates that VIN is out of range. In typical applications, an auxiliary transformer winding is connected through a  
diode to the VCC pin. This winding must raise the VCC voltage above 8 V to shut off the internal start-up regulator.  
Powering VCC from an auxiliary winding improves efficiency while reducing the controller power dissipation.  
The external VCC capacitor must be sized such that the capacitor and VCC self-bias maintains a VCC voltage  
greater than 6.2 V during the initial start-up. During a fault mode when the converter auxiliary winding is inactive,  
external current draw on the VCC line must be limited so the power dissipated in the start-up regulator does not  
exceed the maximum power dissipation of the controller.  
An external start-up regulator or other bias rail can be used instead of the internal start-up regulator by  
connecting the VCC and the VIN pins together and feeding the external bias voltage into the two pins.  
7.3.2 Line Undervoltage Detector  
The LM5025 contains a line undervoltage lock out (UVLO) circuit. An external set-point voltage divider from Vin  
to GND, sets the operational range of the converter. The divider must be designed such that the voltage at the  
UVLO pin is greater than 2.5 V when Vin is in the desired operating range. If the undervoltage threshold is not  
met, all functions of the controller are disabled and the controller remains in a low-power standby state. UVLO  
hysteresis is accomplished with an internal 20-µA current source that is switched on or off into the impedance of  
the set-point divider. When the UVLO threshold is exceeded, the current source is activated to instantly raise the  
voltage at the UVLO pin. When the UVLO pin voltage falls below the 2.5-V threshold, the current source is turned  
off, causing the voltage at the UVLO pin to fall. The UVLO pin can also be used to implement a remote enable  
and disable function. Pulling the UVLO pin below the 2.5-V threshold disables the converter.  
7.3.3 PWM Outputs  
The relative phase of the main (OUT_A) and active clamp outputs (OUT_B) can be configured for the specific  
application. For active clamp configurations using a ground referenced P-channel clamp switch, the two outputs  
must be in phase with the active clamp output overlapping the main output. For active clamp configurations using  
a high side N-channel switch, the active clamp output must be out of phase with main output and there must be a  
dead time between the two gate drive pulses. A distinguishing feature of the LM5025 is the ability to accurately  
configure either dead time (both off) or overlap time (both on) of the gate driver outputs. The overlap and  
deadtime magnitude is controlled by the resistor value connected to the TIME pin of the controller. The opposite  
end of the resistor can be connected to either REF for deadtime control or GND for overlap control. The internal  
configuration detector senses the connection and configures the phase relationship of the main and active clamp  
outputs.  
7.3.4 Compound Gate Drivers  
The LM5025 contains two unique compound gate drivers, which parallel both MOS and bipolar devices to  
provide high-drive current throughout the entire switching event. The bipolar device provides most of the drive  
current capability and provides a relatively constant sink current that is ideal for driving large power MOSFETs.  
As the switching event nears conclusion and the bipolar device saturates, the internal MOS device continues to  
provide a low-impedance to compete the switching event.  
During turnoff at the Miller plateau region, typically around 2 V to 3 V, is where gate driver current capability is  
needed most. The resistive characteristics of all MOS gate drivers are adequate for turnon, because the supply  
to output voltage differential is fairly large at the Miller region. During turnoff however, the voltage differential is  
small and the current source characteristic of the bipolar gate driver is beneficial to provide fast drive capability.  
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Feature Description (continued)  
VCC  
OUT  
CNTRL  
PGND  
Figure 10. Compound Gate Drivers  
7.3.5 PWM Comparator  
The PWM comparator compares the ramp signal (RAMP) to the loop error signal (COMP). This comparator is  
optimized for speed to achieve minimum controllable duty cycles. The internal 5-kpullup resistor, connected  
between the internal 5-V reference and COMP can be used as the pullup for an optocoupler. The comparator  
polarity is such that 0 V on the COMP pin produces a zero-duty cycle on both gate driver outputs.  
7.3.6 Volt Second Clamp  
The volt × second clamp comparator compares the ramp signal (RAMP) to a fixed 2.5-V reference. By proper  
selection of RFF and CFF, the maximum ON time of the main switch can be set to the desired duration. The ON  
time set by volt × second clamp varies inversely with the line voltage because the RAMP capacitor is charged by  
a resistor connected to Vin while the threshold of the clamp is a fixed voltage (2.5 V).  
The CFF ramp capacitor is discharged at the conclusion of every cycle by an internal discharge switch controlled  
by either the internal clock or by the V × S Clamp comparator, whichever event occurs first.  
7.3.7 Current Limit  
The LM5025 contains two modes of overcurrent protection. If the sense voltage at the CS1 input exceeds 0.25 V  
the present power cycle is terminated (cycle-by-cycle current limit). If the sense voltage at the CS2 input exceeds  
0.25 V, the controller terminates the present cycle, discharge the soft-start capacitor and reduce the soft-start  
current source to 1 µA. The soft-start (SS) capacitor is released after being fully discharged and slowly charges  
with a 1-µA current source. When the voltage at the SS pin reaches approximately 1 V, the PWM comparator  
produces the first output pulse at OUT_A. After the first pulse occurs, the soft-start current source reverts to the  
normal 20-µA level. Fully discharging and then slowly charging the SS capacitor protects a continuously  
overloaded converter with a low-duty cycle hiccup mode.  
These two modes of overcurrent protection allows the user great flexibility to configure the system behavior in  
overload conditions. If it is desired for the system to act as a current source during an overload, then the CS1  
cycle-by-cycle current limiting must be used. In this case the current sense signal must be applied to the CS1  
input and the CS2 input must be grounded. If during an overload condition it is desired for the system to briefly  
shutdown, followed by soft-start retry, then the CS2 hiccup current limiting mode must be used. In this case the  
current sense signal must be applied to the CS2 input and the CS1 input must be grounded. This shutdown and  
soft-start retry repeats indefinitely while the overload condition remains. The hiccup mode greatly reduces the  
thermal stresses to the system during heavy overloads. The cycle-by-cycle mode has higher system thermal  
dissipations during heavy overloads, but provides the advantage of continuous operation for short duration  
overload conditions.  
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Feature Description (continued)  
In some systems it is possible use both modes concurrently, whereby slight overload conditions activate the CS1  
cycle-by cycle mode, while more severe overloading activates the CS2 hiccup mode. Operating both modes  
concurrently requires that the slope of the inductor current be sufficient to reach the CS2 threshold before the  
CS1 function turns off the main output switch. This requires a high dv/dt at the current sense pin. The signal  
must be fast enough to reach the second-level threshold before the first threshold detector (CS1) turns off the  
gate driver. Excessive filtering on the CS pin, an extremely low-value current sense resistor or an inductor that  
does not saturate with excessive loading may prevent the second-level threshold from ever being reached.  
TI recommends a small RC filter, located near the controller, for each of the CS pins. Each CS input has an  
internal FET that discharges the current sense filter capacitor at the conclusion of every cycle, to improve  
dynamic performance. This same FET remains on an additional 50 ns at the start of each main switch cycle to  
attenuate the leading edge spike in the current sense signal.  
The LM5025 CS comparators are very fast and may respond to short duration noise pulses. Layout  
considerations are critical for the current sense filter and sense resistor. The capacitor associated with the CS  
filter must be placed very close to the device and connected directly to the pins of the IC (CS and GND). If a  
current sense transformer is used, both leads of the transformer secondary must be routed to the filter network ,  
which must be located close to the IC. If a sense resistor in the source of the main switch MOSFET is used for  
current sensing, a low-inductance type of resistor is required. When designing with a current sense resistor, all of  
the noise sensitive low-power ground connections must be connected together near the IC GND and a single  
connection must be made to the power ground (sense resistor ground point).  
CS2  
20 mA  
SS  
1 mA  
Figure 11. Current Limit  
7.3.8 Oscillator and Sync Capability  
The LM5025 oscillator is set by a single external resistor connected between the RT pin and GND.  
The RT resistor must be located very close to the device and connected directly to the pins of the IC (RT and  
GND).  
A unique feature of LM5025 is the ability to synchronize the oscillator to an external clock with a frequency that is  
either higher or lower than the frequency of the internal oscillator. The lower frequency sync frequency range is  
80% of the free running internal oscillator frequency. There is no constraint on the maximum SYNC frequency. A  
minimum pulse width of 100 ns is required for the synchronization clock . If the synchronization feature is not  
required, the SYNC pin must be connected to GND to prevent any abnormal interference. The internal oscillator  
can be completely disabled by connecting the RT pin to REF. Once disabled, the sync signal acts directly as the  
master clock for the controller. Both the frequency and the maximum duty cycle of the PWM controller can be  
controlled by the SYNC signal (within the limitations of the volt × second clamp). The maximum duty cycle (D) is  
(1D) of the SYNC signal.  
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Feature Description (continued)  
7.3.9 Feed-Forward Ramp  
An external resistor (RFF) and capacitor (CFF) connected to VIN and GND are required to create the PWM ramp  
signal. The slope of the signal at the RAMP pin varies in proportion to the input line voltage. This varying slope  
provides line feedforward information necessary to improve line transient response with voltage mode control.  
The RAMP signal is compared to the error signal at the COMP pin by the pulse width modulator comparator to  
control the duty cycle of the main switch output. The volt second clamp comparator also monitors the RAMP pin  
and if the ramp amplitude exceeds 2.5 V the present cycle is terminated. The ramp signal is reset to GND at the  
end of each cycle by either the internal clock or the volt second comparator, whichever occurs first.  
7.3.10 Soft-Start  
The soft-start feature allows the power converter to gradually reach the initial steady state operating point, thus  
reducing start-up stresses and surges. At power on, a 20-µA current is sourced out of the soft-start pin (SS) into  
an external capacitor. The capacitor voltage ramps up slowly and limits the COMP pin voltage and therefore the  
PWM duty cycle. In the event of a fault as determined by VCC undervoltage, line undervoltage (UVLO), or  
second-level current limit, the output gate drivers are disabled and the soft-start capacitor is fully discharged.  
When the fault condition is no longer present a soft-start sequence is initiated. Following a second-level current  
limit detection (CS2), the soft-start current source is reduced to 1 µA until the first output pulse is generated by  
the PWM comparator. The current source returns to the nominal 20-µA level after the first output pulse  
(approximately 1 V at the SS pin).  
7.3.11 Thermal Protection  
Internal thermal shutdown circuitry is provided to protect the integrated circuit in the event the maximum junction  
temperature is exceeded. When activated, typically at 165°C, the controller is forced into a low-power standby  
state with the output drivers and the bias regulator disabled. The device restarts after the thermal hysteresis  
(typically 25°C). During a restart after thermal shutdown, the soft-start capacitor is fully discharged and then  
charged in the low-current mode (1 µA) similar to a second-level current limit event. The thermal protection  
feature is provided to prevent catastrophic failures from accidental device overheating.  
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7.4 Device Functional Modes  
The LM5025 active clamp voltage mode PWM controller has six functional modes. The modes transition diagram  
is shown in Figure 12.  
UVLO Mode  
Soft-Start Mode  
Normal Operation Mode  
Cycle-by-Cycle Current Limit Mode  
Hiccup Mode  
Thermal Shut Down Mode  
UVLO  
CBC  
Soft Start  
Hiccup  
Normal Operation  
Thermal Shut Down  
Figure 12. Functional Mode Transition Diagram  
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8 Application and Implementation  
NOTE  
Information in the following applications sections is not part of the TI component  
specification, and TI does not warrant its accuracy or completeness. TI’s customers are  
responsible for determining suitability of components for their purposes. Customers must  
validate and test their design implementation to confirm system functionality.  
8.1 Application Information  
The LM5025 PWM controller contains all of the features necessary to implement power converters using the  
active clamp and reset technique. This section provides design guidance for a typical active clamp forward  
converter design. An actual application schematic of a 36-V to 78-V input, 3.3-V, 30-A output active clamp  
forward converter is also provided in Figure 21.  
8.2 Typical Application  
Figure 13 shows a simplified schematic of an active clamp forward power converter.  
Power converters based on the forward topology offer high-efficiency and good power-handling capability in  
applications up to several hundred Watts. The operation of the transformer in a forward topology does not  
inherently self-reset each power switching cycle, a mechanism to reset the transformer is required. The active  
clamp reset mechanism is presently finding extensive use in medium-level power converters in the 50 W to  
200 W range.  
The forward converter is derived from the Buck topology family, employing a single modulating power switch.  
The main difference between the topologies is the forward topology employs a transformer to provide input and  
output ground isolation and a step down or step up function.  
Each cycle, the main primary switch turns on and applies the input voltage across the primary winding. The  
transformer turns the voltage to a lower-level on the secondary side. The clamp capacitor along with the reset  
switch reverse biases the transformer primary each cycle when the main switch turns off. This reverse voltage  
resets the transformer. The clamp capacitor voltage is VIN / (1-D).  
The secondary rectification employs self-driven synchronous rectification to maintain high-efficiency and ease of  
drive.  
Feedback from the output is processed by an amplifier and reference, generating an error voltage, which is  
coupled back to the primary side control through an opto-coupler. The LM5025 voltage mode controller pulse  
width modulates the error signal with a ramp signal derived from the input voltage. Deriving the ramp signal slope  
from the input voltage provides line feed-forward, which improves line transient rejection. The LM5025 also  
provides a controlled delay necessary for the reset switch.  
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Typical Application (continued)  
VOUT  
3.3V  
VIN  
35 - 78V  
LM5025  
CS2  
VCC  
CS1  
9wwhw  
!at &  
VIN  
L{h[!ÇLhb  
UVLO  
OUT_A  
OUT_B  
COMP  
RAMP  
REF  
Rt  
TIME  
PGND  
SYNC  
SS  
AGND  
UP/DOWN  
SYNC  
Figure 13. Simplified Active Clamp Forward Power Converter  
8.2.1 Design Requirements  
This typical application provides an example of a fully-functional power converter based on the active clamp  
forward topology in an industry standard half-brick footprint.  
The design requirements are:  
Input: 36 V to 78 V (100-V peak)  
Output Voltage: 3.3 V  
Output Current: 0 A to 30 A  
Measured Efficiency: 90.5% at 30 A, 92.5% at 15 A  
Frequency of Operation: 230 kHz  
Board Size: 2.3 × 2.4 × 0.5 inches  
Load Regulation: 1%  
Line Regulation: 0.1%  
Line UVLO, Hiccup Current Limit  
8.2.2 Detailed Design Procedure  
Before the controller design begins, the power stage design must be completed. This section describes the  
calculations needed to configure the LM5025 controller to meet the power stage design requirements.  
8.2.2.1 Oscillator  
The desired switching frequency F is set by a resistor connected between RT pin and ground. The resistance  
value RT is calculated from Equation 1:  
RT = (5725/F)1.026  
where  
F is in kHz and RT in kΩ.  
(1)  
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Typical Application (continued)  
8.2.2.2 Soft-Start Ramp Time and Hiccup Interval  
The soft-start ramp time and hiccup internal is programmed by a capacitor (CSS) on the SS pin to ground. The  
soft-start ramp time is determined by comparing the SS pin voltage with COMP pin voltage. When the SS voltage  
is less than COMP voltage, the COMP voltage is clamped by SS voltage. The PWM duty is limited by the  
clamped COMP voltage, so that soft-start can be achieved. The first PWM pulse is generated after COMP  
voltage reaches 1 V. So the soft-start ramp time of the output voltage can be estimated by Equation 2:  
VSS -1 V  
TSS (ms)=CSS (nF) ì  
20mA  
where  
VSS is the steady state COMP pin voltage. This voltage is determined by the output voltage, voltage divider,  
and the compensation network.  
(2)  
In hiccup mode, the SS current source is reduced to 1 µA. When the first PWM pulse is generated, the current  
source switches to 20 µA, and the power supply tries to start up again. The hiccup interval can be calculated by  
Equation 3:  
1 V  
Thiccup (ms)=CSS (nF) ì  
1mA  
(3)  
8.2.2.3 Feed-Forward Ramp and Maximum On Time Clamp  
An example illustrates the use of the Volt × Second Clamp comparator to achieve a 50% duty cycle limit, at 200  
KHz, at a 48-V line input: A 50% duty cycle at a 200 KHz requires a 2.5 µs of ON time. At 48-V input the Volt ×  
Second product is 120 V × µs (48 V × 2.5 µs). To achieve this clamp level, see Equation 4 and Equation 5:  
RFF × CFF = VIN × TON / 2.5 V  
48 × 2.5 µF / 2.5 = 48 µF  
(4)  
(5)  
Select CFF = 470 pF  
RFF = 102 kΩ  
The recommended capacitor value range for CFF is 100 pF to 1000 pF.  
8.2.2.4 Dead Times  
The magnitude of the overlap and dead time can be calculated as follows in Equation 6 and Equation 7:  
Overlap Time (ns) = 2.8 × RSET – 1.2  
(6)  
(7)  
Dead Time (ns) = 2.9 × RSET + 20  
where  
RSET in kΩ, Time in ns  
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Typical Application (continued)  
OUT_A  
K1 x RSET  
P-Channel Active Clamp  
(RSET to GND)  
OUT_B  
OUT_A  
N-Channel Active Clamp  
(RSET to REF)  
K2 x RSET  
OUT_B  
Figure 14. PWM Outputs  
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Typical Application (continued)  
8.2.3 Application Curves  
1
2
1
Conditions: input voltage = 48 VDC, output current = 5 A  
Trace 1: output voltage Volts/div = 0.5 V  
Horizontal resolution = 1 ms/div  
Conditions: input voltage = 48 VDC, output current = 5 A to 25 A  
Trace 1: output voltage Volts/div = 0.5 V  
Trace 2: output current, Amps/div = 10 A  
Horizontal resolution = 1 μs/div  
Figure 15. Output Voltage During Typical Startup  
Figure 16. Transient Response  
1
1
Conditions: input voltage = 48 VDC, output current = 30 A  
Bandwidth limit = 25 MHz  
Conditions: input voltage = 38 VDC, output current = 25 A  
Trace 1: Q1 drain voltage Volts/div = 20 V  
Horizontal resolution = 1 μs/div  
Trace 1: output ripple voltage Volts/div = 50 mV  
Horizontal resolution = 2 μs/div  
Figure 17. Output Ripple  
Figure 18. Drain Voltage  
1
2
1
Conditions: input voltage = 78 VDC, output current = 25 A  
Trace 1: Q1 drain voltage Volts/div = 20 V  
Horizontal resolution = 1 μs/div  
Conditions: input voltage = 48 VDC, output current = 5 A  
Synchronous rectifier, Q3 gate Volts/div = 5 V  
Trace 1: synchronous rectifier, Q3 gate Volts/div = 5 V  
Trace 2: synchronous rectifier, Q5 gate Volts/div = 5 V  
Horizontal resolution = 1 μs/div  
Figure 19. Drain Voltage  
Figure 20. Gate Voltages of the Synchronous Rectifiers  
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Typical Application (continued)  
8.2.4 System Example  
Figure 21 shows an application circuit with 36-V to 78-V input and 3.3-V, 30-A output capability.  
Figure 21. Application Circuit  
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9 Power Supply Recommendations  
VCC pin is the power supply for the device. There must be a 0.1-µF to approximately 100-μF capacitor directly  
from VCC to ground. REF pin must be bypassed to ground as close as possible to the device using a 0.1-μF  
capacitor.  
10 Layout  
10.1 Layout Guidelines  
Connect two grounds PGND (power ground) and AGND (analog ground) directly as device ground ICGND.  
The connection must be as close to the pins as possible.  
If there are multiple PCB layers and there is a inner ground layer, use two vias or one big via on GND and  
connect them to the inner ground layer (ICGND).  
The power stage ground PSGND should be separated with the ICGND. PSGND and ICGND should be  
connected at a single point close to the device.  
The bypass capacitors to the VCC pin and REF pin should be as close as possible to the pins and ground  
(ICGND).  
The filtering capacitors connected to CS1 and CS2 pins should have connections as short as possible to  
ICGND; if an inner ground layer is available, use vias to connect the capacitors to the ground layer (ICGND).  
The resistors and capacitors connected to the timing configuration pins should be as close as possible to the  
pins and ground (ICGND).  
10.2 Layout Example  
Figure 22. LM5025 Layout Recommendation  
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11 Device and Documentation Support  
11.1 Documentation Support  
11.1.1 Related Documentation  
For related documentation, see the following:  
LM5025 Isolated Active Clamp Forward Converter Ref Design User Guide, SNVU096  
11.2 Community Resources  
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective  
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of  
Use.  
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration  
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help  
solve problems with fellow engineers.  
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and  
contact information for technical support.  
11.3 Trademarks  
E2E is a trademark of Texas Instruments.  
All other trademarks are the property of their respective owners.  
11.4 Electrostatic Discharge Caution  
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam  
during storage or handling to prevent electrostatic damage to the MOS gates.  
11.5 Glossary  
SLYZ022 TI Glossary.  
This glossary lists and explains terms, acronyms, and definitions.  
12 Mechanical, Packaging, and Orderable Information  
The following pages include mechanical, packaging, and orderable information. This information is the most  
current data available for the designated devices. This data is subject to change without notice and revision of  
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.  
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PACKAGE OPTION ADDENDUM  
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10-Dec-2020  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
LM5025MTC/NOPB  
LM5025MTCX/NOPB  
LM5025SD/NOPB  
ACTIVE  
TSSOP  
TSSOP  
WSON  
PW  
16  
16  
16  
92  
RoHS & Green  
NIPDAU | SN  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
-40 to 125  
-40 to 125  
-40 to 125  
LM5025  
MTC  
ACTIVE  
ACTIVE  
PW  
2500 RoHS & Green  
1000 RoHS & Green  
NIPDAU | SN  
SN  
LM5025  
MTC  
NHQ  
5025SD  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance  
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may  
reference these types of products as "Pb-Free".  
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.  
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
(6)  
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two  
lines if the finish value exceeds the maximum column width.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
3-Jun-2022  
TAPE AND REEL INFORMATION  
REEL DIMENSIONS  
TAPE DIMENSIONS  
K0  
P1  
W
B0  
Reel  
Diameter  
Cavity  
A0  
A0 Dimension designed to accommodate the component width  
B0 Dimension designed to accommodate the component length  
K0 Dimension designed to accommodate the component thickness  
Overall width of the carrier tape  
W
P1 Pitch between successive cavity centers  
Reel Width (W1)  
QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE  
Sprocket Holes  
Q1 Q2  
Q3 Q4  
Q1 Q2  
Q3 Q4  
User Direction of Feed  
Pocket Quadrants  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LM5025MTCX/NOPB  
LM5025SD/NOPB  
TSSOP  
WSON  
PW  
16  
16  
2500  
1000  
330.0  
178.0  
12.4  
12.4  
6.95  
5.3  
5.6  
5.3  
1.6  
1.3  
8.0  
8.0  
12.0  
12.0  
Q1  
Q1  
NHQ  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
3-Jun-2022  
TAPE AND REEL BOX DIMENSIONS  
Width (mm)  
H
W
L
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LM5025MTCX/NOPB  
LM5025SD/NOPB  
TSSOP  
WSON  
PW  
16  
16  
2500  
1000  
367.0  
208.0  
367.0  
191.0  
35.0  
35.0  
NHQ  
Pack Materials-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
3-Jun-2022  
TUBE  
T - Tube  
height  
L - Tube length  
W - Tube  
width  
B - Alignment groove width  
*All dimensions are nominal  
Device  
Package Name Package Type  
Pins  
SPQ  
L (mm)  
W (mm)  
T (µm)  
B (mm)  
LM5025MTC/NOPB  
LM5025MTC/NOPB  
PW  
PW  
TSSOP  
TSSOP  
16  
16  
92  
92  
495  
530  
8
2514.6  
3600  
4.06  
3.5  
10.2  
Pack Materials-Page 3  
MECHANICAL DATA  
NHQ0016A  
SDA16A (Rev A)  
www.ti.com  
PACKAGE OUTLINE  
PW0016A  
TSSOP - 1.2 mm max height  
S
C
A
L
E
2
.
5
0
0
SMALL OUTLINE PACKAGE  
SEATING  
PLANE  
C
6.6  
6.2  
TYP  
A
0.1 C  
PIN 1 INDEX AREA  
14X 0.65  
16  
1
2X  
5.1  
4.9  
4.55  
NOTE 3  
8
9
0.30  
16X  
4.5  
4.3  
NOTE 4  
1.2 MAX  
0.19  
B
0.1  
C A B  
(0.15) TYP  
SEE DETAIL A  
0.25  
GAGE PLANE  
0.15  
0.05  
0.75  
0.50  
A
20  
0 -8  
DETAIL A  
TYPICAL  
4220204/A 02/2017  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not  
exceed 0.15 mm per side.  
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.  
5. Reference JEDEC registration MO-153.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
PW0016A  
TSSOP - 1.2 mm max height  
SMALL OUTLINE PACKAGE  
SYMM  
16X (1.5)  
(R0.05) TYP  
16  
1
16X (0.45)  
SYMM  
14X (0.65)  
8
9
(5.8)  
LAND PATTERN EXAMPLE  
EXPOSED METAL SHOWN  
SCALE: 10X  
METAL UNDER  
SOLDER MASK  
SOLDER MASK  
OPENING  
SOLDER MASK  
OPENING  
METAL  
EXPOSED METAL  
EXPOSED METAL  
0.05 MAX  
ALL AROUND  
0.05 MIN  
ALL AROUND  
NON-SOLDER MASK  
DEFINED  
SOLDER MASK  
DEFINED  
15.000  
(PREFERRED)  
SOLDER MASK DETAILS  
4220204/A 02/2017  
NOTES: (continued)  
6. Publication IPC-7351 may have alternate designs.  
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
PW0016A  
TSSOP - 1.2 mm max height  
SMALL OUTLINE PACKAGE  
16X (1.5)  
SYMM  
(R0.05) TYP  
16  
1
16X (0.45)  
SYMM  
14X (0.65)  
8
9
(5.8)  
SOLDER PASTE EXAMPLE  
BASED ON 0.125 mm THICK STENCIL  
SCALE: 10X  
4220204/A 02/2017  
NOTES: (continued)  
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
9. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
IMPORTANT NOTICE AND DISCLAIMER  
TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATA SHEETS), DESIGN RESOURCES (INCLUDING REFERENCE  
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”  
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY  
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD  
PARTY INTELLECTUAL PROPERTY RIGHTS.  
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate  
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable  
standards, and any other safety, security, regulatory or other requirements.  
These resources are subject to change without notice. TI grants you permission to use these resources only for development of an  
application that uses the TI products described in the resource. Other reproduction and display of these resources is prohibited. No license  
is granted to any other TI intellectual property right or to any third party intellectual property right. TI disclaims responsibility for, and you  
will fully indemnify TI and its representatives against, any claims, damages, costs, losses, and liabilities arising out of your use of these  
resources.  
TI’s products are provided subject to TI’s Terms of Sale or other applicable terms available either on ti.com or provided in conjunction with  
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TI objects to and rejects any additional or different terms you may have proposed. IMPORTANT NOTICE  
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Copyright © 2022, Texas Instruments Incorporated  

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