MCP1662T-E/OT [MICROCHIP]

High-Voltage Step-Up LED Driver with UVLO and Open Load Protection;
MCP1662T-E/OT
型号: MCP1662T-E/OT
厂家: MICROCHIP    MICROCHIP
描述:

High-Voltage Step-Up LED Driver with UVLO and Open Load Protection

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中文:  中文翻译
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MCP1662  
High-Voltage Step-Up LED Driver with UVLO and Open Load Protection  
Features  
General Description  
• 36V, 800 mIntegrated Switch  
• Up to 92% Efficiency  
The MCP1662 device is a compact, space-efficient,  
fixed-frequency, non-synchronous step-up converter  
optimized to drive LED strings with constant current  
from a two- or three-cell alkaline or lithium Energizer®,  
or NiMH/NiCd, or one-cell Lithium-Ion or Li-Polymer  
batteries.  
• Drive LED Strings in Constant Current  
• 1.3A Peak Input Current Limit:  
- ILED up to 200 mA @ 5.0V VIN, 4 White LEDs  
- ILED up to 125 mA @ 3.3V VIN, 4 White LEDs  
- ILED up to 100 mA @ 4.2V VIN, 8 White LEDs  
• Input Voltage Range: 2.4V to 5.5V  
• Feedback Voltage Reference: VFB = 300 mV  
• Undervoltage Lockout (UVLO):  
The device integrates a 36V, 800 mlow-side switch,  
which is protected by the 1.3A cycle-by-cycle inductor  
peak current limit operation. All compensation and pro-  
tection circuitry is integrated to minimize the number of  
external components.  
The internal feedback (VFB) voltage is set to 300 mV for  
low power dissipation when sensing and regulating the  
LED current. A single resistor sets the LED current.  
- UVLO @ VIN Rising: 2.3V, typical  
- UVLO @ VIN Falling: 1.85V, typical  
• Sleep Mode with 20 nA Typical Quiescent Current  
• PWM Operation: 500 kHz Switching Frequency  
• Cycle-by-Cycle Current Limiting  
The device features an Undervoltage Lockout (UVLO)  
that avoids start-up with low inputs or discharged bat-  
teries for two-cell-powered applications.  
• Internal Compensation  
There is an open load protection (OLP) which turns off  
the operation in situations when the LED string is acci-  
dentally disconnected or the feedback pin is short-cir-  
cuited to GND.  
• Open Load Protection (OLP) in the Event of:  
- Feedback pin shorted to GND (prevent  
excessive current into LEDs)  
- Disconnected LED string (prevent overvoltage  
to the converter’s Output and SW pin)  
For standby applications (EN = GND), the device stops  
switching, enters into Sleep mode and consumes  
20 nA typical of input current.  
• Overtemperature Protection  
• Available Packages:  
- 5-Lead SOT-23  
Package Types  
- 8-Lead 2x3 TDFN  
MCP1662  
SOT-23  
Applications  
• Two and Three-Cell Alkaline or NiMH/NiCd White  
LED Driver for Backlighting Products  
SW  
GND  
VFB  
VIN  
EN  
1
2
3
5
4
• Li-Ion Battery LED Lighting Application  
• Camera Flash  
• LED Flashlights and Backlight Current Source  
• Medical Equipment  
MCP1662  
2x3 TDFN*  
• Portable Devices:  
VFB  
EN  
- Handheld Gaming Devices  
- GPS Navigation Systems  
- LCD Monitors  
1
8
PGND  
2
3
4
7
6
5
S
EP  
9
GND  
SW  
NC  
VIN  
- Portable DVD Players  
NC  
* Includes Exposed Thermal Pad (EP); see  
Table 3-1.  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 1  
MCP1662  
Typical Application  
D
L
MBR0540  
4.7 – 10 µH  
VOUT  
LED1  
LED2  
CIN  
4.7 – 30 µF  
SW  
VIN  
2.4V – 3.0V  
VIN  
0.3V  
COUT  
10 µF  
+
ILED =  
RSET  
MCP1662  
EN  
LED6  
-
VFB  
ON  
VFB = 0.3V  
+
RSET  
12  
OFF  
GND  
ILED = 25 mA  
-
L
L
= 4.7 µH for maximum 4 white LEDs  
= 10 µH for 5 to 10 white LEDs  
CIN = 4.7-10 µF for VIN > 2.5V  
CIN = 20-30 µF for VIN < 2.5V  
Maximum LED Current in Regulation vs. Input Voltage, TA = + 25°C  
250  
200  
150  
100  
50  
4 wLEDs, L = 4.7 µH  
8 wLEDs, L = 10 µH  
0
2
2.5  
3
3.5  
4
4.5  
5
5.5  
VIN (V)  
DS20005316E-page 2  
2014-2015 Microchip Technology Inc.  
MCP1662  
Notice: Stresses above those listed under “Maximum  
Ratings” may cause permanent damage to the device.  
This is a stress rating only and functional operation of  
the device at those or any other conditions above those  
indicated in the operational sections of this specifica-  
tion is not intended. Exposure to maximum rating con-  
ditions for extended periods may affect device  
reliability.  
1.0  
ELECTRICAL  
CHARACTERISTICS  
Absolute Maximum Ratings †  
V
– GND.....................................................................+36V  
SW  
EN, V – GND...............................................................+6.0V  
IN  
V
...............................................................................+0.35V  
FB  
Power Dissipation .......................................Internally Limited  
Storage Temperature .................................... -65 C to +150 C  
Ambient Temperature with Power Applied .... -40 C to +125 C  
Operating Junction Temperature................... -40 C to +150 C  
ESD Protection on All Pins:  
°
°
°
°
°
°
HBM.................................................................4 kV  
MM..................................................................300V  
DC AND AC CHARACTERISTICS  
Electrical Specifications: Unless otherwise specified, all limits apply for typical values at ambient temperature  
TA = +25°C, VIN = 3.3V, VOUT = 9V or 3 white LEDs (VF = 2.75V @ IF = 20 mA or VF = 3.1V @ IF = 100 mA),  
ILED = 20 mA, CIN = COUT = 10 µF, X7R ceramic, L = 4.7 µH.  
Boldface specifications apply over the controlled TA range of -40°C to +125°C.  
Parameters  
Sym.  
Min.  
Typ.  
Max.  
Units  
Conditions  
Note 1  
Input Voltage Range  
VIN  
2.4  
2.3  
1.85  
5.5  
V
V
Undervoltage Lockout (UVLO)  
UVLOSTART  
UVLOSTOP  
VOUTmax  
IOUT  
VIN rising, ILED = 20 mA  
VIN falling, ILED = 20 mA  
V
Maximum Output Voltage  
Maximum Output Current  
32  
V
100  
125  
200  
300  
50  
mA  
mA  
mA  
mV  
mV  
4.2V VIN, 8 LEDs  
3.3V VIN, 4 LEDs  
5.0V VIN, 4 LEDs  
Feedback Voltage Reference  
VFB  
275  
325  
Feedback Open Load  
VFB_OLP  
VFB falling (Note 2)  
Protection (OLP) Threshold  
Feedback Input Bias Current  
Shutdown Quiescent Current  
IVFB  
0.005  
0.02  
1.3  
µA  
µA  
A
IQSHDN  
IN(MAX)  
EN = GND  
NMOS Peak Switch Current  
Limit  
Note 2  
NMOS Switch Leakage  
INLK  
0.4  
0.8  
µA  
VIN = VSW = 5V;  
VOUT = 5.5V  
VEN = VFB = GND  
NMOS Switch ON Resistance  
RDS(ON)  
VIN = 5V,  
I
LED = 100 mA,  
4 series white LEDs  
(Note 2)  
Feedback Voltage  
Line Regulation  
|(VFB/VFB)/VIN|  
0.25  
%/V  
VIN = 3.0V to 5V  
Maximum Duty Cycle  
Switching Frequency  
EN Input Logic High  
DCMAX  
fSW  
425  
85  
90  
500  
575  
%
Note 2  
kHz  
±15%  
VIH  
% of VIN  
Note 1: Minimum input voltage in the range of VIN (VIN < 5.5V < VOUT) depends on the maximum duty cycle  
(DCMAX) and on the output voltage (VOUT), according to the boost converter equation:  
VINmin = VOUT x (1 – DCMAX). Output voltage is equal to the LED voltage plus the voltage on the sense  
resistor (VOUT = VLED + V_RSET).  
2: Determined by characterization, not production tested.  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 3  
MCP1662  
DC AND AC CHARACTERISTICS (CONTINUED)  
Electrical Specifications: Unless otherwise specified, all limits apply for typical values at ambient temperature  
TA = +25°C, VIN = 3.3V, VOUT = 9V or 3 white LEDs (VF = 2.75V @ IF = 20 mA or VF = 3.1V @ IF = 100 mA),  
ILED = 20 mA, CIN = COUT = 10 µF, X7R ceramic, L = 4.7 µH.  
Boldface specifications apply over the controlled TA range of -40°C to +125°C.  
Parameters  
Sym.  
Min.  
Typ.  
Max.  
Units  
Conditions  
EN Input Logic Low  
EN Input Leakage Current  
Start-up Time  
VIL  
IENLK  
tSS  
7.5  
% of VIN  
µA  
0.025  
100  
VEN = 5V  
µs  
EN Low-to-High,  
90% of ILED  
(Note 2, Figure 2-10)  
Thermal Shutdown  
Die Temperature  
TSD  
150  
15  
°C  
°C  
Die Temperature Hysteresis  
TSDHYS  
Note 1: Minimum input voltage in the range of VIN (VIN < 5.5V < VOUT) depends on the maximum duty cycle  
(DCMAX) and on the output voltage (VOUT), according to the boost converter equation:  
VINmin = VOUT x (1 – DCMAX). Output voltage is equal to the LED voltage plus the voltage on the sense  
resistor (VOUT = VLED + V_RSET).  
2: Determined by characterization, not production tested.  
TEMPERATURE SPECIFICATIONS  
Electrical Specifications: Unless otherwise specified, all limits apply for typical values at ambient temperature  
TA = +25°C, VIN = 3.0V, IOUT = 20 mA, VOUT = 12V, CIN = COUT = 10 µF, X7R ceramic, L = 4.7 µH.  
Boldface specifications apply over the air-forced TA range of -40°C to +125°C.  
Parameters  
Sym.  
Min.  
Typ.  
Max.  
Units  
Conditions  
Temperature Ranges  
Operating Junction Temperature  
Range  
TJ  
-40  
+125  
°C  
Steady State  
Storage Temperature Range  
TA  
TJ  
-65  
+150  
+150  
°C  
°C  
Maximum Junction Temperature  
Package Thermal Resistances  
Thermal Resistance, 5L-SOT-23  
Thermal Resistance, 8L 2x3 TDFN  
Transient  
JA  
JA  
201.0  
52.5  
°C/W  
°C/W  
DS20005316E-page 4  
2014-2015 Microchip Technology Inc.  
MCP1662  
2.0  
TYPICAL PERFORMANCE CURVES  
Note: The graphs and tables provided following this note are a statistical summary based on a limited number of  
samples and are provided for informational purposes only. The performance characteristics listed herein  
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified  
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.  
Note: Unless otherwise indicated: VIN = 3.3V, ILED = 20 mA, VOUT = 12V or 4 white LEDs (VF = 2.75V @ IF = 20 mA or  
VF = 3.1V @ IF = 100 mA), CIN = COUT = 10 µF, X7R ceramic, L = 4.7 µH.  
100  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
150  
125  
100  
75  
4 x wLED, L = 4.7 µH  
RSET = 2.2ȍ  
RSET = 3.2ȍ  
VIN = 5.5V  
VIN = 4.0V  
VIN = 3.0V  
RSET = 6.2ȍ  
RSET = 15ȍ  
50  
L = 4.7 µH,  
4 wLEDs  
25  
0
2.3 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5  
Input Voltage (V)  
0
25 50 75 100 125 150 175 200 225 250  
ILED (mA)  
FIGURE 2-1:  
4 White LEDs, ILED vs. VIN.  
FIGURE 2-4:  
ILED  
4 White LEDs, Efficiency vs.  
.
100  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
120  
100  
80  
4 x wLED, L = 4.7 µH, VIN = 3.3V  
RSET = 3.2ȍ  
VIN = 5.5V  
VIN = 3.0V  
VIN = 4.0V  
60  
RSET = 6.2ȍ  
RSET = 15ȍ  
40  
L = 10 µH,  
8 wLEDs  
20  
0
0
20  
40  
60  
80 100 120 140 160  
-40 -25 -10  
5
20 35 50 65 80 95 110 125  
ILED (mA)  
Ambient Temperature (oC)  
FIGURE 2-5:  
8 White LEDs, Efficiency vs.  
FIGURE 2-2:  
Ambient Temperature.  
4 White LEDs, ILED vs.  
ILED  
.
300  
250  
200  
150  
100  
50  
120  
8 x wLED, L = 10 µH, VIN = 4.2V  
RSET = 3.2ȍ  
100  
80  
60  
40  
20  
0
5 wLEDs, L = 10 µH  
2 wLEDs, L = 4.7 µH  
4 wLEDs, L = 4.7 µH  
8 wLEDs, L = 10 µH  
RSET = 6.2ȍ  
RSET = 15ȍ  
0
2.3 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5  
Input Voltage (V)  
-40 -25 -10  
5
20 35 50 65 80 95 110 125  
Ambient Temperature (oC)  
FIGURE 2-6:  
Maximum ILED vs. VIN.  
FIGURE 2-3:  
8 White LEDs, ILED vs.  
Ambient Temperature.  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 5  
MCP1662  
Note: Unless otherwise indicated: VIN = 3.3V, ILED = 20 mA, VOUT = 12V or 4 white LEDs (VF = 2.75V @ IF = 20 mA or  
VF = 3.1V @ IF = 100 mA), CIN = COUT = 10 µF, X7R ceramic, L = 4.7 µH.  
2.5  
250  
200  
150  
100  
50  
2.4  
2.3  
2.2  
2.1  
2
Blue Bars - ILED = 20 mA  
Red Bars - ILED = 40 mA  
UVLO Start  
UVLO Stop  
1.9  
1.8  
1.7  
1.6  
1.5  
0
3
4
5
6
7
8
-40 -25 -10  
5
20 35 50 65 80 95 110 125  
Ambient Temperature (oC)  
Number of LEDs  
FIGURE 2-7:  
Undervoltage Lockout  
FIGURE 2-10:  
Soft Start Time vs. Number  
(UVLO) vs. Ambient Temperature.  
of LEDs.  
50  
40  
30  
20  
10  
3 LEDs, I  
= 20 mA  
LED  
I
LED  
10 mA/div  
V
EN  
2V/div  
V
2V/div  
IN  
0
2.2 2.5 2.8 3.1 3.4 3.7 4.0 4.3 4.6 4.9 5.2 5.5  
Input Voltage (V)  
40 µs/div  
FIGURE 2-8:  
Shutdown Quiescent  
FIGURE 2-11:  
Start-Up When  
Current, IQSHDN, vs. VIN (EN = GND).  
VIN = VENABLE.  
550  
3 LED, I  
= 20 mA  
LED  
525  
500  
475  
450  
I
LED  
10 mA/div  
V
EN  
2V/div  
V
2V/div  
IN  
-40 -25 -10  
5
20 35 50 65 80 95 110 125  
40 µs/div  
Ambient Temperature (°C)  
FIGURE 2-9:  
Switching Frequency, fSW  
FIGURE 2-12:  
Start-Up After Enable.  
vs. Ambient Temperature.  
DS20005316E-page 6  
2014-2015 Microchip Technology Inc.  
MCP1662  
Note: Unless otherwise indicated: VIN = 3.3V, ILED = 20 mA, VOUT = 12V or 4 white LEDs (VF = 2.75V @ IF = 20 mA or  
VF = 3.1V @ IF = 100 mA), CIN = COUT = 10 µF, X7R ceramic, L = 4.7 µH.  
3 LEDs  
3 LEDs  
VOUT  
3V/div  
ILED  
10 mA/div  
VSW  
4V/div  
VSW  
4V/div  
ILED  
20 mA/div  
VEN  
3V/div  
1 µs/div  
2 ms/div  
FIGURE 2-13:  
100 Hz PWM Dimming, 15%  
FIGURE 2-16:  
3.3V Input, 20 mA 3 White  
Duty Cycle.  
LEDs PWM Discontinuous Mode Waveforms.  
3 LEDs  
3 LEDs  
ILED  
100 mA/div  
VOUT  
3V/div  
VSW  
4V/div  
ILED  
50 mA/div  
VSW  
4V/div  
VEN  
3V/div  
1 µs/div  
2 ms/div  
FIGURE 2-14:  
100 Hz PWM Dimming, 85%  
FIGURE 2-17:  
3.3V Input, 100 mA 3 White  
Duty Cycle.  
LEDs PWM Continuous Mode Waveforms.  
3 LEDs  
VFB  
300 mV/div  
ILED  
10 mA/div  
VSW  
4V/div  
50 ms/div  
FIGURE 2-15:  
Open Load (LED Fail or FB  
to GND) Response.  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 7  
MCP1662  
3.0  
PIN DESCRIPTIONS  
The descriptions of the pins are listed in Table 3-1.  
TABLE 3-1:  
PIN FUNCTION TABLE  
MCP1662  
MCP1662  
SOT-23  
Symbol  
Description  
2x3 TDFN  
3
1
1
2
VFB  
SGND  
SW  
Feedback Voltage Pin  
Signal Ground Pin  
3
Switch Node, Boost Inductor Input Pin  
Not Connected  
5
4, 6  
5
NC  
VIN  
Input Voltage Pin  
4
7
PGND  
EN  
Power Ground Pin  
8
Enable Control Input Pin  
Exposed Thermal Pad (EP); must be connected to Ground  
Ground Pin  
2
9
EP  
GND  
3.1  
Feedback Voltage Pin (V  
)
3.7  
Enable Pin (EN)  
FB  
The VFB pin is used to regulate the voltage across the  
RSET sense resistor to 300 mV to keep the output LED  
current in regulation. Connect the cathode of the LED  
to the VFB pin.  
The EN pin is a logic-level input used to enable or dis-  
able device switching and lower quiescent current  
while disabled. A logic high (>85% of VIN) will enable  
the regulator output. A logic low (<7.5% of VIN) will  
ensure that the regulator is disabled.  
3.2  
Signal Ground Pin (S  
)
GND  
3.8  
Exposed Thermal Pad (EP)  
The signal ground pin is used as a return for the inte-  
grated reference voltage and error amplifier. The signal  
ground and power ground must be connected exter-  
nally in one point.  
There is no internal electrical connection between the  
Exposed Thermal Pad (EP) and the SGND and PGND  
pins. They must be connected to the same potential on  
the Printed Circuit Board (PCB).  
3.3  
Switch Node Pin (SW)  
3.9  
Ground Pin (GND)  
Connect the inductor from the input voltage to the SW  
pin. The SW pin carries inductor current and has a typ-  
ical value of 1.3A peak. The integrated N-Channel  
switch drain is internally connected to the SW node.  
The ground or return pin is used for circuit ground con-  
nection. The length of the trace from the input cap  
return, the output cap return and the GND pin must be  
as short as possible to minimize noise on the GND pin.  
The 5-lead SOT-23 package uses a single ground pin.  
3.4  
Not Connected (NC)  
This is an unconnected pin.  
3.5  
Power Supply Input Voltage Pin  
(V )  
IN  
Connect the input voltage source to VIN. The input  
source should be decoupled from GND with a 4.7 µF  
minimum capacitor.  
3.6  
Power Ground Pin (P  
)
GND  
The power ground pin is used as a return for the  
high-current N-Channel switch. The PGND and SGND  
pins are connected externally. The signal ground and  
power ground must be connected externally in one  
point.  
DS20005316E-page 8  
2014-2015 Microchip Technology Inc.  
MCP1662  
4.2  
Functional Description  
4.0  
4.1  
DETAILED DESCRIPTION  
Device Overview  
The MCP1662 is a compact, high-efficiency, fixed  
500 kHz frequency, step-up DC-DC converter. It oper-  
ates as a constant current generator for applications  
powered by two- or three-cell alkaline or lithium Ener-  
gizer® batteries, or three-cell NiCd or NiMH batteries,  
or one-cell Lithium-Ion or Li-Polymer batteries.  
The MCP1662 device is a fixed-frequency, synchro-  
nous step-up converter, with a low-voltage reference of  
300 mV, optimized to keep the output current constant  
by regulating the voltage across the feedback resistor  
(RSET). The MCP1662 integrates a peak current mode  
architecture. It delivers high-efficiency conversion for  
an LED lighting application when it is powered by two-  
or three-cell alkaline, lithium, NiMH, NiCd, or single-cell  
Lithium-Ion batteries. The maximum input voltage is  
5.5V. A high level of integration lowers total system  
cost, eases implementation and reduces board area.  
Figure 4-1 depicts the functional block diagram of the  
MCP1662. It incorporates a Current mode control  
scheme, in which the PWM ramp signal is derived from  
the NMOS power switch current (VSENSE). This ramp  
signal adds a slope ramp compensation signal (VRAMP  
and is compared to the output of the error amplifier  
(VERROR) to control the “on” time of the power switch.  
)
The conventional boost converter with a high-voltage  
reference has a high-voltage drop across the LED  
series current limit resistor. The power dissipated in this  
resistor, which is usually in series with the LED string,  
reduces the total efficiency conversion of an LED driver  
solution. Therefore, the voltage drop on the sense  
resistor (RSET) that is used to regulate the LED current  
must be low. In the case of MCP1662, the VFB value is  
300 mV.  
The device features controlled start-up voltage  
(UVLOSTART = 2.3V) and open load protection, in case  
the LED fails or a short circuit of the VFB pin to GND  
occurs. If the VFB voltage drops to 50 mV typical, the  
device stops switching and the output voltage will be  
equal to the input voltage (minus a diode drop voltage).  
This feature prevents damage to the device and LEDs  
when there is an accidental drop in voltage.  
The 800 m, 36V integrated switch is protected by the  
1.3A cycle-by-cycle inductor peak current limit opera-  
tion. When the Enable pin is pulled to ground  
(EN = GND), the device stops switching, enters into  
Shutdown mode and consumes less than 50 nA of  
input current (Figure 2-8).  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 9  
MCP1662  
SW  
VIN  
Internal Bias  
UVLO_COMP  
VBIAS  
VUVLO_REF  
VIN_OK  
Overcurrent Comparator  
GateDrive  
and  
OCREF  
VLIMIT  
-
Shutdown  
Control  
Logic  
EN  
+
VEXT  
VSENSE  
+
-
+
S
VRAMP  
Slope  
Compensation  
Oscillator  
CLK  
+
GND  
+
VPWM  
Logic  
SR Latch  
VERROR  
QN  
-
EA  
+ 300 mV  
-
VFB  
Rc  
Cc  
Open Load Comparator  
V
+
OLP_REF  
VOLP_REF  
300 mV  
VFB  
-
VUVLO_REF  
VFB_FAULT  
VOUT_OK  
VFB  
VIN_OK  
EN  
Power Good  
Comparator  
and Delay  
Bandgap  
Thermal  
Shutdown  
FIGURE 4-1:  
MCP1662 Simplified Block Diagram.  
DS20005316E-page 10  
2014-2015 Microchip Technology Inc.  
MCP1662  
4.2.1  
INTERNAL BIAS  
4.2.4.1  
Shutdown Mode.  
Input to Output Path (EN = GND)  
The MCP1662 gets its bias from VIN. The VIN bias is  
used to power the device and drive circuits over the  
entire operating range.  
In Shutdown mode, the MCP1662 device stops switch-  
ing and all internal control circuitry is switched off. The  
input voltage will be bypassed to output through the  
inductor and the Schottky diode.  
4.2.2  
START-UP  
The MCP1662 is capable of starting from two alkaline  
cells. MCP1662 starts switching at approximately 2.3V  
typical for a light load current. Once started, the device  
will continue to operate down to 1.85V, typical.  
While the device stops switching, VOUT is equal to the  
output capacitor voltage, which slowly discharges on  
the leak path (from VOUT to a value close to VIN) after  
the LEDs are turned off.  
The start-up time is dependent on the LED’s current, on  
the number of LEDs connected at output, and on the  
output capacitor value (see Figure 2-10).  
In Shutdown mode, the current consumed by the  
MCP1662 device from batteries is very low (below  
50 nA over VIN range; see Figure 2-8).  
Due to the direct path from input to output, in the case  
of pulsing enable applications (EN voltage switches  
from low-to-high) the output capacitor is already  
charged and the output starts from a value close to the  
input voltage.  
4.2.5  
PWM MODE OPERATION  
The MCP1662 operates as a fixed-frequency, non-syn-  
chronous converter. The switching frequency is main-  
tained with a precision oscillator at 500 kHz.  
The internal oscillator has a delayed start to let the out-  
put capacitor completely charge to the input voltage  
value.  
Lossless current sensing converts the peak current sig-  
nal to a voltage (VSENSE) and adds it to the internal  
slope compensation (VRAMP). This summed signal is  
compared to the voltage error amplifier output (VER-  
ROR) to provide a peak current control signal (VPWM) for  
the PWM. The slope compensation signal depends on  
the input voltage. Therefore, the converter provides the  
proper amount of slope compensation to ensure stabil-  
ity. The peak limit current is set to 1.3A.  
4.2.3  
UNDERVOLTAGE LOCKOUT  
(UVLO)  
MCP1662 features an UVLO which prevents fault oper-  
ation below 1.85V typical, which corresponds to the  
value of two discharged alkaline batteries.  
Essentially, there is a hysteresis comparator which  
monitors VIN at the reference voltage derived from the  
bandgap.  
4.2.6  
INTERNAL COMPENSATION  
The error amplifier, with its associated compensation  
network, completes the closed-loop system by compar-  
ing the output voltage to a reference at the input of the  
error amplifier and by feeding the amplified signal to the  
control input of the inner current loop. The compensa-  
tion network provides phase leads and lags at appropri-  
ate frequencies to cancel excessive phase lags and  
leads of the power circuit. All necessary compensation  
components and slope compensation are integrated.  
The device starts its normal operation at 2.3V typical  
input, which corresponds to the voltage value of two  
rechargeable Ni-MH or Ni-Cd cells. A hysteresis is set  
to avoid input transients (temporary VIN drop), which  
might trigger the lower UVLO threshold and restart the  
device.  
When the input voltage is below the UVLOSTART  
threshold, the device is operating with limited specifica-  
tion.  
4.2.4  
ENABLE PIN  
The MCP1662 device enables switching when the EN  
pin is set high. The device is put into Shutdown mode  
when the EN pin is set low. To enable the boost con-  
verter, the EN voltage level must be greater than 85%  
of the VIN voltage. To disable the boost converter, the  
EN voltage must be less than 7.5% of the VIN voltage.  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 11  
MCP1662  
4.2.7  
OPEN LOAD PROTECTION (OLP)  
4.2.9  
OUTPUT SHORT CIRCUIT  
CONDITION  
An internal VFB fault signal turns off the PWM signal  
(VEXT) when output goes out of regulation and one of  
the following occurs:  
Like all non-synchronous boost converters, the  
MCP1662 inductor current will increase excessively  
during a short circuit on the converter’s output. A short  
circuit on the output will cause the diode rectifier to fail,  
the inductor’s temperature to rise, and the saturation  
current to decrease, further increasing the peak cur-  
rent. When the diode fails, the SW pin becomes a  
high-impedance node: it remains connected only to the  
inductor and the resulting excessive ringing may cause  
damage to the MCP1662 device.  
• open load (LED string fails)  
• short circuit of the feedback pin to GND  
In any of the above events, for a regular integrated cir-  
cuit (IC) without any protection implemented, the VFB  
voltage drops to ground potential, its N-channel transis-  
tor is forced to switch at full duty cycle and VOUT rises.  
This fault event may cause the SW pin to exceed its  
maximum voltage rating and may damage the boost  
regulator IC, its external components and the LEDs. To  
avoid these, MCP1662 has implemented an open load  
protection (OLP) which turns off PWM switching when  
such a condition is detected. There is an overvoltage  
comparator with 50 mV reference which monitors the  
VFB voltage.  
4.2.10  
OVERTEMPERATURE  
PROTECTION  
Overtemperature protection circuitry is integrated into  
the MCP1662 device. This circuitry monitors the device  
junction temperature and shuts the device off if the tem-  
perature exceeds +150°C. The device will automati-  
cally restart when the junction temperature drops by  
15°C. The OLP is disabled during an overtemperature  
condition.  
If the OLP event occurs with the input voltage below  
the UVLOSTART threshold and VFB remains under  
50 mV due to weak input (discharged batteries) or an  
overload condition, the device latches its output; it  
resumes after power-up.  
The OLP comparator is disabled during start-up  
sequences and thermal shutdown. Because the OLP  
comparator is turned off during start-up, care must be  
taken when using PWM dimming on the EN pin, as this  
might damage the device if a fault event occurs.  
4.2.8  
OVERCURRENT LIMIT  
The MCP1662 device uses a 1.3A cycle-by-cycle input  
current limit to protect the N-channel switch. There is  
an overcurrent comparator which resets the drive latch  
when the peak of the inductor current reaches the limit.  
In current limitation, the output voltage and load current  
start dropping.  
DS20005316E-page 12  
2014-2015 Microchip Technology Inc.  
MCP1662  
5.2.2  
PWM DIMMING  
5.0  
5.1  
APPLICATION INFORMATION  
Typical Applications  
LED brightness can also be controlled by setting the  
maximum current for the LED string (using Equation 5-1)  
and by lowering it in small steps with a variable duty  
cycle PWM signal applied to the EN pin. The maximum  
frequency for dimming is limited by the start-up time,  
which varies with the LED current. By varying the duty  
cycle of the signal applied on the EN pin (from 0 to  
100%), the LED current is changing linearly.  
The MCP1662 non-synchronous boost LED current  
regulator operates over a wide output range, up to 32V,  
which allows it to drive up to 10 LEDs in series connec-  
tion. The input voltage ranges from 2.4V to 5.5V. The  
device operates down to 1.85V with limited specifica-  
tion. The UVLO typical thresholds are set to 2.3V when  
VIN is ramping and to 1.85V when VIN is falling. Output  
current capability increases with the input voltage and  
is limited by the 1.3A typical peak input current limit.  
Typical characterization curves in this data sheet are  
presented to display the typical output current capabil-  
ity.  
5.2.3  
OUTPUT CURRENT CAPABILITY.  
MINIMUM INPUT VOLTAGE  
The maximum device output current is dependent on  
the input and output voltage. As there is a 1.3A inductor  
peak current limit, output current can go out of regula-  
tion before reaching the maximum duty cycle. (Note  
that, for boost converters, the average inductor current  
is equal to the input current.) Characterization graphs  
show device limits.  
5.2  
LED Brightness Control  
5.2.1  
ADJUSTABLE CONSTANT  
CURRENT CALCULATIONS  
The maximum number of LEDs (nLED in Equation 5-2)  
that can be placed in series and be driven is dependent  
on the maximum LED forward voltage (VFmax) and LED  
current set by the RSET resistor. The voltage at the out-  
put of the MCP1662, plus a margin, should be below  
36V. Consider that VFmax has some variation over the  
operating temperature range and that the LED data  
sheet must be reviewed for the correct data to be intro-  
duced in Equation 5-2. A maximum of 10 white LEDs in  
series connection can be driven safely.  
To calculate the resistor value to set the LED current,  
use Equation 5-1, where RSET is connected to VFB and  
GND. The reference voltage, VFB, is 300 mV. The cal-  
culated current does not depend on the number of  
LEDs in the string.  
EQUATION 5-1:  
VFB  
RSET = -----------  
ILED  
EQUATION 5-2:  
EXAMPLE 1:  
VFmax nLED+ VFB36V  
VFB = 300 mV  
ILED = 25 mA  
RSET = 12  
Characterization graphs show the maximum current  
the device can supply according to the number of LEDs  
at the output.  
For example, to ensure a 100 mA load current for 4  
LEDs (output equal to approximately 12V), a minimum  
of 3.1V input voltage is necessary. If an application  
requires driving 8 LEDs and is powered by one Li-Ion  
battery (VIN from 3.3V to 4.2V), the LED current the  
MCP1662 device can regulate is close to 75 mA  
(Figure 2-6).  
EXAMPLE 2:  
VFB  
ILED  
=
=
=
300 mV  
100 mA  
3  
RSET  
The power dissipated on the RSET resistor is very low  
and equal to VFB x ILED. For ILED = 100 mA, the power  
dissipated on the sense resistor is 30 mW and the effi-  
ciency of the conversion is high.  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 13  
MCP1662  
5.2.4  
OPEN LOAD PROTECTION  
5.4  
Output Capacitor Selection  
The MCP1662 device features an open load protection  
(OLP) in case the LED is disconnected from the output  
line. If the voltage on the VFB pin drops below 50 mV,  
the device stops switching and prevents overvoltage on  
the output and SW pin, and excessive current into  
LEDs.  
The output capacitor helps provide a stable output volt-  
age and smooth load current during sudden load tran-  
sients and reduces the LED current ripple. Ceramic  
capacitors are well suited for this application (X5R and  
X7R). The output capacitor ranges from 4.7 µF in case  
of light loads and static applications, and up to 20 µF  
for hundreds of mA LED current applications.  
OLP is not enabled during start-up and thermal shut-  
down events. Since OLP is not enabled during these  
events, a PWM dimming application on the EN pin  
needs extra overvoltage circuits such as a Zenner  
diode connected in parallel with the LED string.  
As mentioned in Section 5.3, Input Capacitor Selection  
X7R or X5R capacitance varies over the operating tem-  
perature or the DC bias range. With a voltage applied  
at the maximum DC rating, capacitance might drop  
down to half. This might affect the stability or limit the  
output power. Capacitance drop over the entire tem-  
perature range is less than 20%. Users must carefully  
select the DC voltage rating (DCVRATE) for the output  
capacitor according to Equation 5-3 or 5-4:  
5.3  
Input Capacitor Selection  
The boost input current is smoothed by the boost  
inductor, reducing the amount of filtering necessary at  
the input. Some capacitance is recommended to pro-  
vide decoupling from the source and to ensure that the  
input does not drop excessively during switching tran-  
sients. Because MCP1662 is rated to work at an ambi-  
ent temperature of up to 125°C, low ESR X7R ceramic  
capacitors are well suited since they have a low tem-  
perature coefficient and small size. For use within a lim-  
ited temperature range of up to 85°C, an X5R ceramic  
capacitor can be used. For light load applications,  
4.7 µF of capacitance is sufficient at the input. For  
high-power applications that have high source imped-  
ance or long leads, using a 10–20 µF input capacitor is  
recommended. When the device is working below a  
3.0V input with high LED current, additional input  
capacitance can be added to provide a stable input  
voltage (3 x 10 µF or 33 µF) due to high input current  
demand. The input capacitor must be rated at a mini-  
mum of 6.3V. For MLCC ceramic capacitors and X7R  
or X5R capacitors, capacitance varies over the operat-  
ing temperature or the DC bias range. Usually, there is  
a drop down to 50% of capacitance. Review the capac-  
itor manufacturer data sheet to see how rated capaci-  
tance varies over these conditions.  
EQUATION 5-3:  
DCVRATE VFmax nLED+ VFB  
OR  
EQUATION 5-4:  
DCVRATE VOUTmax  
Table 5-1 contains the recommended range for the  
input and output capacitor value.  
TABLE 5-1:  
CAPACITOR VALUE RANGE  
CIN  
COUT  
Minimum  
Maximum  
4.7 µF  
4.7 µF  
47 µF  
Table 5-1 contains the recommended range for the  
input capacitor value.  
DS20005316E-page 14  
2014-2015 Microchip Technology Inc.  
MCP1662  
5.5  
Inductor Selection  
5.6  
Rectifier Diode Selection  
The MCP1662 device is designed to be used with small  
surface mount inductors; the inductance value can  
range from 4.7 µH to 10 µH. An inductance value of  
4.7 µH is recommended for output voltages below 15V  
(4 or 5 LEDs in series connection). For higher output  
voltages, up to 32V (from 5 to a maximum of 10 LEDs),  
an inductance value of 10 µH is optimum.  
Schottky diodes are used to reduce losses. The diode’s  
average current must be higher than the maximum out-  
put current. The diode’s reverse breakdown voltage  
must be higher than the internal switch rating voltage of  
36V.  
The converter’s efficiency will be improved if the volt-  
age drop across the diode is lower. The forward voltage  
(VF) rating is forward-current dependent, which is equal  
in particular to the load current.  
TABLE 5-2:  
MCP1662 RECOMMENDED  
INDUCTORS FOR BOOST  
CONVERTER  
For high currents and high ambient temperatures, use  
a diode with good thermal characteristics.  
Value  
(µH) (typ)  
DCR  
ISAT  
(A)  
Size  
WxLxH (mm)  
Part Number  
TABLE 5-3:  
RECOMMENDED SCHOTTKY  
DIODES  
Coilcraft  
MSS5131-472  
4.7  
4.7  
5.6  
10  
0.038  
0.057  
0.175  
0.065  
0.084  
1.42  
2.7  
1.6  
1.5  
1.9  
5.1x5.1x3.1  
4.2x4.2x2.1  
5.0x5.0x1.5  
6.2x6.2x3.5  
4.3x4.3x4.1  
Type  
VOUTmax  
TA  
XFL4020-472  
PMEG2005  
PMEG4005  
MBR0520  
MBR0540  
18V  
36V  
18V  
36V  
< 85°C  
< 85°C  
< 125°C  
< 125°C  
LPS5015-562  
LPS6235-103  
XAL4040-103  
10  
Würth Elektronik  
744025004 WE-TPC  
744043004 WE-TPC  
744773112 WE-PD2  
74408943100 WE-SPC  
TDK Corporation  
B82462G4472  
4.7  
4.7  
10  
0.1  
1.7  
1.7  
1.6  
2.1  
2.8x2.8x2.8  
4.8x4.8x2.8  
4.0x4.5x3.2  
4.8x4.8x3.8  
0.05  
5.7  
Thermal Calculations  
0.156  
0.082  
10  
The MCP1662 device is available in two different pack-  
ages (5-lead SOT-23 and 8-lead 2x3 TDFN). By calcu-  
lating the power dissipation and applying the package  
thermal resistance (JA), the junction temperature is  
estimated. The maximum continuous junction tempera-  
ture rating for the MCP1662 device is +125°C.  
4.7  
10  
0.04  
0.062  
0.087  
1.8  
1.3  
6.3x6.3x3.0  
6.3x6.3x3.0  
4.0x4.0x2.4  
B82462G4103  
VLCF4024T-4R7  
4.7  
1.43  
Several parameters are used to select the correct  
inductor: maximum rated current, saturation current,  
and direct resistance (DCR). For boost converters, the  
inductor current is much higher than the output current.  
The average inductor current is equal to the input cur-  
rent. The inductor’s peak current is 30-40% higher than  
the average. The lower the inductor DCR, the higher  
the efficiency of the converter: a common trade-off in  
size versus efficiency.  
To quickly estimate the internal power dissipation for  
the switching boost regulator, an empirical calculation  
using measured efficiency can be used. Given the  
measured efficiency, the internal power dissipation is  
estimated by Equation 5-5.  
EQUATION 5-5:  
V
I  
OUT OUT  
------------------------------------- – V  
I  
OUT OUT  
= P  
The saturation current typically specifies a point at  
which the inductance has rolled off a percentage of the  
rated value. This can range from a 20% to 40% reduc-  
tion in inductance. As inductance rolls off, the inductor  
ripple current increases, as does the peak switch cur-  
rent. It is important to keep the inductance from rolling  
off too much, causing switch current to reach the peak  
limit.  
Dis  
Efficiency  
The difference between the first term, input power, and  
the second term, power delivered, is the power dissi-  
pated when using the MCP1662 device. This is an esti-  
mate, assuming that most of the power lost is internal  
to the MCP1662 and not CIN, COUT, the rectifier diode,  
and the inductor. There is some percentage of power  
lost in the boost inductor and the rectifier diode, with  
very little loss in the input and output capacitors. For a  
more accurate estimate of internal power dissipation,  
subtract the IINRMS2 x LDCR and ILED x VF power dissi-  
pation (where IINRMS is the average input current, LDCR  
is the inductor series resistance, and VF is the diode  
voltage drop). Another source of loss for the LED driver  
that is external to the MCP1662 is the sense resistor.  
The losses for the sense resistor can be approximated  
by VFB x ILED  
.
2014-2015 Microchip Technology Inc.  
DS20005316E-page 15  
MCP1662  
The RSET resistor and feedback signal should be  
routed away from the switching node and the switching  
current loop. When possible, ground planes and traces  
should be used to help shield the feedback signal and  
minimize noise and magnetic interferences.  
5.8  
PCB Layout Information  
Good printed circuit board layout techniques are  
important to any switching circuitry, and switching  
power supplies are no different. When wiring the  
switching high-current paths, short and wide traces  
should be used. Therefore it is important that the input  
and output capacitors be placed as close as possible to  
the MCP1662 to minimize the loop area.  
EN  
+VIN  
CIN  
Vias to GND Bottom Plane  
MCP1662  
1
RSET  
GND  
LED1  
LEDN  
L
A
K
LEDs  
A
D
COUT  
K
+VOUT  
GND  
Vias to GND Bottom Plane  
GND Bottom Plane  
FIGURE 5-1:  
MCP1662 5-Lead SOT-23 Recommended Layout.  
+V  
OUT  
A
K
L
D
A
LED1  
+V  
IN  
COUT  
LED2  
LEDN  
K
MCP1662  
CIN  
LEDs  
Via to GND  
RSET  
1
EN  
GND  
GND Bottom Plane  
Vias to GND  
Bottom Plane  
FIGURE 5-2:  
MCP1662 TDFN Recommended Layout.  
DS20005316E-page 16  
2014-2015 Microchip Technology Inc.  
MCP1662  
6.0  
6.1  
PACKAGING INFORMATION  
Package Marking Information  
5-Lead SOT-23  
Example  
AAAM5  
25256  
XXXXY  
8-Lead TDFN (2x3x0.75 mm)  
Example  
ACA  
543  
25  
Legend: XX...X Customer-specific information  
Y
YY  
WW  
NNN  
Year code (last digit of calendar year)  
Year code (last 2 digits of calendar year)  
Week code (week of January 1 is week ‘01’)  
Alphanumeric traceability code  
Pb-free JEDEC® designator for Matte Tin (Sn)  
e
3
*
This package is Pb-free. The Pb-free JEDEC designator (  
can be found on the outer packaging for this package.  
)
e3  
Note: In the event the full Microchip part number cannot be marked on one line, it will  
be carried over to the next line, thus limiting the number of available characters  
for customer-specific information.  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 17  
MCP1662  
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ꢸꢁꢀꢗ  
ꢗꢁꢺꢗ  
ꢗꢁꢷꢗ  
ꢸꢗꢻ  
ꢮꢀ  
ꢗꢁꢗꢷ  
ꢗꢁꢘꢗ  
ꢗꢁꢘꢺ  
ꢗꢁꢟꢀ  
ꢛꢔꢊꢃꢉꢜ  
ꢀꢁ ꢂꢃꢄꢅꢆꢇꢃꢈꢆꢇꢉꢂꢉꢊꢆꢋꢉꢌꢀꢉꢋꢈꢉꢆꢈꢍꢉꢃꢆꢎꢏꢐꢋꢅꢉꢄꢈꢏꢋꢉꢑꢏꢊꢇꢒꢉꢈꢓꢉꢔꢓꢈꢍꢓꢐꢇꢃꢈꢆꢇꢁꢉꢕꢈꢏꢋꢉꢑꢏꢊꢇꢒꢉꢈꢓꢉꢔꢓꢈꢍꢓꢐꢇꢃꢈꢆꢇꢉꢇꢒꢊꢏꢏꢉꢆꢈꢍꢉꢅꢖꢎꢅꢅꢋꢉꢗꢁꢀꢘꢙꢉꢄꢄꢉꢔꢅꢓꢉꢇꢃꢋꢅꢁ  
ꢘꢁ ꢂꢃꢄꢅꢆꢇꢃꢈꢆꢃꢆꢚꢉꢊꢆꢋꢉꢍꢈꢏꢅꢓꢊꢆꢎꢃꢆꢚꢉꢔꢅꢓꢉꢛꢜꢕꢌꢉꢝꢀꢞꢁꢟꢕꢁ  
ꢠꢜꢡꢢ ꢠꢊꢇꢃꢎꢉꢂꢃꢄꢅꢆꢇꢃꢈꢆꢁꢉꢣꢒꢅꢈꢓꢅꢍꢃꢎꢊꢏꢏꢤꢉꢅꢖꢊꢎꢍꢉꢥꢊꢏꢐꢅꢉꢇꢒꢈꢦꢆꢉꢦꢃꢍꢒꢈꢐꢍꢉꢍꢈꢏꢅꢓꢊꢆꢎꢅꢇꢁ  
ꢕꢃꢎꢓꢈꢎꢒꢃꢔ ꢎꢒꢆꢈꢏꢈꢚꢤ ꢂꢓꢊꢦꢃꢆꢚ ꢡꢗꢞꢼꢗꢴꢀꢠ  
DS20005316E-page 18  
2014-2015 Microchip Technology Inc.  
MCP1662  
Note: For the most current package drawings, please see the Microchip Packaging Specification located at  
http://www.microchip.com/packaging  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 19  
MCP1662  
Note: For the most current package drawings, please see the Microchip Packaging Specification located at  
http://www.microchip.com/packaging  
DS20005316E-page 20  
2014-2015 Microchip Technology Inc.  
MCP1662  
Note: For the most current package drawings, please see the Microchip Packaging Specification located at  
http://www.microchip.com/packaging  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 21  
MCP1662  
ꢝꢁꢂꢃꢄꢅꢆꢇꢈꢄꢉꢊꢋꢌꢆꢞꢐꢄꢈꢆꢟꢈꢄꢊꢠꢆꢛꢔꢆꢂꢃꢄꢅꢆꢇꢄꢌꢡꢄꢢꢃꢆꢕꢣꢛꢖꢆꢤꢆꢘꢥꢙꢥꢦꢧꢨꢀꢆꢎꢎꢆꢩꢔꢅꢪꢆꢗꢒꢞꢟꢛꢚ  
ꢛꢔꢊꢃꢜ ꢧꢈꢓꢉꢍꢒꢅꢉꢄꢈꢇꢍꢉꢎꢐꢓꢓꢅꢆꢍꢉꢔꢊꢎꢨꢊꢚꢅꢉꢋꢓꢊꢦꢃꢆꢚꢇꢩꢉꢔꢏꢅꢊꢇꢅꢉꢇꢅꢅꢉꢍꢒꢅꢉꢕꢃꢎꢓꢈꢎꢒꢃꢔꢉꢪꢊꢎꢨꢊꢚꢃꢆꢚꢉꢜꢔꢅꢎꢃꢑꢃꢎꢊꢍꢃꢈꢆꢉꢏꢈꢎꢊꢍꢅꢋꢉꢊꢍꢉ  
ꢒꢍꢍꢔꢢꢫꢫꢦꢦꢦꢁꢄꢃꢎꢓꢈꢎꢒꢃꢔꢁꢎꢈꢄꢫꢔꢊꢎꢨꢊꢚꢃꢆꢚ  
DS20005316E-page 22  
2014-2015 Microchip Technology Inc.  
MCP1662  
APPENDIX A: REVISION HISTORY  
Revision E (September 2015)  
• The following is the list of modifications:  
• Updated Features and General Description sec-  
tions.  
• Updated parameters in the DC and AC Character-  
istics table.  
• Updated Figures 2-10, 2-11 and 2-12.  
• Corrected Section 4.2.2 “Start-up”.  
• Minor updates in Section 4.2.6 “Internal Com-  
pensation” and Section 4.2.9 “Output Short  
Circuit Condition”.  
• Corrected Figure 5-1.  
Revision D (March 2015)  
The following is the list of modifications  
Updated the example packages in Section 6.0  
“Packaging Information”.  
Revision C (December 2014)  
The following is the list of modifications:  
Updated the example packages in Section 6.0  
“Packaging Information”.  
Revision B (November 2014)  
The following is the list of modifications:  
• Updated the example packages in Section 6.0  
“Packaging Information”  
• Minor typographical corrections.  
Revision A (June 2014)  
• Original Release of this Document.  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 23  
MCP1662  
NOTES:  
DS20005316E-page 24  
2014-2015 Microchip Technology Inc.  
MCP1662  
PRODUCT IDENTIFICATION SYSTEM  
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.  
(1)  
X
/XX  
[X]  
Examples:  
PART NO.  
Device  
a)  
MCP1662T-E/MNY: Tape and Reel,  
Temperature Package  
Range  
Tape and Reel  
Option  
Extended temperature,  
8LD TFDN package  
Tape and Reel,  
b)  
MCP1662T-E/OT:  
Extended temperature,  
5LD SOT-23 package  
Device:  
MCP1662: High-Voltage Step-Up LED Driver with UVLO and  
OLP  
Tape and Reel  
Option:  
T
E
= Tape and Reel(1)  
Temperature  
Range:  
= -40C to +125C (Extended)  
Note 1:  
Tape and Reel identifier only appears in the  
catalog part number description. This  
identifier is used for ordering purposes and  
is not printed on the device package. Check  
with your Microchip Sales Office for package  
availability with the Tape and Reel option.  
Package:  
MN* = Plastic Dual Flat, No Lead – 2x3x0.75 mm Body  
(TDFN)  
OT  
*Y  
=
=
Plastic Small Outline Transistor (SOT-23)  
Nickel palladium gold manufacturing designator.  
Only available on the TDFN package.  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 25  
MCP1662  
NOTES:  
DS20005316E-page 26  
2014-2015 Microchip Technology Inc.  
Note the following details of the code protection feature on Microchip devices:  
Microchip products meet the specification contained in their particular Microchip Data Sheet.  
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the  
intended manner and under normal conditions.  
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our  
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data  
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.  
Microchip is willing to work with the customer who is concerned about the integrity of their code.  
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not  
mean that we are guaranteeing the product as “unbreakable.”  
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our  
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts  
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.  
Information contained in this publication regarding device  
applications and the like is provided only for your convenience  
and may be superseded by updates. It is your responsibility to  
ensure that your application meets with your specifications.  
MICROCHIP MAKES NO REPRESENTATIONS OR  
WARRANTIES OF ANY KIND WHETHER EXPRESS OR  
IMPLIED, WRITTEN OR ORAL, STATUTORY OR  
OTHERWISE, RELATED TO THE INFORMATION,  
INCLUDING BUT NOT LIMITED TO ITS CONDITION,  
QUALITY, PERFORMANCE, MERCHANTABILITY OR  
FITNESS FOR PURPOSE. Microchip disclaims all liability  
arising from this information and its use. Use of Microchip  
devices in life support and/or safety applications is entirely at  
the buyer’s risk, and the buyer agrees to defend, indemnify and  
hold harmless Microchip from any and all damages, claims,  
suits, or expenses resulting from such use. No licenses are  
conveyed, implicitly or otherwise, under any Microchip  
intellectual property rights unless otherwise stated.  
Trademarks  
The Microchip name and logo, the Microchip logo, dsPIC,  
FlashFlex, flexPWR, JukeBlox, KEELOQ, KEELOQ logo, Kleer,  
LANCheck, MediaLB, MOST, MOST logo, MPLAB,  
32  
OptoLyzer, PIC, PICSTART, PIC logo, RightTouch, SpyNIC,  
SST, SST Logo, SuperFlash and UNI/O are registered  
trademarks of Microchip Technology Incorporated in the  
U.S.A. and other countries.  
The Embedded Control Solutions Company and mTouch are  
registered trademarks of Microchip Technology Incorporated  
in the U.S.A.  
Analog-for-the-Digital Age, BodyCom, chipKIT, chipKIT logo,  
CodeGuard, dsPICDEM, dsPICDEM.net, ECAN, In-Circuit  
Serial Programming, ICSP, Inter-Chip Connectivity, KleerNet,  
KleerNet logo, MiWi, motorBench, MPASM, MPF, MPLAB  
Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach,  
Omniscient Code Generation, PICDEM, PICDEM.net, PICkit,  
PICtail, RightTouch logo, REAL ICE, SQI, Serial Quad I/O,  
Total Endurance, TSHARC, USBCheck, VariSense,  
ViewSpan, WiperLock, Wireless DNA, and ZENA are  
trademarks of Microchip Technology Incorporated in the  
U.S.A. and other countries.  
SQTP is a service mark of Microchip Technology Incorporated  
in the U.S.A.  
Silicon Storage Technology is a registered trademark of  
Microchip Technology Inc. in other countries.  
GestIC is a registered trademark of Microchip Technology  
Germany II GmbH & Co. KG, a subsidiary of Microchip  
Technology Inc., in other countries.  
All other trademarks mentioned herein are property of their  
respective companies.  
© 2014-2015, Microchip Technology Incorporated, Printed in  
the U.S.A., All Rights Reserved.  
ISBN: 978-1-63277-776-8  
QUALITY MANAGEMENT SYSTEM  
CERTIFIED BY DNV  
Microchip received ISO/TS-16949:2009 certification for its worldwide  
headquarters, design and wafer fabrication facilities in Chandler and  
Tempe, Arizona; Gresham, Oregon and design centers in California  
and India. The Company’s quality system processes and procedures  
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping  
devices, Serial EEPROMs, microperipherals, nonvolatile memory and  
analog products. In addition, Microchip’s quality system for the design  
and manufacture of development systems is ISO 9001:2000 certified.  
== ISO/TS 16949 ==  
2014-2015 Microchip Technology Inc.  
DS20005316E-page 27  
Worldwide Sales and Service  
AMERICAS  
ASIA/PACIFIC  
ASIA/PACIFIC  
EUROPE  
Corporate Office  
2355 West Chandler Blvd.  
Chandler, AZ 85224-6199  
Tel: 480-792-7200  
Fax: 480-792-7277  
Technical Support:  
http://www.microchip.com/  
support  
Asia Pacific Office  
China - Xiamen  
Tel: 86-592-2388138  
Fax: 86-592-2388130  
Austria - Wels  
Tel: 43-7242-2244-39  
Fax: 43-7242-2244-393  
Suites 3707-14, 37th Floor  
Tower 6, The Gateway  
Harbour City, Kowloon  
China - Zhuhai  
Tel: 86-756-3210040  
Fax: 86-756-3210049  
Denmark - Copenhagen  
Tel: 45-4450-2828  
Fax: 45-4485-2829  
Hong Kong  
Tel: 852-2943-5100  
Fax: 852-2401-3431  
India - Bangalore  
Tel: 91-80-3090-4444  
Fax: 91-80-3090-4123  
France - Paris  
Tel: 33-1-69-53-63-20  
Fax: 33-1-69-30-90-79  
Australia - Sydney  
Tel: 61-2-9868-6733  
Fax: 61-2-9868-6755  
Web Address:  
www.microchip.com  
India - New Delhi  
Tel: 91-11-4160-8631  
Fax: 91-11-4160-8632  
Germany - Dusseldorf  
Tel: 49-2129-3766400  
Atlanta  
Duluth, GA  
Tel: 678-957-9614  
Fax: 678-957-1455  
China - Beijing  
Tel: 86-10-8569-7000  
Fax: 86-10-8528-2104  
Germany - Karlsruhe  
Tel: 49-721-625370  
India - Pune  
Tel: 91-20-3019-1500  
China - Chengdu  
Tel: 86-28-8665-5511  
Fax: 86-28-8665-7889  
Germany - Munich  
Tel: 49-89-627-144-0  
Fax: 49-89-627-144-44  
Austin, TX  
Tel: 512-257-3370  
Japan - Osaka  
Tel: 81-6-6152-7160  
Fax: 81-6-6152-9310  
Boston  
China - Chongqing  
Tel: 86-23-8980-9588  
Fax: 86-23-8980-9500  
Italy - Milan  
Tel: 39-0331-742611  
Fax: 39-0331-466781  
Westborough, MA  
Tel: 774-760-0087  
Fax: 774-760-0088  
Japan - Tokyo  
Tel: 81-3-6880- 3770  
Fax: 81-3-6880-3771  
China - Dongguan  
Tel: 86-769-8702-9880  
Italy - Venice  
Tel: 39-049-7625286  
Chicago  
Itasca, IL  
Tel: 630-285-0071  
Fax: 630-285-0075  
Korea - Daegu  
Tel: 82-53-744-4301  
Fax: 82-53-744-4302  
China - Hangzhou  
Tel: 86-571-8792-8115  
Fax: 86-571-8792-8116  
Netherlands - Drunen  
Tel: 31-416-690399  
Fax: 31-416-690340  
Korea - Seoul  
Cleveland  
Tel: 82-2-554-7200  
Fax: 82-2-558-5932 or  
82-2-558-5934  
China - Hong Kong SAR  
Tel: 852-2943-5100  
Fax: 852-2401-3431  
Poland - Warsaw  
Tel: 48-22-3325737  
Independence, OH  
Tel: 216-447-0464  
Fax: 216-447-0643  
Spain - Madrid  
Tel: 34-91-708-08-90  
Fax: 34-91-708-08-91  
China - Nanjing  
Tel: 86-25-8473-2460  
Fax: 86-25-8473-2470  
Malaysia - Kuala Lumpur  
Tel: 60-3-6201-9857  
Fax: 60-3-6201-9859  
Dallas  
Addison, TX  
Tel: 972-818-7423  
Fax: 972-818-2924  
Sweden - Stockholm  
Tel: 46-8-5090-4654  
China - Qingdao  
Tel: 86-532-8502-7355  
Fax: 86-532-8502-7205  
Malaysia - Penang  
Tel: 60-4-227-8870  
Fax: 60-4-227-4068  
Detroit  
Novi, MI  
UK - Wokingham  
Tel: 44-118-921-5800  
China - Shanghai  
Tel: 86-21-5407-5533  
Fax: 86-21-5407-5066  
Philippines - Manila  
Tel: 63-2-634-9065  
Fax: 63-2-634-9069  
Tel: 248-848-4000  
Fax: 44-118-921-5820  
Houston, TX  
Tel: 281-894-5983  
China - Shenyang  
Tel: 86-24-2334-2829  
Fax: 86-24-2334-2393  
Singapore  
Tel: 65-6334-8870  
Fax: 65-6334-8850  
Indianapolis  
Noblesville, IN  
Tel: 317-773-8323  
Fax: 317-773-5453  
China - Shenzhen  
Tel: 86-755-8864-2200  
Fax: 86-755-8203-1760  
Taiwan - Hsin Chu  
Tel: 886-3-5778-366  
Fax: 886-3-5770-955  
Los Angeles  
Mission Viejo, CA  
Tel: 949-462-9523  
Fax: 949-462-9608  
China - Wuhan  
Tel: 86-27-5980-5300  
Fax: 86-27-5980-5118  
Taiwan - Kaohsiung  
Tel: 886-7-213-7828  
Taiwan - Taipei  
Tel: 886-2-2508-8600  
Fax: 886-2-2508-0102  
New York, NY  
Tel: 631-435-6000  
China - Xian  
Tel: 86-29-8833-7252  
Fax: 86-29-8833-7256  
San Jose, CA  
Tel: 408-735-9110  
Thailand - Bangkok  
Tel: 66-2-694-1351  
Fax: 66-2-694-1350  
Canada - Toronto  
Tel: 905-673-0699  
Fax: 905-673-6509  
07/14/15  
DS20005316E-page 28  
2014-2015 Microchip Technology Inc.  

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