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GM19371
BOOST WHITE LED DRIVER
WITH OVP
Description
The GM19371 is a step up DC/DC convert
specifically designed to drive white LED;s with a
constant current. The device can drive up to 27
LEDs from a 5V supply.
Additional feature includes output voltage limiting
when LEDs are disconnected.
GM19371 is available in SOT-26 package.
Features
Inherently matched LED current
Drives up to 126LEDs (9S14P) from a
12V supply
36V rugged bipolar switch
Fast 1.2MHz switching frequency
Over Voltage Protection, 30V
Application
Cellular phones
PDAs, Handheld Computers
Digital Cameras
Typical Application Circuits
MP3 Player
GPS Receivers
MR16 Lighting
VIN
6V to 18V
DIM
10µH
D1
C1
4.7µF
61
VIN SW
OVP 5
GM19371
4 CTRL
GND
2
FB 3
14 Strings in Parallel
9 LED in Series
RSET 20mA x 14
Figure 1 GM19371 typical application
C2
4.7µF
www.gammamicro.com.tw 1
Free Datasheet http://www.datasheet4u.com/
GM19371
BOOST WHITE LED DRIVER
WITH OVP
Marking Information and Pin Configurations (Top View)
SOT26
VIN OVP CTRL
6 54
70YWW
123
SW GND FB
70: Device Code, Green Product
Y: Year
WW: Week code
Pin Descriptions
Pin Number
Pin Name
1 SW
2 GND
3 FB
4 CTRL
5 OVP
6 VIN
Pin Function
This is the collector of the internal NPN power switch.
Connect to inductor and diode. Minimize the metal trace area
connected to this pin to reduce EMI.
Ground
Reference voltage is 95mV. Connect LEDs and a resistor at this pin.
LED current is determined by the resistance and CTRL voltage. RSET
resistor value is calculated as RSET = 95mV/ILED
This Pin could be used as either shut down or dimming functions:
When VCTRL > 1.8V, generates full scale LED current
VCTRL < 0.4V, chip is OFF
0.4V ≤ VCTRL ≤ 1.8V, PWM duty cycle controls the LED current
Over Voltage Protection, 30V
The input supply pin, bypass this pin with a capacitor as close to the
device as possible
Ordering Information – Green Products
Ordering Number
GM19371-ST26RG
Package
SOT-26
Shipping
3,000 Units/Tape and Reel
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