G5126 Global Mixed-mode Technology High Efficiency, Constant Current, Boost DC/DC White-LEDs Drive Features General Description The G5126 boost converter contains a 0.7Ω internal switch. The IC operates at constant frequency 1MHz, allowing the use of tiny, low cost and low height inductors and capacitors. The IC operates from a 2.7V to 5.5V supply voltage. High inrush current at start-up is eliminated using the soft-start function. Constant frequency current mode PWM architecture results in low, predictable output noise. The G5126 includes cycle-by-cycle 850mA current limiting to maximum inductor current and over-temperature protection circuit. The over-voltage protection will be enabled when VOUT exceeds 28V. The current of LED is set by a resistor connected between FB and GND. The G5126 is available in SOT-23-6 & TDFN2X2-8 package. Operating Voltage：2.7V to 5.5V High Operating Frequency：1MHz High Output Voltage：28V Shutdown Current：<1µA Over-Voltage Protection Digital Dimming Control Built-in Cycle-by-Cycle Current-Limiting Soft-Start Function 0.2V Low Reference Voltage SOT-23-6 & TDFN2X2-8 Package Applications LED Module Compact Back Light Module Constant Current Source Ordering Information ORDER NUMBER MARKING TEMP. RANGE PACKAGE (Green) G5126TB1U 5126x -40°C to 85°C SOT-23-6 G5126RC1U 5126 -40°C to 85°C TDFN2X2-8 Note: TB: SOT-23-6 RC: TDFN2X2-8 1 : Bonding Code U: Tape & Reel Pin Configuration Typical Application Circuit 10µH G5126 LX 1 6 IN GND 2 5 OVP FB 3 G963 4 SOT-23-6 VIN=2.7V to 5.5V G5126 EN VCC 1 NC 2 OVP 3 EN 4 Thermal Pad 8 LX 7 PGND 6 VSS 5 FB CIN 4.7µF COUT 1µF LX IN OVP G5126 FB EN PWM Dimming GND I=20mA TDFN2X2-8 10 R1 Note: Recommend connecting the Thermal Pad to the Ground for excellent power dissipation. TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 0.7 Mar 01, 2013 1