G2541 Global Mixed-mode Technology 6-Channels 40V White LED Driver with Boost Regulator Features General Description The G2541 is a high-efficiency 6-channel white LED driver. It is designed for LCD panel that employs an LED array as the lighting source. An integrated switch current mode boost controller drives six strings in parallel and supports up to 10 pieces of LEDs per string. Wide 4.2V to 24V Input Supply Range 600KHz Fixed Frequency 40V/2A, 0.2Ω n-channel MOSFET Maximum Programmable LED Channel Current 30mA Current accuracy ±3% and current balance ±2% 100Hz~25kHz PWM Dimming PWM to DC Dimming Protection Input Under-Voltage Protection Over Current Protection Over Voltage Protection Thermal Protection RoHs Compliant TQFN4X4-20 Package The G2541 automatically regulated supply voltage for the LED light bars without the need to calculate the output for different LED types. It also integrates a 40V n-channel MOSFET that provides high output power. The 6-channel current driver is ideal for constant current driving, and well matched less than 3%. To set the maximum driving current, the ISET pin is used to determine reference current. Each channel of the current drivers is set to 800 times of this reference current. A PWM pin can be used to perform PWM dimming from the range of 100Hz to 25kHz. The MODE pin in G2541 is used to set the dimming mode. If MODE pin set to floating, the dimming mode is in the PWM mode, the current driver ON/OFF is synchronized with the PWM signal. If Mode pin set to AGND, PWM and ILED current is set at PWM duty multiplied by ISET current when PWM duty ≥ 25%. If the PWM duty <25%, the ILED current is fixed at 0.25xISET, and the dimming duty is 4 x PWM duty. If MODE set to VDC, the dimming mode operated in the Pure DC mode, the current-source outputs are DC dimming and the PWM duty cycle modulates the amplitude of the currents. Open LED-string automatically disable the channel from entering over voltage protection. Applications UMPC and Notebook Computer Backlight Ordering Information ORDER NUMBER TEMP. RANGE G2541R91U 2541 PACKAGE (Green) PACKING -40°C to +85°C TQFN4X4-20 Note:R9: TQFN4X4-20 1: Bonding Code U: Tape & Reel Pin Configuration Typical Application Circuit L1 D1 CVIN LX LX OVP RVIN VCC CVCC VDC 15 LX NC 2 14 PGND MODE ISET 3 13 PGND PWM MODE 4 12 OVP AGND 5 11 CS1 EN G2541 COMP 10 LED3 ISET RISET TQFN4X4-20 LED1 LED2 CC1 CS2 CS3 9 8 CS4 7 6 RC1 CC2 CS5 COUT ROVP1 1 Thermal Pad ROVP2 40V MAX VIN EN CS6 VOUT VIN 16 VDC PWM 17 VIN 19 18 20 COMP G2541 LED4 LED5 LED6 AGND PGND Note: Recommend connecting the Thermal Pad to the Ground for excellent power dissipation. TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 0.2 Aug 12, 2013 1