BM531Q11-Z ROHM

Datasheet LED Drivers for LCD Backlights 1ch Buck Type (Quasi-Resonant Control) White LED Driver for Large LCD Included 250V MOSFET BM531Q11 1.1 General Description Key Specifications BM531Q11 is a high efficiency driver for white LEDs and Operating power supply voltage range: designed for large LCDs. BM531Q11 is built-in a VCC: 9.0V to 35.0V quasi-resonant control method DCDC converter that DRAIN: to 250V employ an array of LEDs as the light source. BM531Q11 Operating current: 700 A(typ.) is built-in 250V MOSFET and owing to the external Maximum frequency: 400kHz(typ.) current setting resistance, a power supply design with a Operating temperature range: - 40C to +105C high degree of freedom can be achieved. Features 1.2 Package W(Typ) x D(Typ) x H(Max) Quasi-resonant switching mode DIP7AK 9.20mm6.35mm4.30mm Built-in 250V MOSFET Maximum frequency 400kHz VCC pin: under voltage protection SOURCE pin: Leading-Edge-Blanking function PWM and ADIM dimming operating FAIL signal output (ADIM pin) Applications TV, Computer Display Other LCD backlighting Figure 1. DIP7AK Typical Application Circuit Figure 2. Typical Application Circuit Product structure : Silicon monolithic integrated circuit This product has no designed protection against radioactive rays www.rohm.com TSZ02201-0F4F0C100170-1-2 2016 ROHM Co., Ltd. All rights reserved. 1/20 22.Jul.2016 Rev.001 TSZ2211114 001 DatasheetDatasheet BM531Q11 1.3 Pin Configuration 1 7 SOURCE DRAIN 2 ADIM 3 GND VCC 6 4 ZT PWM 5 Figure 3. Pin Configuration 1.4 Pin Descriptions Pin No. Pin Name Function 1 SOURCE Inductor current sensing pin 2 ADIM Analog dimming signal input and error detection output pin 3 GND - 4 ZT Zero current detection pin 5 PWM PWM signal input pin 6 VCC Power supply pin 7 DRAIN MOSFET DRAIN pin 1. 5 Block Diagram VIN LED+ CIN COUT LED- L VCC VCC UVLO Comp. + SYSTEM ON - 7.5V/6.75V DRAIN 1 shot Reset prior ZT Comp. S Q OUT ZT 10k AND TimeOut OR - AND + 45usec DRIVER OUT R 400kHz 100mV Clamper /200mV VCC Current Limit MAX ON Time Comp. 3k 60us ADIM DC x0.7 - AND Leading Edge 10k OR + Blanking OUT(L->H)0.25us SOURCE Rs PWM + CS OVP - Comp. 300k 50k SOURCE Low DET. + AND Auto Restart - 1.5V/0.8V LOGIC 4.0V/3.8V GND VCC FAILB Figure 4. Block Diagram www.rohm.com TSZ02201-0F4F0C100170-1-2 2016 ROHM Co., Ltd. All rights reserved. 2/20 22.Jul.2016 Rev.001 TSZ22111 15 001