LED Drivers for LCD Backlights 1ch Boost up Type White LED Driver for large LCD BD9411F General Description Key Specifications BD9411F is a high efficiency driver for white LEDs and is Operating power supply voltage range: 9.0V to 35.0V designed for large LCDs. BD9411F has a boost DCDC Oscillator frequency of DCDC: 150kHz (RT=100k) converter that employs an array of LEDs as the light Operating Current: 3.3 mA(Typ) source. Operating temperature range: -40C to +105C BD9411F has some protect functions against fault conditions, such as over-voltage protection (OVP), over current limit protection of DCDC (OCP), LED OCP Package(s) W(Typ) x D(Typ) x H(Max) protection, and over-boost protection (FBMAX). SOP18 11.20mm x 7.80mm x 2.01mm Therefore it is available for the fail-safe design over a Pin pitch 1.27mm wide range output voltage. Features DCDC converter with current mode LED protection circuit (Over boost protection, LED OCP protection) Over-voltage protection (OVP) for the output voltage VOUT Adjustable soft start Adjustable oscillation frequency of DCDC Wide range of analog dimming 0.2V to 3.0V UVLO detection for the input voltage of the power stage LED Dimming PWM Over Duty Protection(ODP) Figure 1. SOP18 Applications TV, Computer Display, LCD Backlighting Typical Application Circuit V OUT V V CC IN VCC UVLO OVP REG90 STB GATE RT CS SS FAIL DIMOUT PWM ADIM ISENSE DUTYP FB Rs DUTYON GND Figure 2. Typical Application Circuit Product structureSilicon monolithic integrated circuit This product has not designed protection against radioactive rays . www.rohm.com TSZ02201-0T2T0C100250-1-2 2017 ROHM Co., Ltd. All rights reserved. 1/34 TSZ2211114001 20.Feb.2017 Rev.001 BD9411F Pin Configuration(s) 1 18 VCC REG 90 2 STB 17 CS 3 OVP 16 GATE 4 UVLO 15 DIMOUT 5 14 SS GND 6 13 DUTYON ISENSE 7 12 PWM FB 8 11 FAIL DUTYP 9 10 ADIM RT Figure 3. Pin Configuration Pin Description(s) Terminal No. Function Name 1 VCC Power supply pin 2 STB IC ON/OFF pin 3 OVP Over voltage protection detection pin 4 UVLO Under voltage lock out detection pin 5 SS Soft start setting pin 6 DUTYON Over Duty Protection ON/OFF pin 7 PWM External PWM dimming signal input pin 8 FAIL Error detection output pin 9 ADIM ADIM signal input pin 10 RT DC/DC switching frequency setting pin 11 DUTYP Over Duty Protection setting pin 12 FB Error amplifier output pin 13 ISENSE LED current detection input pin 14 GND - 15 DIMOUT Dimming signal output for NMOS 16 GATE DC/DC switching output pin DC/DC output current detect pin, 17 CS OCP input pin 18 REG90 9.0V output voltage pin www.rohm.com TSZ02201-0T2T0C100250-1-2 2017 ROHM Co., Ltd. All rights reserved. 2/34 TSZ2211115001 20.Feb.2017 Rev.001