Datasheet LED Drivers for LCD Backlights 6ch boost LED driver which constant setting can be shared by I2C control BD9423EFV 1.1 General Description Key Specifications BD9423EFV is a high efficiency driver for white LEDs LED drivers Max curret 400mA per channel and designed for large LCD panel. This IC is built-in high Constant current accuracy 1.8% (IC only) current drive and high responsibility type 6ch LED Current analog (linear) dimming by ADIM pin drivers and 1ch boost DCDC converter. BD9423EFV has Several protection functions some protect function against fault conditions, such as DCDC part : OCP/OVP/UVLO the over-voltage protection (OVP), LED OPEN and LED driver part :OPEN,SHORT detection SHORT protection, the over current limit protection of SHORT detection voltage is set by LSP pin DCDC (OCP). Therefore BD9423EFV is available for the Error detection output by FAIL pin fail-safe design over a wide range output voltage. Master/Slave mode inside Moreover the functions and the detection voltage can be controlled by the I2C. This enables for the constant 1.2 Package W(Typ) x D(Typ) x H(Max) setting of external parts to be shared by I2C control, HTSSOP-B40: 13.60mm x 7.80mm x 1.00mm nevertheless the different usage condition. Pin Pitch: 0.65mm Features Operating power supply voltage range:9.0V to 35.0V Oscillator frequency: 200kHz (RT=100k) Operating Current: 9mA (typ.) Operating temperature range: -40C to +85C Applications TV, Computer Display, Notebook, LCD Backlighting Figure 1. HTSSOP-B40 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 TSZ02201-0F2F0C100080-1-2 2014 ROHM Co., Ltd. All rights reserved. 1/57 TSZ22111 14 001 9.Oct.2015 Rev.001DatasheetDatasheet BD9423EFV 1.3 Pin Configuration Figure 3. Pin Configuration 1.4 Pin Descriptions No. Name Function No. Name Function 1 VCC Power supply pin 40 AGND GND pin for analog part Low voltage malfunction 2 FAIL Abnormality detection output pin 39 UVLO detection pin LED SHORT detection voltage 3 REG9V 9.0V regulator output pin 38 LSP setting pin LED feedback voltage setting 4 - 37 N.C. LED LV pin Pulse analog dimming signal 5 DC/DC switching output pin 36 N ADIM P input pin Analog dimming DC voltage I/O 6 Power GND pin 35 PGND ADIM pin Connecting pin for DC/DC 7 CS DC/DC FET current detection pin 34 RT frequency setting resistor 8 OVP OVP detection pin 33 FB Error AMP output pin 9 FAIL function selection pin 32 Connecting pin for soft start FAIL MODE SS 10 AGND GND pin for analog part 31 CP setting capacitor 11 LED1 LED output 1 30 S1 Connecting pin for abnormality 12 LED output 2 29 detection setting capacitor LED2 S2 Connecting pin for LED1 constant 13 LED output 3 28 LED3 S3 current setting resistor Connecting pin for LED2 constant 14 LED output 4 27 LED4 S4 current setting resistor Connecting pin for LED3 constant 15 LED output 5 26 LED5 S5 current setting resistor Connecting pin for LED4 constant 16 LED6 LED output 6 25 S6 current setting resistor Connecting pin for LED5 constant 17 STB ON/OFF pin 24 FAIL RST current setting resistor Power supply pin for I2C part Connecting pin for LED6 constant 18 23 DVDD SUMPWM and register current setting resistor 19 SDA I2C data pin 22 DGND FAIL output reset pin Master/Slave setting input/output 20 SCL I2C Clock pin 21 PWM pin www.rohm.com TSZ02201-0F2F0C100080-1-2 2014 ROHM Co., Ltd. All rights reserved. 2/57 TSZ22111 15 001 9.Oct.2015 Rev.001