REG75 VCC N PGND AGND CS FAIL OVP RT FB VREF STB STB VREF BSx CLx PWM PWM Datasheet LED Drivers for LCD Backlights White LED Driver for large LCD Panels (DCDC Converter Type) BD9421F General Description Key Specifications BD9421F is high efficiency driver for white LED. This is VCC Supply Voltage Range: 9.0V to 35.0V designed for large sized LCD. BD9421F is built-in DCDC Oscillation Frequency: 150kHz(RT=100k ) DCDC converters that supply appropriate voltage for Operation Circuit Current: 5mA(Typ) light source. Operating Temperature Range: -40C to +85C BD9421F is also built-in protection function for abnormal state such as OVP: over voltage protection, OCP: over current limit protection of DCDC, SCP: short Applications circuit protection, open detection of LED string. LED driver for TV, Monitor and LCD Back Light Thus this is used for conditions of large output voltage and load conditions. Package W(Typ) x D(Typ) x H(Max) SOP24 15.00mm x 7.80mm x 2.01mm Features Pin Pitch 1.27mm 6ch LED constant current driver(External PNP Tr Type) Maximum LED setting current 500mA(VREF Pin setting) 2% LED current accuracy(VREF=0.9V setting) Built-in DC/DC converter Analog Dimming(Linear) function LED protection function(OPEN/SHORT protection) PWM-independent Type Individual detection and individual LED OFF for both OPEN and SHORT circuit VOUT Over Voltage Protection(OVP) and reduced voltage protection(SCP) circuit Built-in under voltage lockout function(UVLO) and Figure 1. SOP24 over voltage protection(OVP) Built-in VOUT discharge circuit while shutdown 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 TSZ02201-0F1F0C100310-1-2 2013 ROHM Co., Ltd. All rights reserved. 1/27 TSZ22111 14 001 25.Sep.2015 Rev.003DatasheetDatasheet BD9421F Absolute Maximum Ratings(Ta = 25C) Parameter Symbol Rating Unit Supply Voltage VCC -0.3 to +36 V STB,OVP Voltage STB,OVP -0.3 to +36 V BS1-6 Voltage BS1-6 -0.3 to +60 V CS,CL1-6,FB,RT Voltage CS,CL1-6,FB,RT -0.3 to +7 V REG75,N Voltage REG75,N -0.3 to +14 V PWM,VREF Voltage PWM,VREF -0.3 to +20 V (Note 1) Power Dissipation for SOP24 Pd 0.68 W Operating Temperature Range Topr -40 to +85 C Storage Temperature Range Tstg -55 to +150 C Maximum Junction Temperature Tjmax 150 C (Note 1) Derating in done 5.5mW/C for operating above Ta25C (Mount on 1-layer 70.0mm x 70.0mm x 1.6mm board) Caution: Operating the IC over the absolute maximum ratings may damage the IC. The damage can either be a short circuit between pins or an open circuit between pins and the internal circuitry. Therefore, it is important to consider circuit protection measures, such as adding a fuse, in case the IC is operated over the absolute maximum ratings. Recommended Operating Conditions(Ta= -40C to +85C) Parameter SymbolMin Typ Max Unit Supply Voltage VCC 9 24 35 V DC/DC Oscillation Frequency FSW 100 - 800 kHz Analog Dimming Setting Input Range VREF 0.6 0.9 3.0 V External Component Recommended Range Parameter Symbol Specification Unit VCC pin connecting capacity CVCC 1 to 100 uF REG75 pin connecting capacity C REG 1.0 to 10 uF RT pin connection resistance range RRT 18.75 to 150 k The operating conditions listed above are constants for the IC alone. To make constant setting with practical set devices, utmost attention should be paid. Pin Configuration Marking Diagram and Physical Dimension (TOP VIEW) BD9421F 1PIN MARK LOT No. SOP24 Figure 3. Pin Configuration Figure 4. Physical Dimension www.rohm.com TSZ02201-0F1F0C100310-1-2 2013 ROHM Co., Ltd. All rights reserved. 2/27 TSZ22111 15 001 25.Sep.2015 Rev.003