Document
Datasheet
4ch White LED Driver Built-in Current Driver Buck-Boost and Boost DC/DC Converter for Automotive
BD81A44EFV-M BD81A44MUV-M
General Description
Key Specifications
BD81A44EFV-M / BD81A44MUV-M is a white LED driver with the capability of withstanding high input voltage (maximum 35 V). This driver has 4ch constantcurrent drivers in 1-chip, where each channel can draw up to 120 mA (Max), and it is suitable for high illumination LED drive. Furthermore, a buck-boost current mode DC/DC converter is also built to achieve stable operation during power voltage fluctuation. Light modulation (10,000:1@100 Hz dimming function) is possible by PWM input.
Features
◼ Operating Input Voltage Range
4.5 V to 35 V
◼ Output LED Current Accuracy
±3.0 %@50 mA
◼ DC/DC Oscillation Frequency 200 kHz to 2200 kHz
◼ Operating Temperature
-40 °C to +125 °C
◼ LED Maximum Output Current
120 mA/ch
◼ LED Maximum Dimming Ratio 10,000:1@100 Hz
◼ PWM Minimum Pulse Width
1.0 µs
Packages VQFN28SV5050 HTSSOP-B28
W (Typ) x D (Typ) x H (Max) 5.0 mm x 5.0 mm x 1.0 mm 9.7 mm x 6.4 mm x 1.0 mm
◼ AEC-Q100 Qualified*1 ◼ 4ch Current Driver for LED Drive ◼ Buck-Boost Current Mode DC/DC Converter ◼ Control DC/DC Converter Oscillation Frequency by
External Synchronized Signal
◼ LSI Protection Function (UVLO, OVP, TSD, OCP, SCP) ◼ LED Abnormality Detection Function (Open/Short) ◼ VOUT Discharge Function (Buck-Boost Structure
Limitation)
VQFN28SV5050
HTSSOP-B28
*1 Grade 1
BD81A44MUV-M
BD81A44EFV-M
Applications
◼ Automotive CID (Center Information Display) Panel
◼ Car Navigation ◼ Cluster Panel ◼ HUD (Head Up Display)
◼ Small and Medium Type LCD Panels for Automotive Use
Typical Application Circuit
Product structure : Silicon integrated circuit This product has no designed protection against radioactive rays
This product is protected by U.S. Patent No.7,235,954, No.7,541,785, No.7,944,189.
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Pin Configuration
VQFN28SV5050 (TOP VIEW)
Pin Description Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 -
Pin Name LEDEN1 LEDEN2
LED1 LED2 LED3 LED4 OVP ISET PGND OUTL DGND VDISC SW OUTH BOOT VREG
EN CS VCC SS COMP RT SYNC SHDETEN GND PWM FAIL1 FAIL2 EXP-PAD
Function Enable pin 1 for LED output Enable pin 2 for LED output LED output pin 1 LED output pin 2 LED output pin 3 LED output pin 4 Over voltage detection pin LED output current setting pin LED output GND pin Low side FET gate pin DC/DC converter output GND pin Output voltage discharge pin High side FET source pin High side FET gate pin High side FET driver power supply pin Internal constant voltage Enable pin DC/DC converter current sense pin Input power supply pin “Soft Start” capacitor connection Error Amp output Oscillation frequency setting resistor connect External synchronization input pin Short detection enable signal Small signal GND pin PWM light modulation signal input pin “Failure” signal output pin 1 “Failure” signal output pin 2 Back side thermal PAD (Connect to GND)
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Pin Configuration
HTSSOP-B28 (TOP VIEW)
Pin Description Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 -
Pin Name VCC SS COMP RT SYNC
SHDETEN GND PWM FAIL1 FAIL2
LEDEN1 LEDEN2
LED1 LED2 LED3 LED4 OVP ISET PGND OUTL DGND VDISC SW OUTH BOOT VREG
EN CS EXP-PAD
Function Input power supply pin “Soft Start” capacitor connection Error Amp output Oscillation frequency setting resistor connect External synchronization input pin Short detection enable signal Small signal GND pin PWM light modulation signal input pin “Failure” signal output pin 1 “Failure” signal output pin 2 Enable pin 1 for LED output Enable pin 2 for LED output LED output pin 1 LED output pin 2 LED output pin 3 LED output pin 4 Over voltage detection pin LED output current setting pin LED output GND pin Low side FET gate pin DC/DC converter output GND pin Output voltage discharge pin High side FET source pin High side FET gate pin High side FET driver power supply pin Internal constant voltage Enable pin DC/DC converter current sense pin Back side thermal PAD (Connect to GND)
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Block Diagram
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Description of Blocks If there is no description, the mentioned values are typical value.
1. Reference Voltage (VREG) VREG Block generates 5 V at EN = High, and outputs .