A80602 andHigh Power LED Driver with Pre-Emptive BoostA80602-1 for Ultra-High Dimming Ratio and Low Output Ripple VIN D1 VOUT ≤ 40 V L1 4.7 µF Q1 R C OVP1 OUT ROVP2 CVDRV VIN GATE GDRV PGND GATE GDRV PGND VSENSE VDRV CS VSENSE VDRV CS V OVP C C VIN OVP CVDD VIN VDD VDD VDD 10 kΩ LED1 A80602-1 LED1 A80602-1(MASTER) FAULT LED2 (SLAVE) FAULT LED2 EN/ LED3 EN/ LED3 PWM ... PWM ... LED6 LED6 Up to 140 mA × 6 Up to 140 mA × 6 ADIM ADIM COMP COMP AGND ISET FSET DITH PEB AGND ISET FSET DITH PEB RZ CP R RM R R ISET R ISET RFSET RPEB2 FSET C PEB1 CZ M Figure 5: Two A80602-1 connected in Master/Slave Configuration to drive 140 mA × 12 LED stringsRemarks on Master-Slave configuration: • Only one Slave to a Master. • Master-Slave operation requires asymmetrical COMP (for example: source = –700 µA and sink = 500 µA). This is available in A80602-1 only. • Also requires bidirectional FAULT pin of A80602-1, so that the slave can halt the switching of master. Allegro MicroSystems, LLC 10 955 Perimeter Road Manchester, NH 03103-3353 U.S.A. www.allegromicro.com Document Outline Features and Benefits Description Applications Package Selection Guide Absolute Maximum Ratings Thermal Characteristics Typical Application – SEPIC Functional Block Diagram Pinout Diagram and Terminal List Electrical Characteristics Functional Description Enabling the IC Powering Up: LED Detection Phase Powering Up: Boost Output Undervoltage Soft Start Function Frequency Selection Synchronization Loss of External Sync Signal Switching Frequency Dithering LED Current Setting PWM Dimming Pre-Emptive Boost (PEB) Analog Dimming ADIM Mode APWM Mode Extending LED Dimming Ratio Analog Dimming with External Voltage VDD VDRV Shutdown Fault Detection and Protection FAULT Status LED String Partial-Short Detect Overvoltage Protection Boost Switch Overcurrent Protection Input Overcurrent Protection and Disconnect Switch Setting the Input Current Sense Resistor Input UVLO Fault Protection During Operation Package Outline Drawing Appendix: External MOSFET Selection Guide