Datasheet A80602, A80602-1 (Allegro)

A80602 and A80602-1 High Power LED Driver with Pre-Emptive Boost for Ultra-High Dimming Ratio and Low Output Ripple FEATURES AND BENEFITS DESCRIPTION
• Automotive AEC-Q100 qualified The A80602 is a multi-output LED driver for automotive • Enhanced fault handling for ASIL B system compliance applications such as exterior lighting, heads-up display, and mid- • Wide input voltage range of 4.5 to 40 V for start/stop, size LCD backlighting. It implements a current-mode boost/ cold crank, and load dump requirements SEPIC converter with gate driver for external N-MOSFET. This • Operate in Boost or SEPIC mode for flexible output allows greater output power even at minimum supply voltage. • Gate driver for external NMOS to deliver higher output power The A80602 provides six integrated current sinks driving up to • Six integrated LED current sinks, up to 140 mA each 140 mA per string. Multiple sinks can be paralleled together to • Boost switching frequency synced externally or achieve higher LED currents up to 840 mA. The IC operates programmed from 200 kHz to 2.3 MHz from single power supply from 4.5 to 40 V; once started, it can • Programmable boost frequency dithering to reduce EMI continue to operate down to 4 V. This allows it to withstand • Advanced control allows minimum PWM on-time down stop/start, cold crank, and load dump conditions encountered to 0.3 µs, and avoids MLCC audible noises in automotive systems. • LED contrast ratio: 15,000:1 at 200 Hz using PWM dimming alone, 150,000:1 when combining PWM and The A80602 can control LED brightness through external PWM analog dimming signal. By using the patented Pre-Emptive Boost control, an LED • Excellent input voltage transient response even at lowest brightness contrast ratio of 15,000:1 can be achieved using PWM PWM duty cycle dimming at 200 Hz. A higher ratio of 150,000:1 is possible when • Gate driver for optional PMOS input disconnect switch using a combination of PWM and analog dimming. • Extensive fault protection features Continued on next page...
PACKAGE: APPLICATIONS 24-Pin 4 mm × 4 mm QFN
• Automotive infotainment backlighting
with Wettable Flank
• Automotive heads-up display • Automotive interior and exterior lighting Not to scale VIN *optional VOUT R L1 SENSE D1 Q1 Cin RADJ ROVP R C GDRV RCS DRV COUT GATE VDRV GDRV CS PGND Vsense VIN Vc CVDD OVP VDD RPU LED1 FAULT
A80602
LED2 Up to 11 WLEDs in series Up to 140 mA/channel EN/PWM LED3 Combine to drive up to 840 mA total PWM t ... ON ≥ 0.3 µs ADIM LED6 iLED COMP 100% AGND ISET FSET DITH PEB ADIM RZ CP PEB = Pre-Emptive Boost R RM ISET RFSET C RD M C (R Z APWM 100 kHz 0-90% D controls the delay time) DITH = Dithering Control (Modulation frequency and range)
Figure 1: A80602 in Boost configuration where VOUT is higher than VIN
A80602-DS March 4, 2019 MCO-0000620 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