A80602 andHigh Power LED Driver with Pre-Emptive BoostA80602-1 for Ultra-High Dimming Ratio and Low Output RippleELECTRICAL CHARACTERISTICS [1]: Unless otherwise noted, specifications are valid at VIN = 12 V, TJ = 25°C, • indicates specifica-tions guaranteed over the full operating temperature range with TJ = –40°C to 125°C, typical specifications are at TJ = 25°CCharacteristicsSymbolTest ConditionsMin.Typ.Max.UnitINPUT VOLTAGE SPECIFICATIONS Operating Input Voltage Range [3] VIN ● 4.5 − 40 V VIN UVLO Start Threshold VUVLO(rise) VIN rising ● − – 4.45 V VIN UVLO Stop Threshold VUVLO(fall) VIN falling ● − – 4.05 V UVLO Hysteresis [2] VUVLO_HYS 300 400 500 mV INPUT CURRENTS VIN Pin Operating Current I EN and PWM = H, CGATE = 1 nF from GDRV to OP PGND, fSW = 2 MHz ● − 22 32 mA VIN Pin Sleep Current ISLEEP VIN = 16 V, VEN / VPWM = VSYNC = 0 V ● − 1 5 µA INPUT LOGIC LEVELS (EN/PWM, ADIM) Input Logic Level-Low VIL ● − − 0.4 V Input Logic Level-High VIH ● 1.5 − − V Input Pull-Down Resistor REN/PWM, R Input = 5 V 30 50 70 kΩ ADIM ANALOG DIMMING (ADIM) Analog Dimming Current Level iADIM50 DC 1.0 V applied to ADIM pin − 50 − % (shown as % of full-scale current) iADIM25 DC 0.5 V applied to ADIM pin 23 25 27 % APWM Frequency Range [2] fAPWM Clock signal applied to ADIM pin ● 40 − 1000 kHz APWM Duty Cycle Range [2] DAPWM Clock signal applied to ADIM pin ● 0 − 90 % VDD REGULATOR Regulator Output Voltage VDD VIN > 6 V, iLOAD < 1 mA 4.05 4.25 4.45 V VDD UVLO Start Threshold VDDUVLOrise VDD rising, no external load − 3.2 − V VDD UVLO Stop Threshold VDDUVLOfall VDD falling, no external load − 2.65 − V ERROR AMPLIFIER Amplifier Gain [2] gm VCOMP = 1.5 V − 900 − μA/V V Source Current I COMP = 1.5 V, A80602 (symm COMP) − –500 − μA EA(SRC) VCOMP = 1.5 V, A80602-1 (asymm COMP) − –700 − μA Sink Current IEA(SINK) VCOMP = 1.5 V − +500 − μA COMP Pin Pull Down Resistance RCOMP FAULT = 0, VCOMP = 1.5 V − 1.4 − kΩ Continued on the next page… Allegro MicroSystems, LLC 6 955 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