A8517is a programmable multi-output for a variety of LED driver applicationsLED drivers。 The driver incorporates a current boost regulator with built-in power switches and 10 current sinks. The IC operates from 4.5 to 36 volts and can withstand load dumps up to 40 volts found in automotive systems.
I2The C interface allows the user to individually set the LED current up to 60 mA per LED channel. Adjacent channels can be combined to drive higher current strings of LEDs. The PWM dimming duty cycle can be controlled individually for each LED channel, and each channel can be enabled/disabled independently if required.
This flexibility makes the A8517 a single solution for a variety of LED applications, where in some cases two or more LED driver ICs are replaced with one device.
The optimized control loop enables extremely high dimming ratios using only PWM controls, smoothly reacts to supply voltage transients and step changes, and eliminates night flashes generated by display backlight applications when starting at very low PWM duty cycles.
The A8517 detects and prevents a variety of fault conditions and reports fault status via dual communication. It has output short-circuit and overvoltage protection, open-circuit or short-circuit diode protection, open-circuit or short-circuit LED pin protection, short-circuit boost switch or inductor protection, and IC overtemperature protection. Dual cycle-by-cycle current limit prevents switching overcurrent in the built-in switches. If required, the IC can drive an external PFET that acts as an input disconnector, which is triggered by an integrated current sensor.
Apply:
Car:
- Infotainment
- cluster
- Vehicle center stack panel lighting
- Head-up display (HUD)
- Daytime Running Lights (DRL)
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- Wide AEC Q100 validated input voltage range of 4.5 to 36 volts
- Withstands as low as 3.9 volts (VIN drop) and load dump up to 40 volts
- Integrated boost regulator with DMOS switch for overvoltage protection up to 39 V
- 10 fully integrated current sinks with individually programmable currents up to 60 mA per channel
- I2C™ interface for programming LED current, PWM dimming, and individual protection thresholds per channel
- Use a single IC to drive multiple loads
- Wide PWM dimming range (up to 10,000:1 at 100 Hz) that can be individually programmed for each channel
- Extensive diagnostics and fault reporting
- Thermal warning and LED current derating at higher temperatures
- Buffered PWM dimming control for all channels to facilitate local dimming applications
- Multiphase PWM dimming: Variegatedly tuned LED current to reduce flash and input ripple current
- Synchronous boost switching frequency: 400 kHz to 2.3 MHz, allowing operation below or above the AM segment
- Programmable frequency jitter to reduce EMI
- Typical LED current accuracy is 0.7% and LED-to-LED matching accuracy is 0.8%.
- Protection features
- Open/short LED pin detection
- Programmable LED string short-circuit detection
- Open/short external components (including boost inductors, Schottky diodes, FSET resistors, etc.)
- Input overcurrent protection against short-circuits from output to GND
- Cycle-by-cycle switching current limit
- Over-temperature, output overvoltage, and under-voltage protection