Allegro MicroSystems ALT80802 Adjustable Frequency Buck 2A LED Driver
Allegro MicroSystems ALT80802 Adjustable Frequency Buck 2A LED Driver is AEC-Q101 qualified and supports buck-boost or buck-mode operation. This high-frequency switching regulator provides constant output current to drive high-power LEDs and integrates a power MOSFET for step-down or inverting buck-boost conversion. The ALT80802 is constructed to aid EMC/EMI design with frequency dithering, soft freewheel diode turn-off, and well-controlled switch node slew rates. A programmable oscillator enables the ALT80802 to switch outside EMI-sensitive frequency bands, such as the AM band. This driver can achieve fast transient response with current-mode control and simple external compensation, and the control loop is designed for PWM dimming operation to achieve low dimming on-time and low turn-on overshoot. When in buck-boost operation, the ALT80802 reduces the current overshoot normally caused by the right half plane zero effect during a PWM dimming turn-off transient. Allegro MicroSystems ALT80802 Adjustable Frequency Buck 2A LED Driver offers a 3.8V to 50V input voltage range, making it suitable for a wide range of lighting applications, including those in an automotive input environment.Features
- Automotive AEC-Q100 qualified
- Supports buck-boost or buck-mode operation
- Supply voltage from 3.8V to 50V in buck mode
- Handles automotive load dump and cold crank
- Also supports buck mode from a pre-boost supply
- Supports up to 16V output in buck-boost mode for 4 WLEDs
- 150mΩ integrated MOSFET switch
- Programmable switching frequency up to 2.5MHz for small solution size and operation above AM band
- Designed for low EMC with frequency dithering
- Integrated level shifting allows ground-referenced enable and fault flag in buck-boost mode
- PWM dimming via direct logic input or power supply voltage
- Robust Protection Against
- Adjacent pin-to-pin short
- Pin-to-VSS (IC ground) short
- Component open/short faults
Applications
- Automotive Lighting
- Daytime running lights
- Front and rear fog lights
- Turn/stop lights
- Map light
- Dimmable interior lights
Specifications
- -0.3V to 55V input voltage range
- 10-pin DFN package with thermal pad and wettable flank
- 150mΩ MOSFET on resistance
- 80ns minimum on-time PWM
- -40°C to +150°C junction temperature
Schematic
Additional Resources
Publié le: 2023-05-16
| Mis à jour le: 2023-05-25
