Have Questions? Let us help!
We're passionate about innovation. Reach out and you'll hear back from an expert shortly.
One of our solution experts will be in touch with you shortly. Keep reading to learn more about our industry leading solutions.
The ALT80802 is a high-frequency switching regulator that provides constant output current to drive high-power LEDs. It integrates a power MOSFET for step-down or inverting buck boost conversion. The wide input range of 3.8 to 50 V makes the ALT80802 suitable for a wide range of lighting applications, including those in an automotive input environment. The device rating also enables a simple solution for driving 3 to 4 WLEDs in buck boost configuration—a very common application requirement for automotive lighting applications.
The ALT80802 is designed to aid in EMC/EMI design by frequency dithering, soft freewheel diode turn-off, and well controlled switch node slew rates. A programmable oscillator allows the ALT80802 to switch outside EMI-sensitive frequency bands such as the AM band.
With current-mode control and simple external compensation, the ALT80802 can achieve fast transient response. The control loop of the ALT80802 is designed for PWM dimming operation to achieve low dimming on-time and low turn-on overshoot. In buck-boost operation, the ALT80802 reduces the current overshoot normally caused by right half plane zero effect during a PWM diming turn-off transient. Extensive protection features of the ALT80802 include pulse-by pulse current limit, hiccup mode short-circuit protection, open/ short freewheeling diode protection, BOOT open/short voltage protection, VIN under voltage lockout, and thermal shutdown. Also, it includes internal clamp to prevent output voltage runaway if output LED string is opened in buck-boost operation.
The ALT80802 is available in a small 10 pin DFN package with thermal pad and wettable flank (automotive qualified).
10 Lead QFN
|Design Considerations in Selection of Converter Configuration for Automotive LED Headlight Applications
|ALT80802 Evaluation Board User Guide