The device is designed to be used in boost, buck-boost and flyback converter topologies. The LED current may be set via an external sensing resistor, and is adjustable within a range of ±66.7% by a host microcontroller via the device’s serial peripheral interface. The L99LD01 may be used either with an MCU or as a stand-alone device.
An internal random dither oscillator provides for low-frequency modulation, allowing the RF spectrum of the switching frequency to spread so as to reduce the external effect of the driver’s electro-magnetic emissions. Slope compensation ensures good loop stability whatever the duty cycle needed by the application.
The converter is able to work either in full-power mode or in low-frequency dimming mode. It includes an internal low-drop voltage regulator which may be used to supply an MCU with a regulated 5V input. It also has a Reset pin, which is useful for resetting the MCU at start-up, and every time that the regulated output voltage falls below a set threshold.
- Automotive qualified
- Maximum input-current limiter
- Maximum switching duty-cycle limiter
- Battery over-voltage shut-down protection
- LED chain over-voltage detection
- Power-on Reset pin
- ESD protection
- Daytime running lights