7.1 Overview

The LM36010 is a high-power white LED flash driver capable of delivering up to 1.5 A to the LED. The device incorporates a 2-MHz or 4-MHz constant frequency-synchronous current-mode PWM boost converter and a high-side current source to regulate the LED current over the 2.5-V to 5.5-V input voltage range.

The LM36010 PWM DC-DC boost converter switches and boosts the output to maintain at least V_HR across the current source. This minimum headroom voltage ensures that the current source remains in regulation. If the input voltage is above the LED voltage + current source headroom voltage the device does not switch, but turns the PFET on continuously (pass mode). In pass mode, the drop across the current source is the difference between (V_IN - I_LED × R_PMOS) and V_LED.

The device has one logic input for a hardware flash enable (STROBE). This logic input has an internal 300-kΩ (typical) pulldown resistor to GND.

Additional features of the device include an input voltage monitor that can reduce the flash current during low V_IN conditions and a temperature based current scale-back feature that forces the flash current to the set torch level if the on-chip junction temperature reaches 125°C.

Control is done via an I²C-compatible interface. This includes adjustment of the flash and torch current levels, changing the switch current limit, and changing the flash time-out duration. Additionally, there are flag and status bits that indicate flash current time-out, LED over-temperature condition, LED failure (open/short), device thermal shutdown, thermal current scale-back, and V_IN undervoltage conditions.