Charge Pump Packs Camera Flash Timer

Powering white LEDs in camera flash applications, the AAT3170 current-output charge pump pairs a 600-mA dual regulated current output driver and a safety timer. The flash timer is programmable via an external capacitor and serves to protect the LED or to preset flash duration. Each LED output is programmable in 32 steps via a GPIO output through the company’s Advanced Simple Serial Control interface, which is a 32-step, single-wire interface that smoothes transitions and provides brightness control. The interface can also provide a regulated voltage instead of current for additional loads. The tri-mode device also teams a load switch (1x), fractional (1.5x) and doubling (2x) capabilities, and a sensing circuit to match the output to the LED. The 1x and 1.5x modes minimize current draw during lower-current operations. Additionally, the AAT3170 requires five external components: four 1 µF capacitors and one capacitor to set flash-timer duration. The device also features a thermal management system and soft-start circuit. In a lead-free, 12-pin 3 mm x 3 mm TDFN package, price is $1.82 each/1,000. ADVANCED ANALOGIC TECHNOLOGIES INC., Sunnyvale, CA. (408) 737-4600.