Datasheet Linear Technology LT3485-3

LT3485-0/LT3485-1/
LT3485-2/LT3485-3
Photoflash Capacitor
Chargers with Output Voltage
Monitor and Integrated IGBT Drive U DESCRIPTIO FEATURES The LTВ®3485 family of photoflash chargers are highly integrated ICs containing complete charger and IGBT drive
functions. The patented control technique of the LT3485-x
allows it to use extremely small transformers. Output voltage
detection requires no external circuitry. The turns ratio of the
transformer controls the final charge voltage. While charging,
the output voltage on the capacitor may be monitored by a
microcontroller from the monitor pin. Each device contains an
on-chip high voltage NPN power switch, which can withstand
negative voltages on the switch pin without an external
Schottky diode. The device features a VBAT pin, which allows
the use of two AA cells to charge the capacitor. The internal
circuitry operates from the VIN pin. The LT3485-0 has a
primary current limit of 1.4A, whereas the LT3485-3, LT3485-2,
and LT3485-1 have current limits of 2A, 1A and 0.7A respectively. These different current limits result in tightly controlled
input currents. Integrated IGBT Driver
Voltage Output Monitor
Uses Small Transformers: 5.8mm Г— 5.8mm Г— 3mm
Operates from Two AA Batteries, Single Cell Li-Ion
or Any Supply from 1.8V up to 10V …