DESCRIPTION
The LT®3420/LT3420-1 charge high voltage photoflash capacitors quickly and efficiently. Designed for use in both digital and film cameras, these devices use a flyback topology to achieve efficiencies up to four times better than competing flash modules. A unique adaptive off-time
control algorithm* maintains current-limited continuous mode transformer operation throughout the entire charge cycle, eliminating the high inrush current often found in modules.

FEATURES
■ Charges 220µF to 320V in 3.7 Seconds from 5V (LT3420)
■ Charges 100µF to 320V in 3.5 Seconds from 5V (LT3420-1)
■ Charges Any Size Photoflash Capacitor
■ Supports Operation from Two AA Cells or Any Supply from 1.8V to 16V
■ Controlled Peak Switch Current: 1.4A (LT3420) 1.0A (LT3420-1)
■ Controlled Input Current: 840mA (LT3420) 450mA (LT3420-1)
■ Uses Standard Transformers
■ Efficient Flyback Operation ( >75% Typical)
■ Adjustable Output
■ Automatic Refresh
■ Charge Complete Indicator
■ No High Voltage Zener Diode Required
■ No Output Voltage Divider Required
■ Small 10-Lead MSOP Package

APPLICATION
■ Digital Camera Flash Unit
■ Film Camera Flash Unit
■ High Voltage Power Supplies