The document introduces the features and characteristics of LT3420/LT3420-1 chargers. The charger can charge 220μF to 320V flash capacitors and the charging time is 3.7 seconds.
The LT3420 and LT3420-1 are photoflash capacitor chargers designed for use in digital and film camera flash units. These devices utilize a flyback topology to charge capacitors up to 320V efficiently, with the LT3420 supporting up to 220uF and the LT3420-1 supporting up to 100uF. They feature an adaptive off-time control algorithm to maintain current-limited continuous mode operation and eliminate high inrush current.
| Charge Time (220uF to 320V) | 3.7 Seconds |
|---|---|
| Charge Time (100uF to 320V) | 3.5 Seconds |
| Input Supply Range | 1.8V to 16V |
| Controlled Peak Switch Current (LT3420) | 1.4A |
| Controlled Input Current (LT3420) | 840mA |
| Efficiency | >75% Typical |
| Package Types | 10-Lead MSOP, 10-Lead DFN |
The device supports charging capacitors up to 320V.
No, the design eliminates the need for a high voltage Zener diode.