Part Number | Data Sheet | SPICE Model | Topologies (Buck) | Topologies (Buck-Boost) | Topologies (Boost) | MinimumInput Voltage (V) | MaximumInput Voltage (V) | Maximum Output Voltage (V) | LED Current (A) | Switching Frequency (kHz) | Efficiency (%) | OperatingTemperatureRange (°C) | QuiescentCurrentTyp (mA) |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
ZXSC440 | ZXSC4x0.pdf | - | - | - | Yes | 1.8 | 8 | VIN to VM | - | 200 | 85 | -40 to +85 | 0.22 |
The ZXSC440 is a dedicated photoflash charger, charging an 80μF photoflash capacitor to 300V in 3.5 seconds from a 3V supply. The flyback conversion efficiency is typically 75%, much higher than the commonly used discrete charging circuits. The Charge pin enables the circuit to be initiated from the camera's microprocessor, using negligible current when flash is not being used. The Ready pin signals the microprocessor when the flash is charged and ready to be fired. A small amount of hysteresis on the voltage feedback shuts down the device as long as the capacitor remains fully charged, again using negligible current.