The AT1453 is a charger control IC for Photoflash capacitor with soft start function, adjustable maximum duty cycle and auto-discharge (soft start capacitor) circuit. Adjustable soft start is programmed with an external capacitor on SS pin. The control technique allows for the use of external resistor to change the switching duty and use of transformer to control the input current. A logic high on the CHARGE pin initiates charging, while the READY pin signals that the capacitor is fully charged. It is ideal for DSC flash unit.