I'm looking to use the ADP3303 in a relatively low-current (<< the 200mA limit of the '3303) 5->3.3V application, with a large capacitor on the output to hold up the 3.3V supply for a short period of time after 5V dies so that the system can log the power-fail event to NVM before all the lights go out. However, the datasheet leaves a few things unanswered, which is why I'm posting here.
- What is the voltage threshold at which the ERR pin flags? (A percentage of Vout(nom) or Vin(dropout) will suffice here.)
- How long does it take from the threshold being reached to the ERR pin going LOW? (Propagation delay, basically.)
- What happens to the ADP3303 when Vin is driven to 0V while Vout is held up? (Assume that the SD pin is tied to Vin.) Does it fry, act as a diode from OUT to IN, or sit there and be an almost-open-circuit? (If it is the latter, how much leakage current can I expect at OUT?)