nramesh
Junior Member level 1
Hi,
I am using AC-DC conversion power supply design (by changing passive component values) from one of Analog device's application design. (AN-559 - A Low Cost Watt-Hour Energy Meter Based on the AD7755).
Capacitor divider circuit is used for power supply design (rectifier section). Capacitor (in this app note, C17) decides VA rating of the design. i need 1A@5V output from LDO (other appropriate rated device is used in the place of U2-7805). As per my calculation, it seems C17 should be 7~10uF with high voltage current rating (and R21 comes around 50 ohm). will it be !?! (But I don’t think values are correct. (Capacitor value ~10uF may not exist to handle 240Vac rating)
I am totally confused. Can you please help me in value calculation / cross checking?
Thanks in Advance,
Ramesh
I am using AC-DC conversion power supply design (by changing passive component values) from one of Analog device's application design. (AN-559 - A Low Cost Watt-Hour Energy Meter Based on the AD7755).
Capacitor divider circuit is used for power supply design (rectifier section). Capacitor (in this app note, C17) decides VA rating of the design. i need 1A@5V output from LDO (other appropriate rated device is used in the place of U2-7805). As per my calculation, it seems C17 should be 7~10uF with high voltage current rating (and R21 comes around 50 ohm). will it be !?! (But I don’t think values are correct. (Capacitor value ~10uF may not exist to handle 240Vac rating)
I am totally confused. Can you please help me in value calculation / cross checking?
Thanks in Advance,
Ramesh