Battery/AC Adapter

[Urahara]

Hi

A basic question really.

For portable devices like radio, we can run it on batteries or via power that comes from an ac adapter.

I believe the radio circuitry detects and switches from battery to ac/dc power whenever we plug in the ac adapter.

Where can I find information abt how it does this, and what's available to do this if I want to add this capability to my microcontroller project.

Thks!

 

[Willbe]

the radio circuitry detects and switches from battery to ac/dc power whenever we plug in the ac adapter

PN 501J on the Connectors and Adaptors page from this link
www.hosfelt.com
is one way to do it.

 

[kchriste]

Usually the DC power jack on the side of the radio has a built in "switch" which disconnects the battery when the AC adapter is plugged into the radio.

 

[Urahara]

hmmm...simple yet straightforward solution now that you've mentioned it...thks!

To complicate the matter a little, what if i now hv a usb port on the microchip (eg 18F4550). What can one do to hv the uC system to, say, switch off, the battery or the ac adapter power and use the usb power that comes on from the PC.