battery backup circuit help

[bikashh]

Dear all,
I am designing a battery backup circuit for my microcontroller based device and need your help. according to me i've designed a circuit(attached) which iam not sure whether will work or not.please help.


thanks in advance

 

[IanP]

Your circuit needs some clarifications ..
The Vcc and GND wires are connected the opposite way around, but I guess that’s just drawing mistake ..
What voltage do you intend to supply the microcontroller with?
Once the current goes through a diode there will be voltage drop and depending on the diode type the drop will be roughly between 0.5V and 1V ..
If the microcontroller can tolerate voltages between 3V and 5V that’s fine, if it can’t you have to do something about it ..

IanP
:wink:

 

[bikashh]

the microcontroller is running from 3.3v which is given by an LDO.
but my main concern is will the sensing circuit work.
when the main supply is ON pin status is low and when the main supply is OFF pin status is high.
And also i wanted to know whether the diodes(schottky) are the right selection for battery backup.please reply.


Thanks in advance