Single Supply Op-Amp with Negative Ouput

[monster]

Is that possible to design single supply op amp (O-5V) rail-to-rail, to provide a negative ouput voltage?

 

[audioguru2]

The opamp can oscillate and drive a "charge pump" made with a couple of diodes and a couple of capacitors. Then the negative DC output will be about -3.6V if the load current is low.

Use an ICL7660 charge pump IC to create a negative DC supply voltage for the opamp. The output will be -5.0V if the load current is very small and will drop due to its 23 ohms source resistance. So a 10mA load will drop the output voltage to -4.77V.

View attachment 40330

 

[monster]

thanks audioguru for the suggested solution. ;D