Hi everyone

I like to know why lm358 can work with 0V in his -Vcc and other op-amp can't? for example lm741 can get there only voltage between -5 to -15 volt
When I looked on the schematic level I see no different between this two..

thank u a lot

 

Look again. First of all, the 741 uses NPN transistors on the input, and with the bases of the input diff pair grounded, requires a negative voltage on the emitters to put the transistors into a active state. The 358 uses PNP input transistors and can be properly biased without the negative supply.

 

Look at the input stage of an LM358 and examine the situation.

 

Hi everyone

I like to know why lm358 can work with 0V in his -Vcc and other op-amp can't? for example lm741 can get there only voltage between -5 to -15 volt
When I looked on the schematic level I see no different between this two..

thank u a lot

Vague recollection that the 358 might be DESIGNED for single rail work. You CAN use the 741 with the inputs referenced to a "virtual earth" - but its an ancient device with PSU requirements that might be unhelpful in modern designs.

 

Hi,

Most op amps can be used with a single supply if they are biased properly into linear operation.
There are some though that are designed for somewhat special purposes that require two different supplies. They are usually very high speed but you never know what might come out of the design factory these days.

 

Thank you all! really helpful