The opamp's output is NULL or Synchronized NULL, what does it mean?

[danny davis]

What does it mean when an op-amps output is NULL? or Synchronized NULL? they are both different but what do they mean? and why would you want an op-amps output to be NULL or Synchronized NULL?

 

[Audioguru]

You can null (cancel) the input offset voltage on an opamp with a trimpot. I have never heard of synchronized null.

 

[danny davis]

They aren't using the trim pot to null out the offset voltage like on the datasheets, i know what you're talking about , there is no trim pots in there circuits

I think a NULL output means: the Offset voltage has been Cancelled out some how

Example#1 says"

If the input voltage doesn't change, the op amps output is NULL

 

[FvM]

i know what you're talking about , there is no trim pots in there circuits

Unfortunately you didn't mention which circuits you are talking about.

 

[danny davis]

They are just 741 op-amps , the service manual says If the input voltage doesn't change, the op amps output is NULL

What does that mean when an Op amps output is NULL or synchronized null?

I can't upload the schematic because they are "controlled schematics" at my job sorry