LM324 input current without power

[Raymund Hofmann]

How would the good old LM324's input current at the + input with 2.5V at
the + input and a power supply 0-1V (and the - input in the same range)
be ?
Are there some unwanted diodes not shown in the schematic diagram of the
lm324 ?

I guess spice models are not very reliable for this.

Raymund Hofmann

 

[Larry Brasfield]

"Raymund Hofmann" <filter002@desinformation.de> wrote
in message news:da0rm5$145$1@online.de...

How would the good old LM324's input current at the + input with 2.5V at
the + input and a power supply 0-1V (and the - input in the same range)
be ?
Are there some unwanted diodes not shown in the schematic diagram of the
lm324 ?

Not the ones you are worried about. The inputs can be taken
to values considerably above the supply rail. Consult the
datasheet maximum ratings section. There is no harm in
operating the part within its input voltage rating.

I guess spice models are not very reliable for this.

Often not. Breakdown typically is not modeled.

--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Jim Thompson]

On Thu, 30 Jun 2005 15:22:12 +0200, "Raymund Hofmann"
<filter002@desinformation.de> wrote:

How would the good old LM324's input current at the + input with 2.5V at
the + input and a power supply 0-1V (and the - input in the same range)
be ?
Are there some unwanted diodes not shown in the schematic diagram of the
lm324 ?

I guess spice models are not very reliable for this.

Raymund Hofmann

Should be just leakage, you're looking into one base input of a
darlington lateral PNP differential stage. Supply voltage of 0-1V
shouldn't be sufficient to get any tail current going.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
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