Opamp differential Input specification

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ku637

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Hi

I have an opamp TLV2462 the opamp datasheet tells a specification states

Differential input voltage, VID . . . . . . . . . . . . . . . . . . . . − 0.2 V to VDD + 0.2 V

I'm using it in 5V supply
What does that exactly mean?

is it that (V+ terminal) - (V- terminal voltage) never ever exceed either -200mV or +5.2V in my case?

will that literally mean if ever in my design the negative terminal go beyond 200mV while positive terminal is held at 0V can kill my opamp.?

Thanks for any suggestion.
 

Hi,

I think there is an error in the datasheet.

DIFFERENTIAL input voltage range is either
* about +/-600mV for inputs with diodes between -IN and +In
* or about +/- VDD for non_diode inputs.
(for sure other values are possible)

*****

--> in any regulating OPAMP circuit the difference voltage will be close to zero. Only +/- some mV.

*****
The given value: "− 0.2 V to VDD + 0.2 V"...
more sounds like the absolute maximum for "common mode input voltage range"
(The recommended input voltage range is 0V ...VDD

Klaus
 
**broken link removed**

Indeed it is the input to supply rail variance
 
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    ku637

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That means its a common mode spec.. right?
 

A quick scan on yahoo turned up a fairly good page that may be worth reading:
Here's a quote:
"Another term used to describe op amp inputs is input common-mode range (VICMR), or more correctly input common-mode voltage range. This is the parameter most often used in datasheets and is also the one where circuit designers should be most concerned. VICMR defines a range of common-mode input voltages that results in proper operation of the op amp device, and describes how close the inputs can get to either supply rail."

The full page is at:
https://www.planetanalog.com/document.asp?doc_id=528175&site=planetanalog
 

You can have absolute (each input by itself), common mode
(average of inputs) and differential mode (difference of inputs)
limits, whether or not they are all called out. Some op amps
(esp. high speed) may have input cross-clamps to limit
wind-up that cause max Vdiff to be well less than supply
span. But this is not the case here, only an example of
how the three limit-cases may diverge based on internal
details.

200mV over-rail limit may pertain to input leakage specs or
to functionality. Hard conduction at ~600mV should be
expected but fine parameters may be compromised closer-in
(esp. if the part is proud of sub-nA input bias current etc.).
 

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