AD835: Maximum input signal

Document created by analog-archivist Employee on Feb 23, 2016
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Some years ago we used the AD835AR in one of our designs. A new customer wants
to know if our board is not damaged when he applies a signal to it which is
slightly out of the boards spec. This signal results in a +/-4V (max) input
signal on the Y1 input of the AD835.
The specification or datasheet of the AD835 does not include a absolute maximum
rating of the inputs.
Is the AD835 damaged when a input signal of +/-4V is applied?


The max i/p common mode voltage and differential voltage for an op-amp is
generally the supply voltage. Assuming that the ctm is using +/-5V supplies,
then applying a voltage of +/-4V to the op-amp i/p will not damage the device,
eventhough the op-amp is only specified for +/-3.5V common mode i/p voltage.

What we are saying in effect, is that for specified operation of the device in
terms of the specifications given on page 2 and 3, you should operate within
the common mode voltage range (note: we don’t specifiy an i/p differential
operating voltage as feedback will pull the i/p’s to the common mode voltage of
the circuit), and to avoid stress plus possible permanent damage you should
keep the i/p voltage at or below the supplies.