Part Number: OPA1692
Hello,
Our customer is suffering from reverse bias across IN+ to V+ during system shut down and he need to know this is possible to damage OPS1692 (see that attachment in detail).
While the system shut down, even though V(IN+) > (V+) + 0.5V of absolte max ratings, the input current is limitted 0.5mApeak by external resistance.
Does this phenomen make OPS1692 damaged ?
OPA1692 IN+ to V+ reverse bias.pdf
best regards,
Toshiro,
When checking to see if an input overstress voltage is a problem, you should look at both voltage and current. Also, you need to look directly on the op amp pin. If the input voltage is limited by a resistor so that the current is less than the absolute maximum current, then the part will not be damaged. In your case you have a 2.2k and a 3k input resistor. This will limit the input current to I = (5V - 0.6V)/(2.2k +3k) = 0.85mA. This calculation assumes that the power supply is at zero and the input signal is at 5V (worst case). In your situation, the input signal and supply voltage are actually pretty close together so the current would be much less. The abs max current is ±10mA. So, in your case, I don't think that electrical overstress is a concern. How to Protect Op amps from Electrostatic Discharge & Electrical Overstress Damage covers this topic in detail.
Best regards, Art
