is this circuit safe even without a supply? I am comparing it to the CN0241 (High-Side Current Sensing with Input Overvoltage Protection). I see that the front serial resistors are higher value (380k vs. 1k), but it is also 500 V vs. 36 V. And AD629 doesn't have any current limitting cicuitry.
In CN0240 (the AD629) does not have over voltage protection built in. Applying power to the part before applying an input signal is critical.
In CN0241 (ADA4096-2) it appears as though there is some built in over voltage protection that works regardless of a supply being present. If VCC=VEE=0V, the OVP will protect the device up to 32V. Page 20 of the ADA4096-2 datasheet provides information on this subject.
Thank you Neil,
I think I understood the case in CN241. But I was wondering about the AD629. What voltage the integrated high-value resistors can protect the OpAmp against. If I understand right, the demage comes from a high current through clamp diodes to supply circuits. (I mean the case, when the AD629 is not powered.) The current here is not limitted, but significantly lowered, isn't it? Is there any spec for this condition?