Differential and common mode over-range indicator for In-amp
A &quot;few&quot; resistors and diodes added and only the two extra op. amps. would be acceptable?

The initial idea would be to monitor if any of the 3 op. amp. outputs go above or below the 2 voltage references. It would not be very precise due to the diode voltage drops.

The diodes are available in &quot;pairs&quot;: