JAJSM26C September 2000 – January 2022 INA126 , INA2126
PRODUCTION DATA
The input common-mode range of the INAx126 is shown in Section 6.7. The common-mode range is limited on the negative side by the output voltage swing of A2, an internal circuit node that cannot be measured on an external pin. The output voltage of A2 can be expressed as shown in Equation 2:
where
The internal op amp A2 is identical to A1, with an output swing typically limited to 0.7 V from the supply rails. When the input common-mode range is exceeded (A2 output is saturated), A1 can still be in linear operation and respond to changes in the noninverting input voltage. The output voltage, however, will be invalid.