Criteria to reduce failures induced from conveyed electromagnetic interferences on CMOS operational amplifiers

On the effectiveness of EMIRR to qualify OpAmps

“…The output of an OpAmp connected as voltage follower experiences a DC voltage offset when high frequency disturbances are injected into the input, but only a small amplitude distorted sinusoidal signal [5]. …”

A Case Study to Apprehend RF Susceptibility of Operational Amplifiers

“…Two elements generate EMI-induced offset: the current source I S which is related to slew rate limitation, and the voltage source V off_weak which is associated to weak distortion effect. The slew rate limitation is modeled according to (3), which depends on several parameters defined by (4) to (6). They are related to the open-loop static gain A 0 and the gainproduct bandwidth GBW of the op-amp, which is modeled by a simple RC circuit.…”

“…Several papers address the modeling of the EMI-induced issue linked to the weak distortion of the incoming disturbance [3] [4] [5]. Many others propose design changes to improve its immunity [6] [7] [8].…”

Design of a CMOS opamp input stage immune to EMI

“…For example (see Graffi et al 1997), if C T,p > C T,n , condition (18) can be met by adding a shunt capacitor ÁC T,n to C T,n of capacitance ÁC T;n ¼ C T;p À C T;n For a given layout, the values of parasitics required can be estimated with very good accuracy from process parameters, either analytically or by computer simulation 104…”