The OPAx986 use a unique input architecture to eliminate the need for input protection diodes but still provide robust input protection under transient conditions. Conventional input diode protection schemes shown in Figure 6-1 can be activated by fast transient step responses and can introduce signal distortion and settling time delays because of alternate current paths, as shown in Figure 6-2. For low-gain circuits, these fast-ramping input signals forward-bias back-to-back diodes that cause an increase in input current and result in extended settling time.

Figure 6-1 OPAx986 Input Protection Does Not Limit Differential Input Capability

Figure 6-2 Back-to-Back Diodes Create Settling Issues

The OPAx986 feature a true high-impedance differential input capability for high-voltage applications. This patented input protection architecture does not introduce additional signal distortion or delayed settling time, making these devices an excellent choice for multichannel, high-switched, input applications. The OPAx986 tolerate a maximum differential swing (voltage between inverting and noninverting pins of the op amp) of up to 48V, making these devices a great choice for use as a comparator or in applications with fast-ramping or switched input signals.