Variable bipolar clamp circuit

The precision comparator provides independent regulation of the two output voltage limits without the need to connect to the comparison input. A2 and A3 are complementary precision rectifiers with independent positive and negative reference voltages, both of which operate in a closed loop through A1. A2 senses the positive peak of EO and equals the positive clamp voltage by adjusting the D1 voltage. A3 and D3 have similar functions at negative peaks. The feedback network of the A1 output stage independently regulates the output voltage to A1.