ON/OFF programming ofμA776 opamps allows any or all inputs to be on at given time. Switched outputs are combined in summing inverter A,. Voltage followers A1-A3 are programmed from on to off by Q1-Q3 and A5- A7. Noise gain of stage A4, is minimized when input channel is switched off. If sign inversion by A4, is undesirable, add inverter stage following A.. Any number of additional channels can be added. Programming pulses are applied to inputs of A,, A6, and A,.-W. G. Jung, "IC 0p-Amp Cookbook," Howard W Sams, Indianapolis, IN, 1974, p 419-421.
Required Field 
