How to Connect and Switch Between Two Current Amplifiers?

[Stellad]

Hello,

I want to connect 2 current amplifiers the same time and I want to be able to switch between them. How should I connect them? in series?

Thanks in advance,
//Stella

 

[Bob S]

I attach an LTSpice circuit diagram (Fig 1) for two operational amplifiers, both simultaneously attached in series to a single floating current source. The current source is set to 1 microamp DC. Both op amps have a 100 kohm feedback resistor. The Spice DC operating point analysis (Fig 2) shows that Vout1 is +0.1 volts, and Vout2 is -0.1 volts. A unity gain inverter could be used to invert either voltage output. The feedback resistor in either op amp circuit can be changed without affecting the other circuit, unless either op amp output exceeds about +/- 10 volts.