Pico ammeter


Posted on Apr 12, 2012

Care must be taken to eliminate any stray currents from flowing into the current summing node. This can be accomplished by forcing all points surrounding the input to the same potential as the input. In this case the potential of the input is at virtual ground, or OV. Therefore, the case of the device is grounded to intercept any stray leakage currents that may otherwise exist between the ±15 V input terminals and the inverting input summing junctions. Feedback capacitance should be kept to a minimum in order to maximize the response time of the circuit to step function input currents.


Pico ammeter
Click here to download the full size of the above Circuit.

The time constant of the circuit is approximately the produce of the feedback capacitance C^ times the feedback resistor R^. For instance, the time constant of the circuit is I sec if C^, = lpF. Thus, it takes approximately 5 sec (5 time constants) for the circuit to stabilize to within 1% of its final output voltage after a step function of input current has been applied. of less than 0.2 to 0.3 pF can be achieved with proper circuit layout.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Flashing Lamps
    Water Activated Relay circuit board
    PreamplifierCircuit DCF77
    LNB Cable Data Transceiver Circuit Schematic Diagram
    Whats the third wire on a piezo buzzer
    ADum3223 issue (H bridge)
    Automatic 12 Volt Lamp Fader
    Phantom and T powering for condenser microphones
    Spectrum Keyboard Buffer
    Ophthalmology light lamp switch circuit
    Has 50 times the pre-amplified bridge circuit diagram XTR106



    Top