Measuring current output while stimulating.

Discussion in 'The Projects Forum' started by suetibu, May 22, 2008.

  1. suetibu

    Thread Starter New Member

    May 22, 2008

    I have a current source that I can program to output a waveform (eg. biphasic, 2mA, 60 msecs cycle,..) to stimulate an electrode. I want to display on an oscilloscope the output current (i.e, the current actually being delivered). I tested the stimulator -100uA (without the electrode) with a 1kohm resistor and measured 1V on the oscilloscope. However am confused how to measure while stimulating. Electrode has an impedance of .5Mohm. Should I set up a resistor in series and measure the voltage across that? or should it be in parallel? Also if you know of any material available online that could help me understand current sources (voltage sources were explained in detail on this site), it will be much appreciated.