Multichannel Systems STG4002 Manual - Manual (Page 72)

Stimulus Generator 4002 Manual
68
11.2
Voltage Mode
 If you want to operate the STG in voltage mode, you have to select "Voltage" in Output Mode
of the main window of MC_Stimulus II. You will usually use the + and GND outputs. The output
signal is identical with the programmed signal in the normal ranges of the electronics' accuracy.
See illustration "Voltage mode: Standard Setup".
 The output signals are inverted (multiplied by -1) if you use the - outputs.
 If you use the voltage between + and -, the output signal amplitude is doubled. The - represents
the ground (replaces GND) in this case. See illustration "Voltage mode: Doubled output signal
amplitude".
 A bipolar stimulation is recommended for extracellular recordings from microelectrode
arrays (MEAs) if a very high output signal density in a defined area between two neighboring
stimulating electrodes is needed. The current that is delivered by the first electrode flows directly
back to the second electrode so that the surrounding tissue is not affected. See illustration
"Voltage mode: Bipolar stimulation".
 In the following example, you see a signal in the MC_Stimulus II display and the resulting
output signals for the different connection options (viewed in a MC_Rack Data Display).
Programmed stimulus protocol viewed in MC_Stimulus
STG output signals: +U to GND