This module is designed as a source for I-V measurements with remote control having a current range (10nA..10m A/V)
The output [symm/single] switch selects two output modes:
-single: pin 4 is the output node delivering the selected current/voltage, pin 2 is connected to ground (classic current source).
-symmetric: pin 4 is the output node delivering the selected current/voltage, pin 2 is a node at exactly the opposite voltage level of pin 4, driven by a low impedance source !(this is different from S4m/S4c).
The output voltage is then symmetrical to ground (if the sample is not grounded). Applications of symmetric operation are: preventing a common mode voltage across the sample, preventing a common mode voltage on the voltage amplifier, doubling the maximum voltage output swing of the current/voltage source. Selecting the symmetric mode gives 4..8V maximum output voltage.
The symmetric mode has a slightly higher noise level.
The module has a possibility for two inputs: x1 (sweep) and x0.01 (modulation). Default ONLY the x1 input is enabled in the module. The x0.01 input can be enabled/disabled by a jumper inside. The input signals are summed inside the module.
When the internal amp voltage exceeds 4 Volt (loadresistance dependant) on the control panel(not on the module) an overload LED [clip] indicates an error. The sample resistance is then too high for the given current or the controlling voltage is too high.
The [V/A] rangeswitch sets the output current to give 100% at 1V control input on the Iso-amp or 1V output of the controlling DAC
output: Iout=Vin(Iso-amp1 or DACn) * [RANGE] + 0.01 * Vin(Iso-amp2 or DACm )*[RANGE]
lemo [OUT] pin 4/2/3 connection:
single: 4=out / 2=ground / 3=ground
symm: 4=out / 2=-out / 3=ground
for IVVI-rack only: Enabling x0.01 means that only ONE source can be used in the rack.
(both Iso-amps are used then to provide the x1 and x0.01 signal)