Agilent Technologies 90B manual Digital Current Source DCS

Status Feedback. Three feedback lines are available to furnish continuous status information to the controller. A flag line informs the computer when new voltage programming data is being processed by the DVS. Current overload and latch lines are activated if the DVS experiences a current overload or latch condition.

Digital Current Source (DCS)

The DCS is a bipolar Constant Current/Voltage Limiting power source. A DCS unit contains most of the same circuit elements that were shown for a DVS unit; including, interface and isolation circuits, storage, D/A converter, and a bi-polar output amplifier. One difference is, of course, that a DCS unit has a programmable voltage limit circuit rather than a programmable overcurrent circuit. The voltage limit circuit returns two overload status signals to the controller in a manner similar to the DVS overcurrent circuit.

The DCS also employs guarding techniques that are conceptually identical to those of the Precision Constant Current Source described earlier in this section. As mentioned previously, these guarding techniques prevent the flow of leakage current and allow a more precise regulation of the output current.

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