Overall Instrument Operation - Agilent Technologies E4991A Service Manual

Theory of Operation

Overall Instrument Operation

Overall Instrument Operation
The E4991A consists of a mainframe, a test head and a calibration kit as shown in Figure
5-1. The mainframe includes a signal source, a receiver, a digital control, and a power
supply section.
The signal source generates a stimulus signal in the frequency range from 1 MHz to 3 GHz.
The stimulus signal goes through the test head, and the test fixture to the device under test
(DUT).
The test head detects the voltage across the DUT and the current through the DUT, and
transfers the detected signals to the receiver section.
The receiver converts the analog signals to a digital data and forwards it to the digital
control section.
The calibration kit is used to calibrate the E4991A system. Calibration ensures the
impedance measurement accuracy at the measurement terminal of the test head.
The power supply in the mainframe supplies all necessary dc power for the E4991A.
Figure 5-1
Connection between each assembly in the mainframe is shown in Figure 5-2 system block
diagram.
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