Test Instruments

The HP 4141, Agilent 4142, or HP 4145 can be used to derive DC model parameters from measured DC voltage and current characteristics.

The Agilent 8510, Agilent 8753, or HP 8702 (with an HP 41xx instrument) can be used to derive capacitance and inductance model parameters from S-parameter measurements.

Instrument-to-Device Connections

When the device is installed in a test fixture, verify the identity of device nodes by checking the inputs and outputs for the appropriate DUTs. The following table is a cross reference of the connections between the terminals of a typical MESFET device and various measurement units. These connections and measurement units are defined in CGaas1.mdl and CGaas2.mdl example files.

Input and output tables in the various setups use abbreviations D (drain), G (gate), and S (source) for the MESFET device nodes. These nodes are defined in the Circuit folder.

Measurement units (abbreviated as follows) are defined in Hardware Setup.

SMU# for DC measurement units
NWA for network analyzer units

Table 91 Instrument-to-Device Connections

DUT	Source	Gate	Drain	Comments
dc	SMU3	SMU2	SMU1
ac	Ground	SMU2 NWA (port 1)	SMU1 NWA (port 2)	Calibrate for reference plane
Notes: 1. DUT is the name of the DUT as specified in DUT-Setup. Source, Gate, and Drain are the names of the transistor terminals. 2. As an example of how to read the table, the first line indicates that the DUT named dc has the DC measurement instruments SMU1 connected to its drain, SMU2 connected to its gate, and SMU3 connected to its source.