Agilent Technologies 4155C, User Manual

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4-12 Agilent 4155C/4156C VXIplug&play Driver User’s Guide, Edition 4
Programming Examples for Visual Basic .NET Users
Staircase Sweep Measurements
Staircase Sweep Measurements
This section explains an example subprogram that performs staircase sweep
measurement. This example measures MOSFET Id-Vd characteristics.
Table 4-4 Staircase Sweep Measurement Example
Sub perform_meas(ByVal Ag415x As Hp4156b) ’1
Dim i As Integer = 0
Dim j As Integer = 0
Dim nop1 As Integer = 11
Dim nop2 As Integer = 3
Dim data(nop2, nop1) As String
Dim val As String = "Vg (V), Vd (V), Id (mA), Status"
Dim fname As String = "C:\Agilent\data\data3.txt"
Dim title As String = "Sweep Measurement Result"
Dim msg As String = "No error."
Dim err As Integer = 0
Dim t() As Integer = {1, 2, 3, 4} ’13
Ag415x.SetSwitch(t(3), 1) ’SMU4: substrate
Ag415x.SetSwitch(t(2), 1) ’SMU3: source
Ag415x.SetSwitch(t(1), 1) ’SMU2: gate
Ag415x.SetSwitch(t(0), 1) ’SMU1: drain
Dim vd1 As Double = 0 ’19
Dim vd2 As Double = 3
Dim idcomp As Double = 0.05
Dim vg1 As Double = 1
Dim vg2 As Double = 3
Dim igcomp As Double = 0.01
Dim vg As Double = vg1 ’secondary sweep output value
Dim d_vg As Double = 0 ’secondary sweep step value (delta)
If nop2 <> 1 Then d_vg = (vg2 - vg1) / (nop2 - 1)
Dim hold As Double = 0
Dim delay As Double = 0
Dim s_delay As Double = 0
Dim p_comp As Double = 0
Dim rep As Integer = nop1
Dim sc(nop1) As Double ’primary sweep output data
Dim md(nop1) As Double ’sweep measurement data
Dim st(nop1) As Integer ’status data at each step
’36
Line Description
2 to 11 Declares variables used in the program template. And sets the proper values.
13 to 17 Enables measurement channels.
19 to 36 Declares variables and sets the value.