Hfe And Vbe(On) Versus Ic Measurement - Keysight Technologies B1505A Handbook

3-1-2. hFE and Vbe(on) versus Ic measurement

Measurement Parameters: hFE, Vbe(on)
Application Test name: hFE_Vbe-Ic
Application Test setup name (My Favorite Setup -> Example_AT): hFE_Vbe-Ic
Device used in the example: MJL4281AG
Connection inside the N1259A Test Fixture: Use figure 3-3 or 3-4
Application description:
Measures hFE-Ic and Vbe(on)-Ic characteristics. SMU pulse is used for Collector
current output and Base current output.
This measurement sweeps the base current, but the measurement output displays
the collector current in X axis as the dependent sweep parameter. Because the col-
lector current is the dependent parameter of the base current, the start and stop
parameters of the base current (Ibstart and Ibstop) have to be decided by consider-
ing the hFE of the measurement device to properly display the measurement result
in the graphics.
A. Measurement Procedure: hFE_Vbe-Ic Application Test,
-Starting from Application Test Library
This test approach starts measurements by using an Application Test Library, which
starts from the default setup parameters, and you have to customize the measure-
ment parameters depending on your requirements.
Setup and execute the test by following the next steps. The same instruction steps
are illustrated by the numbers on the "1. Starting from Application Test Library" side
of figure 3-7
Step 1. Click the Application Test tab.
Step 2. Check the PowerBJT category.
Step 3,4. Select hFE_Vbe-Ic (Click the hFE_Vbe-Ic then click Select
Step 5. Set the test parameters shown in figure 3-7 to an appropriate one depending
age
on your B1505A configuration and your test device.
The important check points are;
a. Base SMU setup
b. Ib sweep parameters
Note: Ib start and Ib stop parameters are roughly determined by the fol-
lowing formula; "target Ic start/hFE at low current" and "target Ic stop/
hFE at large current".
DC current gain, Base-Emitter on volt-
)
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