Keithley S530 - Vbes

Section 3: Test subroutine library reference S530 Parametric Test System Test Subroutine Library User's Manual
3-62 S530-907-01 Rev. A / September 2015
vbes
This subroutine measures base-emitter voltage of a bipolar transistor.
Usage
double vbes(int e, int b, int c, int sub, double ipgm, char type)
e
Input
The emitter pin of the device
b
Input
The base pin of the device
c
Input
The collector pin of the device
sub
Input
The substrate pin of the device
ipgm
Input
The forced current, in amperes
type
Input
Type of transistor: "N" or "P"
Returns
Output
-1.0 = Type not specified as "N" or "P"
+2.0E+21 = Voltage limit reached; measured voltage is within 98 % of
the 3 V limit
Details
For a PNP transistor, this subroutine measures the base-emitter voltage at a specified emitter current
with the base and collector terminals tied to ground.
For an NPN transistor, this subroutine measures the emitter-base voltage at a specified base current
with the emitter and collector terminals tied to ground.
If a positive substrate pin is specified, the substrate is grounded. If a positive substrate pin is not
specified, the substrate is left floating.
A delay is incorporated into the vbes subroutine; this delay is calculated time required for stable
forcing of ipgm with a 3 V voltage limit.
V/I polarities
The polarity of ipgm is determined by device type.
Source-measure units (SMUs)
 SMU1: Forces ipgm, 3 V voltage limit, measures vbes