Section 3: Test subroutine library reference
S530 Parametric Test System Test Subroutine Library User's Manual
3-48
S530-907-01 Rev. A / September 2015
Details
This subroutine provides an appropriate delay time for a current source to reach a specified voltage
by using an equation that accounts for the system capacitance, leakage currents, and number of pins
to which the source is connected. The linear capacitance charging equation used by this subroutine:
IDELAY = 1 ms + ABS(
npin
* CDELAY *
v
) / MAX((ABS(
i
)-ILEAK), ILEAK) * l000 ms
Where:
npin = The number of pins connected to the charging node
CDELAY = A constant representing the capacitance of the system
v = The voltage, in volts
i = The current, in amps
ILEAK = The leakage current
IDELAY = The calculated required delay, in milliseconds
The
kdelay
subroutine defaults to 1 ms for calculated delays less than 1 ms; it defaults to 30 s for
calculated delays greater than 30 s.
Example
kdelay(npin, i, v)
leak
This subroutine measures leakage current of a two-terminal device (diode) at a specified voltage.
Usage
double leak(int
hi
, int
lo
, int
sub
, double
v
, double
ilim
)
hi
Input
The HI pin of the device (anode)
lo
Input
The LO pin of the device (cathode)
sub
Input
The substrate pin of the device
v
Input
The forced voltage, in volts
ilim
Input
The current limit, in amperes
Returns
Output
Measured leakage current:
+4.0E+21 = Measured current is within 98 % of the specified
current limit
Details
This subroutine measures the leakage current by forcing a specified voltage and measuring the
resulting current flow.
If a positive substrate pin is specified, the substrate is grounded. If a positive substrate pin is not
specified, the substrate is left floating.
Source-measure units (SMUs)
SMU1: Forces
v
, programmable current limit, measures current