Square Wave Capacitance Measurements; Staircasemeasurements - Keithley 595 Instruction Manual

IEEE-488
PROGRAMMING
4.10 PROGRAMMING EXAMPLES
PROGRAM
The following programs demonstrate how to make
capacitancewtd current measurements over the bus using
the HP-85 computer as a controller.
4.10.1 Square Wave Capacitance
Measurements
Enter the following statements into the computer to make
square wave capacitance measurements:
40 OUTFUT 7ZSj i s l.lOX' s
Turn voltage source
off.
5M ~JCITFIJT ~7% i
Defme measurement
6 i &2;z:s3I iHE%' r
parameters.
in IQUTFIJT 728; L rLliXs '
2
Set voltage source for
DC output.
7Q WAIT 3308
Let device under test
settle at -2V for 2sec.
PROGRAM
COMMENTS
Send remote
enable.
BE1 OUTPUT
738.: i~ rZBXW3X" I Disable zero check
and set voltage source
for staircase output.
90 S=SFl:lLL1728;~
Serial poll 595 until
staircase~starts.
40 OLITFIJT
iZS; c i l.l@X' '
Set voltage sources
off.
5Q 0LlTFU-j TEE:; 6 s U5S31 .5X
Defines measure-
cm:' 3
ment parameters.
CE1UUTFlJT728;r'Z13X~'
Release zero check.
713 ENTER i'z4; R$
-c
Receive reading
over bus.
8M DISP A%
Display reading on
computer.
90 GOTlU 78
Repeats cycle of
readings.
1QQ END
120 IF EITISI~)=I THEM 1CB
130 ENTER :?E:.$,$
Send reading to
computer.
140 DISF A*
Display reading on
150 GOTO 110~
CRT of computer.
Loop back to line 110.
160 END
"To measure current, add Fl to the command string in line
50.
Press the RUN key to run the program: Line 30 will place
the instrument in the capacitance function with zero check
enabled (default conditions). Lime 40 will turn the voltage
source off. Line 50 will set the voltage source fork 5V in
square wave, step voltage for 1OOmV and delay time for 0.5
seconds. Lime 60 releases zero check. Lines 70 and 80
receive and display a capacitance reading on the computer.
Lime 90 repeats the cycle.
Press the RUN key to run the program. Line 40 will turn
the voltage source off. Line 50 will set the bias voltage to
OV, step voltage to lOOmV, delay time to one second and
the high limit to 2V. Line 60 will set voltage source for a
DC output. Line 79 allows a couple of seconds for the
device under test to settle. Line 80 will disable zero check
and set the output for a staircase output. Lines 90 and 100
will serial poll the instrument until the staircase starts. Lines
110 through I50 will send and display each capacitance
measurementand stop at the end of the staircase.
4.10.2 Staircase Measurements
NOTES:
Enter the following statements into the computer to make
staircase measurements:
1. Make sure unit is not set to staircase when sending the
V command, since the voltage source will go to "DC'
at a step above the voltage values.
2. When terminating a staircase measurement, the voltage
out will go to the next voltage source step;
COMMENTS
Place 595 in remote.
Set 595 to default
conditions.
4-48