Keithley 237 - Page 123

17.
At
this
point, the keyed-in parameters can
be
entered
and
saved,
or
canceled. Perform one of the following
steps:
A.
To enter
and
save the keyed-in parameters, press
ENTER The GENERATING SWEEP
message
will
be displayed. Sweep
create
will
disable
and
the Source Measure Unit
will return to the
source-measure display state.
B.
To cancel the keyed-in parameters, press CAN-
CEL.
Sweep
create
will
disable
and
the
Source
Measure
Unit
will
return to the source-measure
display state. The previously programmed
sweep parameters
will
prevail.
NOTE
A log sweep cannot start at
0
or
sweep
through
0.
If
a sweep is programmed to start
at
0,
it
will
default to 1 count on the present
source range.
If
programmed to sweep
through
0,
the message "LOG CANNOT
CROSS
0"
will
be displayed
when
trying to
save the parameters. The sweep
will
be can-
celled.
2.19. 7
Pulse Sweep
Perform the following steps to create a sweep for a pulse
waveform (see Figure
2-34):
1.
Select the desired source (Source
I
Measure
V,
or
Source V
Measure
I)
and
disable autorange (meas-
ure)
if
it is enabled.
2.
Enable sweep create.
3.
Use
the
SELECT
buttons to display the pulse sweep
(as shown below).
PULSE
4.
Press ENTER The last programmed pulse level
will
be displayed. For example,
if
the last programmed
pulse level was
1V,
the following would be dis-
played:
+ 1.0000 V
LEVEL
5.
To change the source value, key-in the value using
the keypad (edit method; see paragraph 2.9.1). For
example, the following shows a keyed-in value of
2.5V.
+2.5
VOLTS
6.
Press ENTER The number
of
pulses in the sweep
will
be displayed. For example,
if
the last pro-
+
+
SECTION2
Operation
grammed number of pulses is
10,
the following
will
be displayed:
0010
NO.
POINTS
7.
To change the number
of
pulses
(0001
to
0500),
key-
in the value using the keypad. The following shows a
keyed-in value of
20
points:
20
NO.
POINTS
Note: Entering a value that exceeds
500
will simply
default to
500.
When the sweep is saved, the message
"BUFFER FILLED"
will
be displayed briefly to indi-
cate
you
tried to enter a value that exceeded
500.
8.
Press ENTER The pulse
on
time will then be dis-
played.
If
the
on
time is presently set to 100msec,
the
following
will
be
displayed:
00.100SEC ONTIME
9.
To change the
on
time
(00.001
to
65.000
seconds),
key-in the value using the keypad. The following
shows a keyed-in value of
200msec:
+.2
SECONDS
10.
Press ENTER The programmed off time will be dis-
played. For example,
if
the off time is presently
1/2
second, the following
will
be displayed:
00.500
SEC
OFF
TIME
11.
To change the off time, key-in the time value using
the keypad. The following shows a keyed-in value of
300msec:
+.3
SECONDS
12.
Press ENTER The bias level
will
then be displayed.
For example,
if
the bias is presently set to
OV,
the fol-
lowing will be displayed:
+0.0000
V
BIAS
13.
To change the bias level, key-in the value from the
keypad. The following shows a keyed-in bias level of
-1.25V:
-1.25
VOLTS
14.
Press ENTER The currently selected source range
will be displayed. For example,
if
110V
range is cur-
rently selected, the following
will
be
displayed:
2-71