Keithley 237 - Page 122

SECTION2
Operation
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.
2.19.6 Logarithmic Staircase
Sweep
Perform the following steps to create a sweep for a loga-
rithmic staircase waveform (see Figure
2-33):
1.
Select
the desired source (Source I Measure
V,
or
Source
V Measure
I).
2.
Enable sweep create.
3.
Use
the
SELECT
buttons to display the log staircase
sweep (as shown below).
LOG
STAIR
4.
Press ENTER The last programmed source start
value
will
be displayed. For example,
if
the last
pro-
grammed start value was 1
V,
the following would be
displayed: ·
+l.OOOOV
START
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 source level
at
which the sweep
will
STOP
is displayed. For example
if
the last pro-
grammed stop value is
100V,
the following
will
be
displayed:
+100.00V STOP
7.
To change the stop value, key-in the value using the
keypad. The following shows a keyed-in value of
20V:
+20
VOLTS
8.
Press ENTER
POINTS/DECADE
will then be dis-
played.
If,
for example, five source-measure points
per
decade is currently selected, the following
will
be displayed:
2-70
+
+
5 POINTS/DECADE
9.
To select
an
alternate points
per
decade value
(5,
10,
25
or
50),
use the
SELECT
buttons to display the de-
sired value. The following shows a selection of
50
source-measure points
per
decade:
50 POINTS/DECADE
10.
Press ENTER The delay
will
then be displayed.
If
the delay is presently set to
1/2
second, the following
will
be displayed:
00.500
SEC
DELAY
11.
To change the time delay
(00.001
to 65.000
seconds),
key-in the value using the keypad. The following
shows a keyed-in value of one second:
1
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
autorange is cur-
rently selected, the following
will
be displayed:
AUTO
RANGE
15.
Tochangethesourcerange, usetheSELECTbuttons
to display the desired range. The following shows
the
11
V
range selected:
ll.OOOV
RANGE
Note: Selecting a fixed range that is lower than the
highest keyed-in source
or
bias value
will
result in
the message
"VALUE OUT OF
RANGE"
when
the
parameters are saved.
In
this situation, the source
will
default to
BEST
FIXED
range.
16.
Press ENTER The following message
will
be dis-
played:
SAVE?
ENTER/CANCEL