Keithley 237

SECTION3
IEEE-488 Reference
Programming
Notes
3-54
+
Volts
e ~
I i
~Delay-+ +Delay~~
6
r------,+-Stop
4
2
Start-+r------,
05, 2. 5, 0, 2, 100, 70
Sweep Source
ION iloFF
1
2V 100msec
2 ov
70msec
3
3.17V 100msec
4 ov
70msec
5
5V
100msec
6
ov 70msec
Figure 3-11. Logarithmic Stair Pulsed Sweep Waveform
Appending Sweeps
Q6- Append fixed level sweep
Q7- Append linear stair sweep
QB- Append logarithmic stair sweep
Q9- Append fixed level pulsed sweep
QlO- Append linear stair pulsed sweep
Qll -Append logarithmic stair pulsed sweep
Existing sweeps can be appended with another sweep
or sweeps until the buffer is
filled. The only restriction is that you cannot mix non-pulsed sweeps with pulsed
sweeps. For example,
if a linear stair sweep is in the buffer, only a fixed level sweep,
linear stair sweep,
or log stair sweep can be appended to it, not a pulsed sweep.
Two linear stair pulsed sweeps are appended in the second programming example.
1. If the bias and sweep ranges are not programmed to autorange, the same fixed
range should be selected to prevent range changes during a sweep. Range
changes affect sweep timing and, since the
output level is momentarily set to zero
during a range change, there could be
an undesirable effect on the test in pro-
gress.
2. In autorange, the source range is adjusted for the highest on-scale sourcing pos-
sible.
+