Section 9: Keithley External Control Interface (KXCI)
Model 4200A-SCS Parameter Analyzer Reference Manual
9-14
4200A-901-01 Rev. C / February 2017
CH
This command defines a SMU channel.
Usage
CH
A
, '
BBBBBB
', '
CCCCCC
',
D
,
E
A
1
,
2
, ... or
n
SMU channel number; the largest value of
n
is the number of channels in
the system (9 maximum); if no parameters are specified after the channel number,
the channel is turned off
BBBBBB
Voltage name
CCCCCC
Current name
D
Source mode or common:
•
1
: Voltage source mode
•
2
: Current source mode
•
3
: Common (output high connected to common)
E
Source function:
•
1
: VAR1 sweep source function
•
2
: VAR2 step source function
•
3
: Constant (fixed) source function
•
4
: VAR1' source function
Details
For every used channel that is configured as a SMU, you must specify names for voltage and current,
select the source mode (voltage, current, or common), and select the source function (VAR1, VAR2,
constant, or VAR1').
When the source mode (
D
) is set to common (
3
), the source function (
E
) must be set to constant (
3
).
The VAR1 source function performs a linear or logarithmic sweep. The VAR1 function performs a
sweep that is synchronized to the steps of VAR2. The VAR1 sweep is performed whenever VAR2
goes to a new step value. The constant source function outputs a fixed (constant) source value.
The VAR1' source function is similar to the VAR1 function, except that each sweep step is scaled by
the Ratio value (RT) and an Offset (FS) as follows:
VAR1' sweep step = (VAR1 sweep step
×
RT) + FS
For example, assume VAR1 is set to sweep from +1 V to +3 V using 1 V steps. If Ratio (RT) is set to
2, and Offset (FS) is set to 1, each step of VAR1' is calculated as follows:
VAR1' step 1 = (1 V
×
2) + 1 = 3 V
VAR1' step 2 = (2 V
×
2) + 1 = 5 V
VAR1' step 3 = (3 V
×
2) + 1 = 7 V
To disable a channel, send:
CH
x
Where
x
= 1 to 9
Example 1
CH3, 'V1', 'I1', 1, 3
This command string sets up the SMU assigned to channel 3 to source a fixed voltage (1 V). The specified
names for voltage and current are
V1
and
I1
, respectively.
