Keysight Technologies N6700 - Page 39

Installation 2
Keysight N6700 User’s Guide 39
The following figure shows the paralleled connections for N678xA SMU
power modules. Note that remote sensing is not normally used in
Current Priority mode.
Grouping the Outputs
Once outputs have been connected in parallel, they can be configured or
“grouped” to act as a single, higher-power channel. This applies when
programming via the front panel or using SCPI commands. How to
group output channels that have been connected in parallel is discussed
in Chapter 4 under “System-Related Operations”. The output grouping
function is not available for N678xA SMU power modules.
If you are not grouping output channels, first program both outputs to
the desired output voltage. Then program the current limit of each
output. In Current Priority mode, program the output current of each
output to one half of the total desired output current. Set the voltage
limit to a value higher than the expected output voltage.
Effect on Specifications
Specifications for outputs operating in parallel can be obtained from the
specifications for single outputs. Most specifications are expressed as a
constant or as a percentage (or ppm) plus a constant. For parallel
operation, the percentage portion remains unchanged while constant
portions or any constants are changed as indicated below. For current
readback accuracy and temperature coefficient of current readback, use
the minus current specifications:
Current
All parallel specifications referring to current are twice the single output
specification except for programming resolution, which is the same for bot
h
single output and parallel output operation.
Voltage
All parallel specifications referring to voltage are the same as for a single
output except for CV load effect, CV load cross regulation, CV source effect,
and CV short term drift. These are all twice
the voltage programming accuracy
(including the percentage portion) at all operating points.
Load Transient
Recovery Time
Load transient specifications are typically twice the single output.
OUTPUT 2 OUTPUT 1
TWIST LEADS
LOAD
+
SENSE JUMPERS
INSTALLED FOR
LOCAL SENSING
− − G + + +S G -S − − G + + +S G -S