Measurement Setups - Keysight Technologies N6705C Operating And Service Manual

8 Verification and Calibration

Measurement Setups

Voltmeter
To ensure that the values read by the voltmeter during both the verification procedure and the
calibration procedure are not affected by the instantaneous measurement of the AC peaks of the
output current ripple, make several DC measurements and average them. You can set up the
voltmeter to do this automatically by programming 100 power line cycles per measurement.
If you are using a Keysight 3458A DMM, turn on auto-calibration (ACAL) and autorange (ARANGE).
Perform auto-calibration every 24 hours when verifying or calibrating models N678xA SMU.
Current Monitoring Shunt
The 4-terminal current shunt is used to make accurate current measurements. It has two monitoring
terminals as well as two load terminals. Connect the voltmeter directly to the monitoring terminals.
Also allow sufficient airflow for cooling.
Electronic Load
Many of the test procedures require the use of a variable load capable of dissipating the required
power. If a variable resistor is used, switches should be used to connect, disconnect, or short the load
resistor. For most tests, an electronic load can be used. The electronic load is considerably easier to
use than load resistors, but it may not be fast enough to test transient recovery time and may be too
noisy for the noise (PARD) tests. Fixed load resistors may be used in place of a variable load, with
minor changes to the test procedures.
Note that an N6784A SMU power module should be used as the load when testing transient response
on models N678xA SMU and N6783A.
Front Panel Connections
Except for Test Setup A, do not connect anything to the Sense terminals. Check the front panel 4 wire
LED to see whether 4 wire sensing is enabled (LED is lit) or disabled (LED not lit). To change the 4 wire
sense settings, press [Settings], then navigate to and select Advanced. Under Sense, select Local or 4
Wire sensing. Connect all leads to the output terminals as shown in the following figure.
Program Control
You may chose to automate the calibration and verification procedures. If computer controlled test
setups are used, the relatively slow settling times and slew rates of the power analyzer must be taken
into account. Use "Wait" statements to allow for the appropriate settling times for the power analyzer.
Keysight N6705C Operating and Service Guide 373