Agilent Technologies Switch/Measure manual Custom A/D Integration Time

Features and Functions 2

The following command selects the 1 A range with 6½ digits of resolution on channel 2041 (current measurements are allowed only on channels 41 through 44 on the 34921A).

MEAS:CURR:AC? 1,1E-6,(@2041)

You can also select the resolution using the SENSe commands. For example, the following command specifies a 2- wire ohms measurement with 100Ω of resolution on channel 1003.

SENS:RES:RES 100,(@1003)

Custom A/D Integration Time

Integration time is the period of time the internal DMM’s analog- to- digital (A/D) converter samples the input signal for a measurement. Integration time affects the measurement resolution (for better resolution, use a longer integration time) and measurement speed (for faster measurements, use a shorter integration time).

•Integration time is specified in number of power line cycles (PLCs). Select from 0.02, 0.2, 1, 2, 10, 20, 100, or 200 power line cycles. The default is 1 PLC.

•Only integral number of power line cycles (1, 2, 10, 20, 100, or 200 PLCs) provide normal mode (line frequency noise) rejection.

•You can also specify integration time directly in seconds (this is called aperture time). Select a value between 300 µs and 1 second, with

4 µs resolution.

•The only way to control the reading rate for ac measurements is by changing the channel delay (see “Channel Delay” on page 53) or by setting the ac filter to the highest frequency limit (see “AC Low Frequency Filter” on page 36).

•The specified integration time is used for all measurements on the selected channel. If you have applied Mx+B scaling or have assigned alarms to the selected channel, those measurements are also made using the specified integration time. Measurements taken during the Monitor function also use the specified integration time.

34980A User’s Guide 19