Features and Functions
3
Keysight 34980A Mainframe User’s Guide
127
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).
The default integration time is 1 PLC.
– 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.
– 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 in seconds (this is called
aperture time
).
Select a value from 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
on page 161) or by setting the ac filter
to the highest frequency limit (see
– The specified integration time is used for all measurements on the selected
channel. If you have applied Mx+B scaling, have assigned alarms to the
selected channel or are using Monitor mode, those measurements are also
made using the specified integration time.
– The following table shows the relationship between integration time,
measurement resolution, number of digits, and number of bits.
– The instrument selects 1 PLC when the measurement function is changed and
after a Factory Reset (
*RST
command). An Instrument Preset (
SYSTem:PRESet
command) or Card Reset (
SYSTem:CPON
command) does
not
change the
integration time setting.
Integration Time
Resolution
Digits
Bits
0.02 PLC
0.2 PLC
1 PLC
2 PLC
10 PLC
20 PLC
100 PLC
200 PLC
< 0.0001 x Range
< 0.00001 x Range
< 0.000003 x Range
< 0.0000022 x Range
< 0.000001 x Range
< 0.0000008 x Range
< 0.0000003 x Range
< 0.00000022 x Range
4½ Digits
5½ Digits
5½ Digits
6½ Digits
6½ Digits
6½ Digits
6½ Digits
6½ Digits
15
18
20
21
24
25
26
26