User`s guide

53220A/53230A User’s Guide 131
53220A/53230A Input Signal Conditioning 4
Using Auto-Level
Automatic setting of the input threshold level is based on the positive and neg-
ative peaks of the input signal. Auto-level is enabled with the command:
INPut[{1|2}]:LEVel[{1|2}]:AUTO {OFF|ON|ONCE}
INPut[{1|2}]:LEVel[{1|2}]:AUTO? (query form)
OFF disables auto-leveling; ON enables auto-leveling. Auto-level ONCE immedi-
ately sets an auto-level and then disables auto-leveling.
When auto-level is enabled, the threshold level is specified as a percentage (%)
of the peak-to-peak input voltage (see “Setting Relative Threshold Levels”).
The CONFigure and MEASure commands enable auto-leveling and set a 50%
threshold level. A reset (*RST) or front panel preset (Preset) also enables
auto-leveling at a 50% threshold level.
Setting Relative Threshold Levels
Relative threshold levels are percentages of the peak-to-peak input signal
amplitude. Relative thresholds are set with the command:
NOTE
If auto-leveling is enabled, querying the absolute level on the current measurement channel
returns the corresponding threshold voltage. If the channel is not the measurement
channel, 9.91E+37 (not a number) is returned. Level2 can only be queried for rise/fall time
and single-channel time interval measurements. Querying Level2 during other
measurement functions returns 9.91E+37 (not a number).