HP 83480A User Manual

Increasing Measurement Accuracy
and Time-Interval Measurement
Time-Interval Measurements
Vertical quantization
The A/D converter in the instrument quantizes the waveform into discrete
levels. The resolution of a time measurement cannot be any ner than the
time it takes the input signal to pass through one quantization level (one
LSB). This time will depend on the vertical resolution and the input slew rate.
With a resolution of 8 bits, a vertical scale factor is set to 100 mV/div, and an
input slew rate of 1 V/s, the best timing resolution is 3.13 ms.
Summary
of
dc
errors
Y
ou
can
minimize
the
eects
of
dc
errors
on
time-interval
measurements
by
observing
these
guidelines
when
feasible:

Measure
between
identical
edges|same
slew
rate
, amplitude
,
and
oset.

Use
the
same
dc
level
to
reference each
endpoint
of
the
interval.

Reference
the
measurement
to
the
fastest-slewing
portion of
each edge
.

Operate
the
instrument
in
a
mode
that
gives
the
best
vertical
resolution.
Signal
edges
having
faster
slew
rates
minimize
the
eects
of
dc
errors
on
the
time interval measurement.
9-13

HP 83480A Specifications

General

Brand	HP
Model	83480A
Category	Measuring Instruments
Language	English