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Tutorial
334
Keysight 34970A/34972A User’s Guide
– You can control when the totalizer actually records counts by providing a
gate
signal
(
G
and terminals on the module). A TTL high signal applied to the
“
G
” terminal enables counting and a low signal disables counting. A TTL low
signal applied to the “ ” terminal enables counting and a high signal disables
counting. The totalizer only counts when both terminals are enabled. You can
use either the
G
terminal, the terminal, or both.
When a gate is not
connected, the gate terminal floats to the enabled state, effectively creating a
“gate always” condition.
Totalizer Errors
– Noise on the totalizer input can be a problem, especially on signals with a slow
rise time. This noise can create a false indication of a threshold crossing.
For
more information on cabling noise, see page 268.
– Contact bounce on external switches can create false counts. All mechanical
switches bounce when they open and close. Use an external capacitor to filter
the contact bounce.
G
G
G
Input Signal
(Rising Edge)
Gate Signal
(High True)
Totalizer Input
Add to Total
