[sdiy] can someone explain latches?

HARRY BISSELL harrybissell at wowway.com
Thu May 7 01:25:55 CEST 2009

A "type D register" is like a digital S/H
The "transparent latch" is like a digital T/H (track / hold)
H^) harry

----- Original Message -----
From: David G. Dixon <dixon at interchange.ubc.ca>
To: 'Dan Snazelle' <subjectivity at hotmail.com>, synth-diy at dropmix.xs4all.nl
Sent: Wed, 6 May 2009 18:21:38 -0400 (EDT)
Subject: RE: [sdiy] can someone explain latches?


A "latch" is really just a transparent flip-flop.  Quoting Horowitz and

The term "latch" is usually reserved for a special kind of register: one in
which the outputs follow the inputs when enabled and hold the last value
when disabled.  Since the label "latch" has become ambiguous with use, the
terms "transparent latch" and "type D register" are often used to
distinguish these closely related devices."

Hence, a latch will follow the data input whenever it is enabled.  A
register follows the data input only on the transition of a clock pulse.

Synth-diy mailing list
Synth-diy at dropmix.xs4all.nl

More information about the Synth-diy mailing list