M-959 Datasheet, PDF (1/5 Pages) Clare, Inc. – Dial Pulse Counter and Hook Status Monitor

M-959
Dial Pulse Counter and Hook Status Monitor
Features
• Time-guarded dial pulse counting
• 10 or 20 PPS dialing speeds pin selectable
• Tri-state data outputs
• Valid data output strobe
• Data strobe control for use in interrupt-driven
environments
• Independent hook status monitoring
• Low-power CMOS construction
Pin Diagram
Description
The M-959 is a low-power dial pulse counter and
hook status monitor. Contained in a 14-pin package,
the M-959 requires no external components except a
single 3.579 MHz television color burst crystal.
The M-959 is typically connected to a loop current
sensing circuit, which is connected in series with the
voice pair (Tip and Ring) of a telephone line. The M-
959 receives pulses from the loop current sense cir-
cuit and translates them into logic level outputs
indicating hook status and decoded dialed digits.
Logic inputs to the M-959 select dialed digit speeds
and control Data and Strobe outputs supporting bus
interrupt driven implementations.
Ordering Information
Part #
M-959
Description
14-pin plastic DIP
Block Diagram
DS-M959-R3
www.clare.com
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