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CMX631A Datasheet, PDF (1/16 Pages) CML Microcircuits – Low Power Operation
CMX631A
Low Voltage
SPM Detector
D/631A/1 May 1998
Features and Applications
• Detects 12kHz or 16kHz SPM
Frequencies
• Tone Follower and Packet Mode
Outputs
• High Speech-Band Rejection
Properties
• Low Power Operation (2.7V <0.8mA)
Provisional Information
• Call Charge Applications on PABX Line
Cards
• Complex and/or Simple Telephone
Systems
• Remote Telephone/Payphones
Brief Description
The CMX631A is a low-power, system-selectable Subscriber Pulse Metering (SPM) detector that indicates
the presence of either 12kHz or 16kHz telephone call-charge frequencies on a telephone line.
Deriving its input directly from the telephone line, input amplitude/sensitivities are component adjustable to
the user's national ‘Must/Must-Not Decode’ specifications via an on-chip input amplifier. The 12kHz and
16kHz frequency limits are accurately defined by the use of an external 3.579545MHz telephone-system
Xtal or clock-pulse input.
The CMX631A demonstrates exceptional 12kHz and 16kHz performance in the presence of both voice and
noise. This device may operate from a single or differential analogue signal input, from which two individual
logic outputs will be produced; a Tone Follower Output and a Packet Mode Output.
This system (12kHz/16kHz) selectable integrated circuit, requires a 2.7V to 5.5V power supply which may be
line-powered, is available in the following packages: 24-pin SSOP (CMX631AD5), 16-pin SOIC
(CMX631AD4), and 16-pin PDIP (CMX631AP3). Additional package styles may be available to meet
specific design requirements.
© 1998 Consumer Microcircuits Limited