CMX631A Overview
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 ponent adjustable to the user's national ‘Must/Must-Not Decode’ specifications via an on-chip input amplifier. The 12kHz and 16kHz...