FX613

The FX613 is a wide-band, 'N-Tone', non-predictive tone decoder to measure telephone system call progress tones in PABX, Pay/Feature-Phone, Fax and Modem systems.

Adhering to Must/Must-Not Decode limits and able to measure inband frequencies in outband modulation, FX613 measures the frequency of input signals in the range 300Hz to 2,150Hz; the result of each measurement is presented to a system Processor, as a 6-bit serial word.

The FX613 frequency range, which covers the World's call progress application spectrum, is processed internally as two bands: LO = 300Hz to 660Hz and HI = 900Hz to 2150Hz. Frequency measurement is achieved by counting the number of cycles in a set time period (LO = 39.47ms or HI = 13.16ms). Bad signal/level quality or NOTONE results in a count-abort, timing-reset and no output from the decoder.

Current frequency information is output for the Processor using a Serial Data, Clock and Interrupt interface.

Data from the FX613 should be processed by a Processor whose algorithms are able to recognize the frequency, sequence and/or cadence of input signals as national call progress information; e.g.: 'Dial', 'Busy','Number-Unobtainable', 'Ringing' and automatic tones employed by Fax, Modem systems. Software can be simply configured to reject speech frequencies. Due to its 'N-Tone', non-predictive decoding capability,units employing the FX613 can be redeployed under a new national standard by a simple software amendment.Available in 16-pin plastic S.O.I.C. SMD and 14-pin plastic DIL packages, this low-cost, mixed analogue/digital microcircuit has a typical power requirement of less than 1mA at 3 volts and utilizes a telecom-system clock input of 3.579545MHz to maintain frequency accuracy.