FX651 Consumer Microcircuits Limited, FX651 Datasheet
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FX651
Related parts for FX651
FX651 Summary of contents
Page 1
... Transmit an NRZ modulated 18kHz security tone to line. Decode an incoming modulated 18kHz security tone in the presence of high level voice and 12 kHz SPM tones, and provide a logic output. Employing high accuracy switched capacitor filters, the FX651 is protected from crosstalk and false decoding. 1997 Consumer Microcircuits Limited ...
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... SPM and Security Subsystem Section 1.0 Features .......................................................................................................... 1 1.1 Brief Description ............................................................................................ 1 1.2 Block Diagram ................................................................................................ 3 1.3 Signal List ....................................................................................................... 4 1.4 External Components .................................................................................... 6 1.5 General Description ....................................................................................... 7 1.5.1 Overall Function ............................................................................. 7 1.5.2 Description of Blocks .................................................................... 7 1.6 Application Notes........................................................................................... 9 1.6.1 Device Sensitivity ........................................................................... 9 1.6.2 Alias Responses ............................................................................ 9 1.7 Performance Specification.......................................................................... 10 1.7.1 Electrical Performance ................................................................ 10 1.7.2 Packaging ..................................................................................... 14 1997 Consumer Microcircuits Limited CONTENTS 2 FX651 Page D/651/4 ...
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... SPM and Security Subsystem 1.2 Block Diagram V BIAS 1997 Consumer Microcircuits Limited Figure 1 Block Diagram 3 FX651 D/651/4 ...
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... POWER Negative supply rail. O/P A bias line for the internal circuitry, held at ½ also forms the analogue ground for DD the input differential amplifier. This pin must be decoupled by a capacitor mounted close to the device pins (see Figure 1). 4 Description . FX651 D/651/4 ...
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... POWER The positive supply rail. Levels and voltages are dependent upon this supply. This pin should be decoupled to V (see Figure 1). No internal connection: leave open circuit. 5 Description by a capacitor SS FX651 D/651/4 ...
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... R4, C1 and C2) are used to set the gain between -10dB ( 5.0V) and -13dB ( Figure 2 Recommended External Components (D4) 1997 Consumer Microcircuits Limited 3.3V 33pF ±10% 1.1M ±1% 270k ±1% 0.1µF ±20% 51k ±1% 100pF ±10% is 3.3V FX651 5.0V 68pF ±10% 1.0M ±1% 330k ±1% ) voltage. The input DD D/651/4 ...
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... General Description 1.5.1 Overall Function The FX651 is a dual channel tone detector for use in the French Payphone system where 12kHz SPM and 18kHz security tones are used. SPM (12kHz) Detector The SPM detector channel responds to a low level (50mV) 12kHz tone in the presence of a large security tone (16kHz - 20kHz) and speech ...
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... This is a 4th order band pass filter with centre frequency 18kHz. It shapes the modulated digital pulse train from the previous block into a low distortion pulsed sinusoidal waveform. The resulting signal is the system acknowledgement security tone transmitted by the subscriber equipment, via the telephone link, to the local exchange. 1997 Consumer Microcircuits Limited 8 FX651 D/651/4 ...
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... Alias Responses - False Decodes The FX651 is designed to work in telephone systems where certain ranges of input frequencies are expected and other ranges are not. The 12kHz SPM channel works in the presence of speech and a tone in the range 16kHz - 20kHz. The security tone detector functions in the presence of an interfering tone in the range 11kHz - 13kHz ...
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... DD 10 Min. Max. Units -0.3 7 -30 +30 mA -20 +20 mA -55 +125 °C -40 +85 °C 800 mW 13 mW/°C Min. Max. Units 3.0 5.5 V -40 +85 °C 3.579008 3.580082 MHz Min. Typ. Max. 3.3 5.5 2.5 4.0 1.0 2.0 3.5 1.5 4.6 0.4 FX651 Units D/651/4 ...
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... FX651 Max. Units 2 18.18 kHz 2 % 3.7 Vp-p 2.4 Vp-p 100 µ V/V 800 12.18 kHz 11.52 kHz kHz 1 19.08 kHz 16.25 kHz ...
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... The device responds after 8ms of continuous valid tone and de-responds after: a 8ms period of no-tone, tone of 10mV or less out of band tone. 1997 Consumer Microcircuits Limited = 5.0V, -13dB for FX651 = 3.3V. DD D/651/4 ...
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... Transmit Mode. TXOP is modulated by the NRZ DATA pin. An 18kHz toneburst represents logic "0" and "no tone" represents logic "1". Data packets with symbol periods greater than or equal to 6ms can be transmitted. 1997 Consumer Microcircuits Limited Figure 3 System Timing Diagrams 13 FX651 delays D/651/4 ...
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... Rx 12KHz 18KHz Note: Tx Transmit Times include both Response/De-response Times and Rise/Fall Times. 1.7.2 Packaging The FX651 is available in the 16-pin SOIC package detailed below: Figure 4 SOIC Mechanical Outline: Order as part no. FX651D4 1997 Consumer Microcircuits Limited Min Response Delay 40 De-response Delay 40 Response Time De-response Time Transmit " ...
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... Specific testing of all circuit parameters is not necessarily performed. CONSUMER MICROCIRCUITS LIMITED 1 WHEATON ROAD WITHAM - ESSEX CM8 3TD - ENGLAND Telephone: +44 1376 513833 Telefax: +44 1376 518247 e-mail: sales@cmlmicro.co.uk http://www.cmlmicro.co.uk FX651 ...
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... CML Microcircuits Product Prefix Codes Until the latter part of 1996, the differentiator between products manufactured and sold from MXCOM, Inc. and Consumer Microcircuits Limited were denoted by the prefixes MX and FX respectively. These products use the same silicon etc. and today still carry the same prefixes. ...