m-8888 Clare, Inc., m-8888 Datasheet
m-8888
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m-8888 Summary of contents
Page 1
... Credit card verification Block Diagram DS-M8888-R1 Description The M-8888 is a complete DTMF Transmitter Receiver that features adjustable guard time, auto- matic tone burst mode, call progress mode, and a fully compatible 8051, 8086/8 microprocessor interface. The receiver portion is based on the industry standard ...
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... M-8888 Single-Ended Input Configuration Functional Description M-8888 functions consist of a high-performance DTMF receiver with an internal gain setting amplifier and a DTMF generator that contains a tone burst counter for generating precise tone bursts and paus- es. The call progress mode, when selected, allows the detection of call progress tones ...
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... Guard Time Adjustment: The simple steering circuit shown in the Basic Steering Circuit above is adequate for most applications. Component values are chosen according to the formula: www.clare.com M-8888 (see the Basic Steering Circuit reaches the GTP the steering logic to register the ...
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... IRQ/ result of these frequencies. ). This may be nec- DTMF Generator The DTMF transmitter used in the M-8888 is capable of generating all 16 standard DTMF tone pairs with low distortion and high accuracy. All frequencies are improves talkoff derived from an external 3 ...
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... Error mitter. + 0.30 The M-8888 is initialized on powerup sequence with - 0.49 DTMF mode and burst mode selected. - 0.54 + 0.74 + 0.57 Single-Tone Generation ...
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... DTMF Clock Circuit The internal clock circuit is completed with the addition of a standard 3.579545 MHz television color burst crystal. A number of M-8888 devices can be connect shown in the Common Crystal Connection on page 7 using only one crystal. Control Register B Description ...
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... Interrupt has occurred. Bit one (b1) and/or bit 2 (b2) is set.status register is read. Pause duration has terminated and transmitter is ready for new data. Valid data is in the receive data register. Set on valid detection of the absence of a DTMF signal. www.clare.com M-8888 RD WR Function 1 0 Write to transmitter 0 ...
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... M-8888 Absolute Maximum Ratings Parameter Symbol Power supply voltage ( Voltage on any pin Current on any pin I DD Operating temperature T A Storage temperature T S Note: Exceeding these ratings may cause permanent damage. Functional operation under these conditions is not implied. ...
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... LT t 200 - CL t 180 - DHR DDR DSW DHW OUT www.clare.com M-8888 Max Units +1 dBm 869 mV RMS Nom. - Nom 8 µs - µ ...
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... M-8888 AC Characteristics (Continued) Parameter DTMF Clock Crystal clock frequency Clock input rise time (external clock) Clock input fall time (external clock) Clock input duty cycle (external clock) Capacitive load, OSC2 Voltages referenced to V unless otherwise noted 5.0V ± 5 *Typical values are for use as design aids only and are not guaranteed or subject to production testing. ...
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... Test Loads Timing Diagrams Rev. 1 www.clare.com M-8888 11 ...
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... M-8888 Explanation of Events (A) Tone bursts detected, tone duration invalid, RX Data Register not updated. (B) Tone #n detected, tone duration valid, tone decoded and latched in RX Data Register. (C) End of tone #n detected, tone absent duration valid, RX Data Register remain latched until next valid tone. (D) Tone # detected, tone duration valid, tone decoded and latched in RX Data Register. ...
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... C .008 D .980 E .300 E1 .240 e .100 BSC ec 0° L .115 Inches Min A .093 A1 .004 b .013 D .496 E .291 e .050 BSC H .394 L .016 www.clare.com M-8888 Tolerances Metric (mm) Max Min Max .210 - 5.33 - .38 - .022 .36 .56 .070 1.14 1.78 .014 .20 .36 1.060 24.89 26.92 .325 7.62 8.26 .280 6.10 7.11 2.54 BSC 15° 0° 15° ...
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... Clare’s product may result in direct physical harm, injury, or death to a person or severe property or environmental damage. Clare, Inc. reserves the right to discontinue or make changes to its products at any time without notice. Specification: DS-M8888-R1 ©Copyright 2001, Clare, Inc. ...