MSAN-108 Zarlink Semiconductor, Inc., MSAN-108 Datasheet
MSAN-108
Related parts for MSAN-108
MSAN-108 Summary of contents
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... The first generation receiver typically used LC filters, active filters and/or phase locked loop techniques 925 957 1189 1314 1229 1358 941 1209 1336 MSAN-108 ISSUE 1 June 1983 related and that their This scheme allows for 16 making them somewhat This C ...
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... MSAN-108 HIGH GROUP TONES H1 = 1209 L1 = 697 770 Hz LOW GROUP L3 = 852 Hz TONES L4 = 941 Hz Telephone DTMF keypad matrix. Column H reserved for special signalling. Figure 1b - The Dual Tone Multifrequency (DTMF) Keypad LOOP CURRENT DETECT CIRCUIT MT8870 RECEIVER a) Block diagram of a toll call restrictor. This could be implemented on a small pc board and installed in a telephone to disallow long distance calling ...
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... StD, the output latches, and resets the timing circuit. When St/ its input mode (St function) both Q voltage level at St/GT is compared to the steering threshold voltage V above V TSt MSAN-108 , is a function of the decode DP , which is determined by GTP The Delayed Steering (StD equal to the sum of t ...
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... MSAN-108 A-48 Application Note ...
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... GTA GTP QStD # n t PSrD -Q TO ITS HIGH IMPEDANCE STATE Figure 4 - MT8870 Timing Diagram MSAN-108 GTP raising StD which TSt , ESt is GTP which charges C resetting the 2 . After the DTMF signal is GTA turns off placing St/ TONE ...
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... MSAN-108 Valid tone present indication from DIGITAL DETECT circuit. To OUTPUT LATCHES Simplified steering circuit. Initially ESt is low fully charged applying 0V to St/GT and Q pair ESt is raised turning off Q and allowing C to discharge through R which increases the voltae at St/GT. When VTSt is reached 2 the comparator output goes high indicating a valid signal, latches the outputs and turns on Q pair is lost ESt goes low Q turns off and C charges through R decreasing the voltage at St/GT ...
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... Now that a complete DTMF receiver can be designed with On the other merely a single chip and a few external passive components one can take full advantage of a highly developed signalling scheme as a small, cost- effective signalling solution. MSAN-108 < GTP ...
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... MSAN-108 SOURCE OF DTMF SIGNALS TRANSMISSION MEDIUM INTERFACE Figure 7 - Modular Approach to DTMF Receiver Systems The design of a DTMF receiving system can generally be broken down into three functional blocks (Fig. 7). The first consideration is the interface to the transmission medium. This may be as simple as a few passive components to adequately confi ...
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... 1/ (1/ RC Figure 9 - Differential Input Configuration MSAN-108 chosen as protection, this Transient MT8870 (3) GS (2) ...
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... MSAN-108 Twist is known as the difference in amplitude " " between the low and high group tones specifi as TWIST = 20 log where V is the amplitude of the low frequency tone L and V is the amplitude of the high frequency tone. H Twist is usually caused by the frequency response characteristic of the communication channel ...
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... INTER- CONNECTING LINK COMUNICATIONS LINK REPEATER LOCAL PHONE REPEATER PATCH AUDIO SWITCHING (MT8804 CROSSPOINT SWITCH) MICRO- PROCESSOR CONTROL MT8870 MT5089 DTMF DTMF RECEIVER GENERATOR REPEATER CONTROL SYSTEM MSAN-108 TO MICRO- PROCESSOR BUS USER MOBILE SYSTEM TO TELEPHONE EXCHANGE A-55 ...
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... MSAN-108 A multi-channel repeater system serving a multitude of user groups may be found to achieve its most effective performance in the trunked " case, one RF channel is reserved for system signalling. System operation could be achieved as follows. Each mobile plus the repeater system contain a DTMF receiver, DTMF generator and appropriate control logic ...
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... If non-matching data is received any time during the detection sequence the ”ERROR-“ flip-flop is reset which disables the AND gate until a system ”RESET“ occurs. ”RESET“ may be generated in a variety of ways depending on the MSAN-108 transmit audio MT5089 DTMF ...
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... MSAN-108 MT8870 RECEIVER DTMF SIGNAL SOURCE MT8870 DTMF RECEIVER system design objective. If one DTMF code is reserved exclusively for the ”RESET“ function then the MT8870 outputs can be decoded directly. This requires that the controller send a ”RESET“ command prior to sending an I.D. sequence. ...
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... The computer responds with voice messages generated by a speech synthesizer. In the home, messages to be left are entered via the computer keyboard. Messages to be read may be displayed on the computer monitor or ”played back“ through or unexpected the speech synthesizer. MSAN-108 VALID DIGIT ERROR R Q FLIP- FLOP S ...
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... MSAN-108 MICROPROCESSOR POLLING ALGORITHM CENTRAL CONTROL REMOTE TRANSCEIVER MT8870 DTMF MT5089 RECEIVER DTMF AND I.D. GENERATOR DECODE LOGIC WATER LEVEL MONITOR Polling system for multiple location remote data collection. Figure 17 - DTMF Controlled Data Collection REMOTE DATA COLLECTION MT8870 DATA DTMF LOGGER RECEIVER ...
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... CHARACTERS HENCE HAVE THREE INHERENT "POSITIONS" (POS.1, POS.2, AND POS.3) A PLASTIC OVERLAY CARD ADDS THREE MORE POSITIONS (POS.4, POS.5, AND POS.6) TO KEYS "1" THROUGH "0". * AND # ARE RESERVED EXCLUSIVELY FOR THE SPACE AND RETURN FUNCTIONS. MSAN-108 YOUR HOUSE CONTROL SYSTEM ...
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... MSAN-108 A scheme for coding ASCII characters using one and two digit DTMF signals is outlined in the appendix. Notice that on a telephone keypad keys 2 through 9 are represented by three alpha-characters as well as a numeral. To send an alpha-character, using this scheme, first press the key on which the character ...
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... An auto-dialler containing appropriate phone numbers could be installed at the merchant end as an added time saver. CREDIT CARD COMPANY - AUTO VERIFICATION LINE AUTO MT8870 ANSWER/ LINE DTMF RECEIVER TERMINATION MSAN-108 intercommunication, phone- " conveniences to consumers, CREDIT CARD ACCOUNTING COMPUTER VERIFICATION/ AUTHORIZATION ...
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... MSAN-108 With a similar arrangement, a travelling salesman could access price, delivery and customer status, enter or delete merchandise orders and retrieve messages all from the comfort of the customer’s office (Fig. 23a). A department store could provide shop-by-phone service to its customers using telephone keypad data entry (Fig. 23b). Brokerage fi ...
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... This signalling technique has been applied to a multitude of control and data communications systems. All that is required is a voice quality communication channel with interfacing. The applications are limited only by one’s imagination. designed for appropriate MSAN-108 A-65 ...
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... MSAN-108 Appendix Partial ASCII coding and conversion to 2 sequential DTMF signals ASCII HEX DTMF ACK 06 11 BEL CAN DC1 11 37 DC2 12 38 DC3 13 39 DC4 14 47 DEL 7F 24 DLE ENQ 05 09 EOT 04 08 ESC 1B 14 ...
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North America - West Coast Tel: (858) 675-3400 Fax: (858) 675-3450 Tel: +65 333 6193 Fax: +65 333 6192 Information relating to products and services furnished herein by Zarlink Semiconductor Inc. trading as Zarlink Semiconductor or its subsidiaries (collectively “Zarlink”) ...