CMX867D2 CML Microcircuits, CMX867D2 Datasheet
CMX867D2
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CMX867D2 Summary of contents
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D/867/2 November 2001 Features V.22, Bell 212A 1200/1200 or 600/600 bps DPSK V.23 1200/75, 1200/1200, 75, 1200 bps FSK Bell 202 1200/150, 1200/1200, 150, 1200 bps FSK V.21 or Bell 103 300/300 bps FSK DTMF/Tones Transmit and Receive ‘Powersave’ Standby ...
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Low Power V.22 Modem Section 1.1 Brief Description.................................................................................. 1 1.2 Block Diagram ..................................................................................... 3 1.3 Signal List ............................................................................................ 4 1.4 External Components.......................................................................... 5 1.4.1 Ring Detector Interface........................................................... 6 1.4.2 Line Interface........................................................................... 7 1.5 General Description............................................................................. 9 1.5.1 Tx USART .............................................................................. ...
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Low Power V.22 Modem 1.2 Block Diagram 2001 Consumer Microcircuits Limited Figure 1 Block Diagram 3 CMX867 D/867/2 ...
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Low Power V.22 Modem 1.3 Signal List CMX867 D2/E2/P4 Pin No. Name 1 XTALN XTAL/CLOCK 2 RDRVN 12 RXAFB 9 RXAN 10 RXA 11 ...
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Low Power V.22 Modem Notes: I/P = Input O/P = Output BI = Bidirectional T/S = 3-state Output Connection 1.4 External Components R1 X1 Resistors 5%, capacitors 20% unless otherwise stated. Figure 2 Recommended External Components for ...
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Low Power V.22 Modem 1.4.1 Ring Detector Interface Figure 3 shows how the CMX867 may be used to detect the large amplitude Ringing signal voltage present on the 2-wire line at the start of an incoming telephone call. The ring ...
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Low Power V.22 Modem If the time constant of R24 and C22 is large enough then the voltage on RT will remain below the threshold of the 'B' Schmitt trigger for the duration of a ring cycle. The time for ...
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Low Power V.22 Modem The transmit line signal level is determined by the voltage swing between the TXA and TXAN pins, less 6dB due to the line termination resistor R13, and less the loss in the line coupling transformer. Allowing ...
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Low Power V.22 Modem 1.5 General Description The CMX867 transmit and receive operating modes are independently programmable. The transmit mode can be set to any one of the following: V.22 and Bell 212A modem. 1200 or 600 bps DPSK (Differential ...
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Low Power V.22 Modem 1.5.1 Tx USART A flexible Tx USART is provided for all modem modes, meeting the requirements of V.14 for DPSK modems. It can be programmed to transmit continuous patterns, Start-Stop characters or Synchronous Data. In both ...
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Low Power V.22 Modem In all modes the transmitted bit and baud rates are the nominal rates for the selected modem type, with an accuracy determined by the XTAL frequency accuracy, however for DPSK modes V.14 requires that Start-Stop characters ...
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Low Power V.22 Modem 1.5.3 Tx Filter and Equaliser The FSK or DPSK modulator output signal is fed through the Transmit Filter and Equaliser block which limits the out-of-band signal energy to acceptable limits. In 600 and 1200 bps FSK ...
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Low Power V.22 Modem 1.5.6 Rx DTMF/Tones Detectors In Rx Tones Detect mode the received signal, after passing through the Rx Gain Control block, is fed to the DTMF / Tones / Call Progress / Answer Tone detector. The user ...
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Low Power V.22 Modem 1.5.7 Rx Modem Filterering and Demodulation When the receive part of the CMX867 is operating as a modem, the received signal is fed to a bandpass filter to attenuate unwanted signals and to provide fixed compromise ...
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Low Power V.22 Modem The FSK demodulator recognises individual frequencies as representing received ‘1’ or ‘0’ data bits: The DPSK demodulator decodes DPSK modulation of a 1200Hz or 2400Hz carrier and is used for V.22 and Bell 212A modes. It ...
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Low Power V.22 Modem Whenever a new character is copied into the C-BUS Rx Data Register, the Rx Data Ready flag bit of the Status Register is set to ‘1’ to prompt the µC to read the new data and, ...
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Low Power V.22 Modem In order that received Break signals can be handled correctly in V.14 Rx overspeed mode, a received character which has all bits ‘0’, including the Stop and any Parity bits, will always cause the Rx Framing ...
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Low Power V.22 Modem 2001 Consumer Microcircuits Limited Figure 8 C-BUS Transactions 18 CMX867 D/867/2 ...
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Low Power V.22 Modem 1.5.10.2 General Control Register General Control Register: 16-bit write-only. C-BUS address $E0 This register controls general features of the CMX867 such as the Powersave and Loopback modes, the IRQ mask bits and the Relay Drive output. ...
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Low Power V.22 Modem General Control Register b8: Powerup This bit controls the internal power supply to most of the internal circuits, including the Xtal oscillator and V supply. Note that the General Reset command clears this bit, putting the ...
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Low Power V.22 Modem 1.5.10.3 Transmit Mode Register Transmit Mode Register: 16-bit write-only. This register controls the CMX867 transmit signal type and level. All bits of this register are cleared General Reset command, in Powersave mode, ...
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Low Power V.22 Modem Tx Mode Register b8-7: Tx Guard tone (DPSK modes) These 2 bits select the guard tone to be transmitted together with highband DPSK. Set both bits FSK modes ...
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Low Power V.22 Modem Tx Mode Register b8-0: DTMF/Tones mode If DTMF/Tones transmit mode has been selected (Tx Mode Register b15-12 = 0001) then b8-5 should be set to 0000 and b4-0 will select a DTMF signal or a fixed ...
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Low Power V.22 Modem 1.5.10.4 Receive Mode Register Receive Mode Register: 16-bit write-only. This register controls the CMX867 receive signal type and level. All bits of this register are cleared General Reset command, in Powersave mode ...
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Low Power V.22 Modem Rx Mode Register b8: Rx Auto-equalise (DPSK modes) This bit controls the operation of the receive DPSK auto-equaliser. Set FSK modes Mode Register b7-6: Rx Scrambler ...
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Low Power V.22 Modem 1.5.10.5 Tx Data Register Tx Data Register: 8-bit write-only. Bit Data bits to be transmitted In Synchronous Tx data mode this register contains the next 8 data bits to be transmitted. Bit ...
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Low Power V.22 Modem 1.5.10.7 Status Register Status Register: 16-bit read-only. Bits 15 and 13-0 of this register are cleared General Reset command, in Powersave mode, or when b7 (Reset) of the General Control Register is ...
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Low Power V.22 Modem Notes: ** This column shows the corresponding IRQ Mask bits in the General Control Register transition on any of the Status Register bits 14-5 will cause the IRQ bit b15 to be ...
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Low Power V.22 Modem In DPSK Rx modem modes b2-0 of the Status Register contain a value indicative of the received signal BER, see Figure 10 FSK modem modes bits 2 and 1 will be zero and b0 ...
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Low Power V.22 Modem 1.E-03 1.E-04 BER 1.E-05 1.E-06 0 Figure 10 Typical Rx BER vs. Average Status Register BER Reading (b2-0) 1.5.10.8 Programming Register Programming Register : 16-bit write-only. This register is used to program the transmit and receive ...
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Low Power V.22 Modem Programming is done by writing a sequence seventeen 16-bit words to the Programming Register. The first word should be 32768 (8000 hex), the following 16-bit words set the frequencies and levels and are ...
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Low Power V.22 Modem Programming is done by writing a sequence of twenty-seven 16-bit words to the Programming Register. The first word should be 32769 (8001 hex), the following twenty-six 16-bit words set the frequencies and levels and are in ...
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Low Power V.22 Modem Note that if any changes are made to the programmed values while the CMX867 is running in Programmed Tone Detect mode they will not take effect until the CMX867 is next switched into Programmed Tone Detect ...
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Low Power V.22 Modem 1.6 Application Notes 1.6.1 V.22 Calling Modem Application This section describes how the CMX867 can be used in a V.22 Calling modem application, employing V.25 automatic answering and the V.22 recommended handshake sequence. This attempts to ...
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Low Power V.22 Modem 1.6.2 V.22 Answering Modem Application This section describes how the CMX867 can be used in a V.22 Answering modem application, employing V.25 automatic answering and the V.22 recommended handshake sequence. This attempts to establish a 1200 ...
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Low Power V.22 Modem 1.7 Performance Specification 1.7.1 Electrical Performance 1.7.1.1 Absolute Maximum Ratings Exceeding these maximum ratings can result in damage to the device. Supply ( Voltage on any pin Current ...
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Low Power V.22 Modem 1.7.1.3 Operating Characteristics For the following conditions unless otherwise specified 2.7V to 5.5V at Tamb = -40 to +85°C, DD Xtal Frequency = 11.0592 or 12.288MHz 0dBm corresponds to 775mVrms. DC Parameters I (Powersave ...
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Low Power V.22 Modem Transmit DPSK Modes (V.22 and Bell 212A) Carrier frequency, high band Carrier frequency, low band Baud rate Bit rate 550Hz guard tone frequency 550Hz guard tone level wrt data signal 1800Hz guard tone frequency 1800Hz guard ...
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Low Power V.22 Modem Transmit Output Level Modem and Single Tone modes DTMF mode, Low Group tones DTMF: level of High Group tones wrt Low Group Tx output buffer gain control accuracy 0 -10 -20 -30 dBm -40 -50 -60 ...
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Low Power V.22 Modem Receive DPSK Modes (V.22 and Bell 212A) Carrier frequency (high band) Carrier frequency (low band) Baud rate Bit rate Receive V.21 FSK Mode Acceptable baud rate Mark (logical 1) frequency, high band Space (logical 0) frequency, ...
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Low Power V.22 Modem Rx Modem '0011' Dibit Pattern Detector (1200bps DPSK mode) Will detect pattern lasting for Will not detect pattern lasting for Hold time (minimum detector ‘On’ time) Rx Modem Energy Detector Detect threshold (‘Off’ to ‘On) Undetect ...
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Low Power V.22 Modem DTMF Decoder Valid input signal levels (each tone of composite signal) Not decode level (either tone of composite signal) Twist = High Tone/Low Tone Frequency Detect Bandwidth Frequency Not Detect Bandwidth Max level of low frequency ...
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Low Power V.22 Modem C-BUS Timings (See Figure 14) t CSN-Enable to Clock-High time CSE t Last Clock-High to CSN-High time CSH t Clock-Low to Reply Output enable LOZ time t CSN-High to Reply Output 3-state HIZ time t CSN-High ...
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... Low Power V.22 Modem 1.7.2 Packaging Figure 15a 24-pin SOIC (D2) Mechanical Outline: Order as part no. CMX867D2 Figure 15b 24-pin TSSOP (E2) Mechanical Outline: Order as part no. CMX867E2 2001 Consumer Microcircuits Limited 44 CMX867 D/867/2 ...
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Low Power V.22 Modem Figure 15c 24-pin DIL (P4) Mechanical Outline: Order as part no. CMX867P4 Handling precautions: This product includes input protection, however, precautions should be taken to prevent device damage from electro-static discharge. CML does not assume any ...