CMX865D2 CML Microcircuits, CMX865D2 Datasheet
CMX865D2
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CMX865D2 Summary of contents
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... CML Microcircuits COMMUNICATION SEMICONDUCTORS D/865/3 November 2005 Features • V.23 1200/75, 1200/1200, 75, 1200 bps FSK • Bell 202 1200/150, 1200/1200, 150, 1200 bps FSK • Bell 103 300/300 bps FSK • Low Voice Falsing DTMF Decoder • DTMF/Tones Transmit and Receive • Low Power - High Performance • ...
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... Performance Specification................................................................... 33 7.1 Electrical Performance ............................................................ 33 7.1.1 7.1.2 7.1.3 7.2 Packaging ................................................................................. always recommended that you check for the latest product datasheet version from the Datasheets page of the CML website: [www.cmlmicro.com]. © 2005 CML Microsystems Plc CONTENTS Absolute Maximum Ratings....................................... 33 Operating Limits ......................................................... 33 Operating Characteristics.......................................... 34 2 CMX865 Page ...
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FSK Modem and DTMF Codec 2. Block Diagram © 2005 CML Microsystems Plc Figure 1 Block Diagram 3 CMX865 D/865/3 ...
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... FSK Modem and DTMF Codec 3. Signal List CMX865D2 Pin No. Name XTALN 1 XTAL/CLOCK 2 RDRVN 12 RXAFB 9 10 RXAN RXA BIAS TXAN 14 TXA 15 CSN 18 COMMAND 19 DATA SERIAL 20 CLOCK REPLY DATA 22 IRQN 23 © 2005 CML Microsystems Plc ...
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FSK Modem and DTMF Codec Notes: I/P = Input O/P = Output BI = Bidirectional T/S = 3-state Output Connection 4. External Components R1 X1 Resistors ±5%, capacitors ±20% unless otherwise stated. Figure 2 Recommended External Components ...
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FSK Modem and DTMF Codec 4.1 Ring Detector Interface Figure 3 shows how the CMX865 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 ...
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FSK Modem and DTMF Codec 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 ringing cycle. The time ...
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FSK Modem and DTMF Codec Resistor R13 is used to match the ac impedance of the interface to the line. With an ideal transformer this resistor would be equal to the desired impedance (e.g. 600Ω); however in practice with a ...
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FSK Modem and DTMF Codec 4-Wire Line Interface Figure 4b shows a simplified interface for use with a 600Ω 4-wire line. The line terminations are provided by R10 and R13, the values of which are dependent on the choice of ...
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FSK Modem and DTMF Codec 5. General Description The CMX865 transmit and receive operating modes are independently programmable. The transmit mode can be set to any one of the following: Bell 103 modem. 300bps FSK. V.23 modem. 1200 or 75bps ...
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FSK Modem and DTMF Codec 5.1 Tx USART A flexible Tx USART is provided for all modem modes. It can be programmed to transmit continuous patterns, Start-Stop characters or Synchronous Data. In both Synchronous Data and Start-Stop modes the data ...
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FSK Modem and DTMF Codec 5.2 FSK Modulator Serial data from the USART is fed to the FSK modulator if V.23, Bell 103 or Bell 202 mode has been selected. The FSK modulator generates one of two frequencies according to ...
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FSK Modem and DTMF Codec 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 ...
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FSK Modem and DTMF Codec 5.7 Rx Modem Filtering and Demodulation When the receive part of the CMX865 is operating as a modem, the received signal is fed to a bandpass filter to attenuate unwanted signals and to provide fixed ...
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FSK Modem and DTMF Codec 5.9 Rx Data Register and USART A flexible Rx USART is provided for all modem modes. It can be programmed to treat the received data bit stream as Synchronous data or as Start-Stop characters. In ...
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FSK Modem and DTMF Codec If the µC has not read the previous data from the Rx Data Register by the time that new data is copied to it from the Rx Data Buffer then the Rx Data Overflow flag ...
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FSK Modem and DTMF Codec © 2005 CML Microsystems Plc Figure 8 C-BUS Transactions 17 CMX865 D/865/3 ...
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FSK Modem and DTMF Codec 5.10.2 General Control Register General Control Register: 16-bit write-only. This register controls general features of the CMX865 such as the Powersave and Loopback modes, the IRQ mask bits and the Relay Drive output. It also ...
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FSK Modem and DTMF Codec General Control Register b8: Powerup This bit controls the internal power supply to most of the internal circuits, including the Xtal oscillator and V BIAS device into Powersave mode ...
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FSK Modem and DTMF Codec 5.10.3 Transmit Mode Register Transmit Mode Register: 16-bit write-only. This register controls the CMX865 transmit signal type and level. All bits of this register are cleared General Reset command, or when ...
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FSK Modem and DTMF Codec Tx Mode Register b7-5: DTMF Twist (Tx DTMF Mode) These three bits allow for adjustment of the DTMF twist to compensate for the frequency response of different external circuits. The device varies the twist by ...
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FSK Modem and DTMF Codec Tx Mode Register b3-0: DTMF/Tones Mode If DTMF/Tones transmit mode has been selected (Tx Mode Register b14-12 = 001), then b7-5 should be set to 000 and b4-0 will select a DTMF signal, a fixed ...
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FSK Modem and DTMF Codec 5.10.4 Receive Mode Register Receive Mode Register: 16-bit write-only. This register controls the CMX865 receive signal type and level. All bits of this register are cleared General Reset command, or when ...
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FSK Modem and DTMF Codec Rx Mode Register b5-3: Rx USART Setting (Rx Modem Modes) These three bits select the Rx USART operating mode ...
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FSK Modem and DTMF Codec 5.10.5 Tx Data Register Tx Data Register: 8-bit write-only Bit: Data bits to be transmitted In Tx Synchronous mode, this register contains the next 8 data bits to be transmitted. b0 ...
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FSK Modem and DTMF Codec 5.10.7 Status Register Status Register: 16-bit read-only. All the bits of this register (except b15-14) are cleared General Reset command, or when b7 (Reset) of the General Control Register is 1. ...
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FSK Modem and DTMF Codec Figure 9a Operation of Status Register b10-5 The IRQN output pin will be pulled low (to V IRQNEN b6 of the General Control Register are both 1. Changes to Status Register bits caused by a ...
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FSK Modem and DTMF Codec ...
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FSK Modem and DTMF Codec 5.10.8 Programming Register Programming Register : 16-bit write-only. This register is used to program the transmit and receive programmed tone pairs by writing appropriate values to RAM locations within the CMX865. Note that these RAM ...
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FSK Modem and DTMF Codec On powerup or after a reset, the tone pairs TA-TC are set to notone, and TD set to generate 2130Hz + 2750Hz at approximately –20dBm each. Receive Tone Pair Programming The programmable tone pair detector ...
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FSK Modem and DTMF Codec The coefficients are entered as 15-bit signed (two’s complement) integer values (the most significant bit of the 16-bit word entered should be zero) calculated as 8192 * coefficient value from the user’s filter design program ...
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FSK Modem and DTMF Codec 6. Application Notes DAA designs, application notes, FAQs and other design resources can be found on the CML website. © 2005 CML Microsystems Plc 32 CMX865 D/865/3 ...
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FSK Modem and DTMF Codec 7. Performance Specification 7.1 Electrical Performance 7.1.1 Absolute Maximum Ratings Exceeding these maximum ratings can result in damage to the device. Supply ( Voltage on any pin ...
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FSK Modem and DTMF Codec 7.1.3 Operating Characteristics For the following conditions unless otherwise specified 3.0V to 3.6V at Tamb = -40 to +85°C, DD Xtal Frequency = 11.0592 or 12.288MHz ± 0.01% (100ppm) 0dBm corresponds to 775mVrms. ...
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FSK Modem and DTMF Codec Transmit Bell 103 FSK Mode Baud rate Mark (logical 1) frequency, high band Space (logical 0) frequency, high band Mark (logical 1) frequency, low band Space (logical 0) frequency, low band Transmit V.23 FSK Mode ...
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FSK Modem and DTMF Codec Transmit Output Level Modem and Single Tone modes DTMF mode, Low Group tones DTMF twist (level of high group tones wrt low group) setting accuracy Tx output buffer gain control accuracy 0 -10 -20 -30 ...
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FSK Modem and DTMF Codec Receive Bell 103 FSK Mode Acceptable baud rate Mark (logical 1) frequency, high band Space (logical 0) frequency, high band Mark (logical 1) frequency, low band Space (logical 0) frequency, low band Receive V.23 FSK ...
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FSK Modem and DTMF Codec Rx Modem Energy Detector Detect threshold (‘Off’ to ‘On) Undetect threshold (‘On’ to ‘Off’) Hysteresis Detect (‘Off’ to ‘On’) response time 300 and 1200baud 150 and 75baud Undetect (‘On’ to ‘Off’) response time 300 and ...
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FSK Modem and DTMF Codec 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 ...
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FSK Modem and DTMF Codec C-BUS Timings (See Figure 13) 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 time HIZ t ...
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... FSK Modem and DTMF Codec 7.2 Packaging Figure 14 24-pin SOIC (D2) Mechanical Outline: Order as part no. CMX865D2 © 2005 CML Microsystems Plc 41 CMX865 D/865/3 ...
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... Fax: +44 (0)1621 875600 Fax: +1 336 744 5054 Sales: Sales: sales@cmlmicro.com us.sales@cmlmicro.com Technical Support: Technical Support: techsupport@cmlmicro.com us.techsupport@cmlmicro.com www.cmlmicro.com www.cmlmicro.com/products/datasheets/download.htm www.cmlmicro.com/products/applications Kallang Pudding Road, #09 to 05/06 Mactech Industrial Building, Singapore 349307 Tel: +65 6745 0426 800 638 5577 Fax: +65 6745 2917 Sales: sg.sales@cmlmicro.com Technical Support: sg ...