CMX868D2 Consumer Microcircuits Limited, CMX868D2 Datasheet
CMX868D2
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CMX868D2 Summary of contents
Page 1
... Powersave mode, providing an interrupt which can be used to wake up the host µController when line voltage reversal or ringing is detected. The CMX868 operates from a single 2.7 to 5.5V supply over a temperature range of -40°C to +85°C and is available in 24-pin TSSOP, SOIC and DIP packages. 2002 Consumer Microcircuits Limited CMX868 Low Power V.22 bis Modem ...
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... Reference Diagrams.............................................................. 36 1.7 Performance Specification................................................................ 37 1.7.1 Electrical Performance.......................................................... 37 1.7.1.1 Absolute Maximum Ratings..................................... 37 1.7.1.2 Operating Limits....................................................... 37 1.7.1.3 Operating Characteristics ........................................ 38 1.7.2 Packaging.............................................................................. 45 2002 Consumer Microcircuits Limited CONTENTS General Reset Command.............................. 17 General Control Register.............................. 19 Transmit Mode Register ............................... 21 Receive Mode Register ................................. 24 Tx Data Register............................................ 26 Rx Data Register ........................................... 26 Status Register.............................................. 27 Programming Register.................................. 30 ...
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... Low Power V.22 bis Modem 1.2 Block Diagram 2002 Consumer Microcircuits Limited Figure 1 Block Diagram 3 CMX868 D/868/6 ...
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... COMMAND 19 DATA SERIAL 20 CLOCK REPLY DATA 22 IRQN 23 2002 Consumer Microcircuits Limited Signal Type O/P The output of the on-chip Xtal oscillator inverter. I/P The input to the oscillator inverter from the Xtal circuit or external clock source. O/P Relay drive output, low resistance pull down to V when active and medium resistance pull up ...
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... V The V connections to the Xtal oscillator capacitors C1 and C2 should also be low impedance and SS preferably be part of the V ground plane to ensure reliable start up of the oscillator. SS 2002 Consumer Microcircuits Limited 100k 11.0592MHz or 12.288MHz pins and the C1, C2 ...
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... With R20-22 all 470k as Figure 3, then setting R23 to 68k of 40Vrms and above for V DD R20, 21, 22 R23 R24 Figure 3 Ring Signal Detector Interface Circuit 2002 Consumer Microcircuits Limited over the range 3 to 5V. C20, 21 470k See text C22 D1-4 470k Resistors 5%, capacitors 20% ...
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... For clarity the 2-wire line protection circuits have not been shown. R11 See text R12 100k R13 600 2002 Consumer Microcircuits Limited towards exp(-t/(R24 x C22 and 0.33 F) give a minimum RT charge time of 2-wire line ...
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... Transmit and receive line level settings and the value of R11 are as for the 2-wire circuit. R10, 13 600 R11 See text R12 100k 2002 Consumer Microcircuits Limited 4-wire line. The line terminations are provided C3 C11 C12 Resistors 5%, capacitors 20% Figure 4b 4-Wire Line Interface Circuit ...
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... Call progress signal detect. User programmed tone or tone pair detect. Disabled. The CMX868 may also be set into a Powersave mode which disables all circuitry except for the C-BUS interface and the Ring Detector. 2002 Consumer Microcircuits Limited 9 CMX868 D/868/6 ...
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... Buffer transfer then the Status Register Tx Data Underflow bit will be set this event the contents of the Tx Data Buffer will be re-transmitted if Synchronous Data mode has been selected the Tx modem is in Start-Stop mode then a continuous Stop signal (1) will be transmitted until a new value is loaded into the Tx Data Register. 2002 Consumer Microcircuits Limited Figure 5a Tx USART 10 CMX868 ...
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... V.22 signals are transmitted as a +90 carrier phase change for a ‘0’ bit, +270 for ‘1’. For V.22 and Bell 212A 1200bps DPSK the transmit data stream is divided into groups of two consecutive bits (dibits) which are encoded as a carrier phase change: (left-hand bit is the first of the pair) 2002 Consumer Microcircuits Limited - -17 Dibit Phase change 00 ...
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... Tx Level Control and Tx Output Buffer to the pins TXA and TXAN. The Tx Output Buffer has symmetrical outputs to provide sufficient line voltage swing at low values reduce harmonic distortion of the signal. 2002 Consumer Microcircuits Limited Phase quadrant change 00 +90 (e.g. quadrant ...
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... Status Register to 1 when the signal level exceeds the measurement threshold. dB The Answer Tone detector measures both amplitude and frequency of the received signal and sets bit 6 or bit 7 of the Status Register when a valid 2225Hz or 2100Hz signal is received. 2002 Consumer Microcircuits Limited 10 0 -10 -20 ...
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... Energy Detector block, compared to a threshold value, and the result controls bit 10 of the Status Register. The output of the Receive Modem Filter and Equaliser is also fed to the FSK or QAM/DPSK demodulator depending on the selected modem type. 2002 Consumer Microcircuits Limited 10 0 -10 -20 ...
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... C-BUS Rx Data Register after every 8 bits. In Start-Stop mode the USART Control logic looks for the start of each character, then feeds only the required number of data bits (not parity) into the Rx Data Buffer. The parity bit (if used) and the presence 2002 Consumer Microcircuits Limited 15 CMX868 ...
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... To accommodate the requirements of V.14, the CMX868 Rx Mode Register can be set for 0, +1% or +2.3% overspeed operation in QAM or DPSK Start-Stop modes. Missing Stop bits beyond those allowed by the selected overspeed option will set the Rx Framing Error flag bit of the Status Register. 2002 Consumer Microcircuits Limited Figure 8a Rx Modem Data Paths 16 ...
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... This command resets the device and clears all bits of the General Control , Transmit Mode and Receive Mode Registers and bits 15 and 13-0 of the Status Register. Whenever power is applied to the CMX868 a General Reset command should be sent to the device, after which the General Control Register should be set as required. 2002 Consumer Microcircuits Limited (no data) C-BUS address $01 17 ...
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... Low Power V.22 bis Modem 2002 Consumer Microcircuits Limited Figure 9 C-BUS Transactions 18 CMX868 D/868/6 ...
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... This bit allows the Tx and Rx fixed compromise equalisers in the modem transmit and receive filter blocks to be disabled. b10 = 1 b10 = 0 General Control Register b9: Relay Drive This bit directly controls the RDRVN output pin 2002 Consumer Microcircuits Limited ...
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... General Control Register b5-0: IRQ Mask bits These bits affect the operation of the IRQ bit of the Status Register as described in section 1.5.10.7 2002 Consumer Microcircuits Limited Device powered up normally Powersave mode (all circuits except Ring Detect, RDRVN and C-BUS interface disabled) stabilise before starting to use the transmitter BIAS Internal circuitry in a reset condition ...
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... Consumer Microcircuits Limited C-BUS address $ level Guard tone Scrambler Tx level Unused, set to 0000 Set to 0000 0000 0000 V.22 bis 2400 bps QAM “ V.22/Bell 212A 1200 bps DPSK “ ...
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... Consumer Microcircuits Limited Tx 550Hz guard tone Tx 1800Hz guard tone No Tx guard tone Scrambler enabled, 64 ones detect circuit enabled (normal use) Scrambler enabled, 64 ones detect circuit disabled Scrambler disabled Synchronous mode Start-stop mode, no parity Start-stop mode, even parity bit added to data bits ...
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... Consumer Microcircuits Limited Tone frequency (Hz) No tone 697 770 852 941 1209 1336 1477 1633 1300 (Calling tone) 2100 (Answer tone) 2225 (Answer tone) Tone pair TA Programmed Tx tone or tone pair, see 1.5.10.8 ...
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... Consumer Microcircuits Limited C-BUS address $ level Eq Descrambl Rx level DTMF/Tones/Call Progress select Set to 0000 0000 0000 V.22 bis 2400 bps QAM “ V.22/Bell 212A 1200 bps DPSK “ V.22 600 bps DPSK “ ...
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... Consumer Microcircuits Limited Enable auto-equaliser DPSK mode: Auto-equaliser disabled QAM mode : Auto-equaliser settings frozen Descrambler enabled, 64 ones detect circuit enabled (normal use) Descrambler enabled, 64 ones detect circuit disabled Descrambler disabled Rx Synchronous mode Rx Start-stop mode, no overspeed Rx Start-stop mode, +1% overspeed ( missing Stop bits allowed) Rx Start-stop mode, +2 ...
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... In unformatted Rx data mode this register contains 8 received data bits the register holding the earliest received bit, b7 the latest Start-Stop data mode this register contains the specified number of data bits from a received character, b0 holding the first received bit. 2002 Consumer Microcircuits Limited C-BUS addresses $E3 and $ ...
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... Set framing error b3 Set even Rx parity b2 QAM/DPSK Rx signal quality b2 b1 QAM/DPSK Rx signal quality b1 b0 QAM/DPSK Rx signal quality b0 or FSK frequency demodulator output 2002 Consumer Microcircuits Limited C-BUS address $ See below for uses of these bits IRQ Set Ring Detect Programming Flag bit ...
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... The ‘continuous 0’ and ‘continuous 1’ detectors monitor the Rx signal after the QAM/DPSK descrambler, (see Figure 8a) and hence will detect continuous the descrambler is disabled, or continuous scrambled the descrambler is enabled. 2002 Consumer Microcircuits Limited Descrambler enabled (DPSK/QAM modes only) ...
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... Received DTMF Code: b3-0 of Status Register 2002 Consumer Microcircuits Limited Low frequency (Hz) High frequency 941 697 697 697 770 770 770 852 852 852 941 941 941 697 770 852 29 Keypad symbol ...
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... Transmit Tone Pair Programming 4 transmit tone pairs (TA to TD) can be programmed. The frequency (max 3.4kHz) and level must be entered for each tone to be used. Single tones are programmed by setting both level and frequency values to zero for one of the pair. 2002 Consumer Microcircuits Limited ...
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... The programmable tone pair detector is implemented as shown in Figure 12a. The filters are 4 sections. The frequency detectors measure the time taken for a programmable number of complete input signal cycles and compare this time against programmable upper and lower limits. 2002 Consumer Microcircuits Limited Value written 32768 ...
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... Rx Gain Control block set to 0dB - are nominally: ‘Off’ to ‘On’ ‘On’ to ‘Off’ 2002 Consumer Microcircuits Limited Figure 12b Filter Implementation -44.5dBm -47.0dBm ...
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... Note that if any changes are made to the programmed values while the CMX868 is running in Programmed Tone Detect mode they will not take effect until the CMX868 is next switched into Programmed Tone Detect mode. On powerup or after a reset, the programmable tone pair detector is set to act as a simple 2130Hz + 2750Hz detector. 2002 Consumer Microcircuits Limited 33 CMX868 D/868/6 ...
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... If the S1 signal had not been detected within 270ms after step 5 then monitor for scrambled 1s at 1200bps. 15. When scrambled 1s (at 1200bps) have been received for 270ms enable the Rx USART, set a 765ms timer and load the Tx Data Register with the first data to be transmitted. 2002 Consumer Microcircuits Limited 34 CMX868 D/868/6 ...
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... If scrambled 1s had been detected for 270ms in step 6, set the Tx Mode Register to V.22 High Band 1200bps scrambled 1s transmission and set a 765ms timer and enable the Rx USART. 16. Load the Tx Data Buffer with the first data to be transmitted. 2002 Consumer Microcircuits Limited 35 CMX868 D/868/6 ...
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... A 1200bps data connection has now been established. 1.6.3 Reference Diagrams The circuit diagrams in the EV8680 and DE8681 kits should be consulted for examples of a complete telephone line interface. These diagrams are contained in their respective User Manuals, which can be downloaded from the CML website. 2002 Consumer Microcircuits Limited 36 CMX868 D/868/6 ...
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... Storage Temperature Operating Temperature P4 Package Total Allowable Power Dissipation at Tamb = 25°C ... Derating Storage Temperature Operating Temperature 1.7.1.2 Operating Limits Correct operation of the device outside these limits is not implied. Supply ( Operating Temperature 2002 Consumer Microcircuits Limited pins SS Notes 37 Min. Max. Units -0.3 7 0.3 V ...
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... X1, C1 and C2. 2. All logic inputs General Mode Register b8 and b7 both set Excluding RD and RT pins. 3.5 3 2.5 2 Vin 1.5 1 0.5 0 2.5 Figure 13 Typical Schmitt Trigger Input Voltage Thresholds vs. V 2002 Consumer Microcircuits Limited 0.01% (100ppm) Notes 3.0V 5.0V ...
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... Transmit Bell 202 FSK Mode Baud rate Mark (logical 1) frequency, 1200 baud Space (logical 0) frequency, 1200 baud Mark (logical 1) frequency, 150 baud Space (logical 0) frequency, 150 baud DTMF/Single Tone Transmit Tone frequency accuracy Distortion 2002 Consumer Microcircuits Limited Notes Min. Typ Notes Min ...
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... Measured on the 2 or 4-wire line using the line interface circuits described in section 1.4.2 with the Tx line signal level set to -10dBm for QAM, DPSK, FSK or single tones, - 6dBm and -8dBm for DTMF tones. Excludes any distortion due to external components such as the line coupling transformer. 2002 Consumer Microcircuits Limited Notes Min ...
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... Mark (logical 1) frequency Space (logical 0) frequency 150 baud Acceptable baud rate Mark (logical 1) frequency Space (logical 0) frequency Rx Modem Signal (FSK, DPSK and QAM Modes) Signal level Signal to Noise Ratio (noise flat 300-3400Hz) 2002 Consumer Microcircuits Limited Notes Min. Typ. 2392 2400 1192 1200 9 - ...
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... FSK modes. Fixed compromise line equaliser enabled. Signal switched between off and -33dBm 12. ‘Typical’ value refers to 2100Hz or 2225Hz signal switched between off and -33dBm. Times measured wrt. received line signal 13. ‘Typical’ values refers to 400Hz signal switched between off and -33dBm 2002 Consumer Microcircuits Limited Notes Min. Typ. 90 ...
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... Not Detect’ DTMF signal duration Pause length detected Pause length ignored Notes: 14. Referenced to DTMF tone of lower amplitude. 15 Flat Gaussian Noise in 300-3400Hz band. Receive Input Amplifier Input impedance (at 100Hz) Open loop gain (at 100Hz) Rx Gain Control Block accuracy 2002 Consumer Microcircuits Limited Notes Min. Typ. 10 -30 -10 ...
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... Maximum 30pF load on each C-BUS interface line. Note: These timings are for the latest version of the C-BUS as embodied in the CMX868, and allow faster transfers than the original C-BUS timings given in CML Publication D/800/Sys/3 July 1994. 2002 Consumer Microcircuits Limited Notes Min. ...
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... Low Power V.22 bis Modem 1.7.2 Packaging Figure 16a 24-pin SOIC (D2) Mechanical Outline: Order as part no. CMX868D2 Figure 16b 24-pin TSSOP (E2) Mechanical Outline: Order as part no. CMX868E2 2002 Consumer Microcircuits Limited 45 CMX868 D/868/6 ...
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Low Power V.22 bis Modem Figure 16c 24-pin DIL (P4) Mechanical Outline: Order as part no. CMX868P4 Handling precautions: This product includes input protection, however, precautions should be taken to prevent device damage from electro-static discharge. CML does not assume ...
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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. ...