CMX865 CML Microcircuits, CMX865 Datasheet
CMX865
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CMX865 Summary of contents
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... The CMX865 operates from a single 3.0 to 3.6V supply over a temperature range of -40°C to +85°C and is available in a 24-pin SOIC package. ...
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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 D/865/3 ...
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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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... Interrupt Request input. This output is pulled down when inactive. An external pullup resistor is required i. Figure 2. 4 Description if Ring Detector not used. SS generated bias voltage /2, except when the device is DD will discharge BIAS SS when active and is high impedance CMX865 D/865/3 ...
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... Tuning-fork Xtals generally cannot meet this requirement. To obtain Xtal DD oscillator design assistance, please consult your Xtal manufacturer. © 2005 CML Microsystems Plc 68kΩ 11.0592MHz or 12.288MHz ground plane in the CMX865 area to provide a low SS pins and the C1, C2 ...
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... The signal at point X is further attenuated by the potential divider formed by R22 and R23 before being applied to the CMX865 RD input. If the amplitude of the signal appearing greater than the input threshold (Vthi) of Schmitt trigger 'A' then the N transistor connected to RT will be turned on, pulling the voltage discharging the external capacitor C22 ...
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... CML Microsystems Plc towards exp(-t/(R24 x C22 C10 C11 Resistors ±5%, capacitors ±20% Figure 4a 2-Wire Line Interface Circuit 7 can be derived from the formula and See Figure 2 33nF 100pF CMX865 , then DD . D/865/3 ...
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... Rx Gain Control gain setting in the Rx Mode Register. The signal level into the CMX865 is affected by the line coupling transformer loss and the values of R11 and R12 of Figure 4a. Assuming 1dB transformer loss, the Rx Gain Control programmed to 0dB and R12 = 100kΩ, then for correct operation (see section 7 ...
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... Transmit and receive line level settings and the value of R11 are as for the 2-wire circuit. R10, 13 See text R11 See text R12 100kΩ © 2005 CML Microsystems Plc C3 C11 C12 Resistors ±5%, capacitors ±20% Figure 4b 4-Wire Line Interface Circuit 9 CMX865 See Figure 2 100pF 33nF D/865/3 ...
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... Call progress signal detect. User programmed tone or tone pair detect. Disabled. The CMX865 may also be set into a powersave mode which disables all circuitry except for the C-BUS interface and the Ring Detector. © 2005 CML Microsystems Plc 10 ...
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... Start-Stop mode then a continuous Stop signal (1) will be transmitted until a new value is loaded into the Tx Data Register. 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. © 2005 CML Microsystems Plc Figure 5a Tx USART 11 CMX865 D/865/3 ...
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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 of V reduce harmonic distortion of the signal. © 2005 CML Microsystems Plc 12 CMX865 and to DD D/865/3 ...
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... The Answer Tone detector measures both amplitude and frequency of the received signal and sets the Status Register when a valid 2225Hz or 2100Hz signal is received. © 2005 CML Microsystems Plc 10 0 -10 -20 -30 -40 -50 -60 0 0.5 1 1.5 2 kHz Figure 6a Response of Call Progress Filter 13 2.5 3 3.5 4 CMX865 D/865/3 ...
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... 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 compromise line equalisation for 1200bps modem modes. The characteristics of the bandpass filter and equaliser are determined by the chosen receive modem type and frequency band ...
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... Framing Error bit will also be set to ‘1’ and the USART will re-synchronise onto the next ‘1’ – ‘0’ (Stop – Start) transition. The Rx Framing Error bit will remain set until the next character has been received. Figure 7b Rx USART Function (Start-Stop mode, 8 Data Bits + Parity) © 2005 CML Microsystems Plc Figure 7a Rx Modem Data Paths 15 CMX865 D/865/3 ...
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... Address byte sent from the µC which may be followed by a one or more data byte(s) sent from the µ written into one of the CMX865’s Write Only Registers one or more byte(s) of data read out from one of the CMX865’s Read Only Registers, as illustrated in Figure 8. ...
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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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... 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 allows the fixed compromise equalisers in the Tx and Rx signal paths to be disabled if desired, and sets the internal clock dividers to use either a 11.0592 ...
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... Reset bit should also be set to 1 and should be held at 1 for 20ms while the internal circuits, Xtal oscillator and V General Control Register b7: Reset Setting this bit to 1 resets the CMX865’s internal circuitry, clearing all bits of the Transmit and Receive Mode Registers and b13-0 of the Status Register ...
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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 b7 (Reset) of the General Control Register ...
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... Data bytes from Tx Data Buffer Continuous 1s Continuous 0s Continuous alternating 1s and 0s 21 CMX865 D/865/3 ...
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... High frequency (Hz) 941 697 697 697 770 770 770 852 852 852 941 941 941 697 770 852 22 “ “ “ Keypad symbol 1633 D 1209 1 1336 2 1477 3 1209 4 1336 5 1477 6 1209 7 1336 8 1477 9 1336 0 1209 * 1477 # 1633 A 1633 B 1633 C CMX865 D/865/3 ...
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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 b7 (Reset) of the General Control Register is 1. ...
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... Reserved Rx USART function disabled 8 data bits + parity 8 data bits 7 data bits + parity 7 data bits 6 data bits + parity 6 data bits 5 data bits + parity 5 data bits Programmable Tone Pair Detect Call Progress Detect 2100Hz, 2225Hz Answer Tone Detect DTMF Detect Disabled 24 CMX865 D/865/3 ...
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... In Rx synchronous mode, this register contains 8 received data bits the register holding the earliest received bit, b7 the latest Start-Stop mode, this register contains the specified number of data bits from a received character, b0 holding the first received bit. © 2005 CML Microsystems Plc C-BUS address $ C-BUS address $ CMX865 D/865/3 ...
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... IRQ Mask bit is 1. The IRQ bit is cleared by a read of the Status Register or a General Reset command or by setting the General Control Register to 1. The operation of the data demodulator and pattern detector circuits within the CMX865 does not depend on the state of the Rx energy detect function. ...
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... In Rx modem modes b2-1 will be zero and b0 will show the output of the frequency demodulator, updated at 8 times the nominal data rate. Figure 9b Operation of Status Register in DTMF Rx Mode © 2005 CML Microsystems Plc ) when the IRQ bit of the Status Register and the SS 27 CMX865 D/865/3 ...
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... Received DTMF Code: Status Register b3-0 28 Keypad symbol (Hz) 1633 D 1209 1 1336 2 1477 3 1209 4 1336 5 1477 6 1209 7 1336 8 1477 9 1336 0 1209 * 1477 # 1633 A 1633 B 1633 C CMX865 D/865/3 ...
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... Value to be entered = desired Vrms * 93780 / V i.e. for 0.5Vrms at VDD = 3.3V, the value to be entered is 14209 (3781 in Hex) Note that allowance should be made for the transmit signal filtering in the CMX865 which attenuates the output signal for frequencies above 2kHz by 0.25dB at 2.5kHz, by 1dB at 3kHz and by 2.2dB at 3.4kHz. ...
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... Filter #2 coefficient Filter #2 coefficient Filter #2 coefficient Filter #2 coefficient Filter #2 coefficient Filter #2 coefficient Filter #2 coefficient Filter #2 coefficient Filter #2 coefficient Filter #2 coefficient Freq measurement #2 ncycles 26 Freq measurement #2 mintime 27 Freq measurement #2 maxtime CMX865 th order IIR D/865/3 ...
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... The design of the IIR filters should make allowance for the fixed receive signal filtering in the CMX865 which has a low pass characteristic above 1.5kHz of 0.4dB at 2kHz, 1.2dB at 2.5kHz, 2.6dB at 3kHz and 4.1dB at 3.4kHz. ‘ ...
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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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... Correct operation of the device outside these limits is not implied. Supply ( Operating Temperature © 2005 CML Microsystems Plc pins SS Notes 33 Min. Max. Units -0.3 4 -50 +50 mA +50 mA -20 +20 mA Min. Max. Units 1000 mW 13 mW/°C -55 +125 °C -40 +85 °C Min. Max. Units 3.0 3.6 V -40 +85 °C CMX865 D/865/3 ...
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... Figure 11) RDRVN ‘ON’ resistance to V RDRVN ‘OFF’ resistance to V Notes 25°C, not including any current drawn from the CMX865 pins by external circuitry other than X1, C1 and C2. 2. All logic inputs General Mode Register b8-7 set to 11. ...
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... Notes Min 1200/75 1298 2097 389 449 Notes Min 1200/150 1198 2197 386 486 Notes Min. -0 3.3V (levels are proportional CMX865 Typ. Max. Units 300 - Baud 2225 2228 Hz 2025 2028 Hz 1270 1272 Hz 1070 1072 Hz Typ. Max. Units - Baud 1300 1302 ...
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... Tx line signal level set to –9.2dBm for FSK or single tones, -5.2dBm and – 7.2dBm for DTMF tones. Excludes any distortion due to external components such as the line coupling transformer. © 2005 CML Microsystems Plc Notes Min. 6 -3.2 6 -1.2 6 -1.0 6 -0.25 Bell 202 100 1000 Hz 36 Typ. Max. -2.2 -1.2 -0.2 + 0.8 - +1.0 - +0.25 10000 100000 CMX865 Units dBm dBm dB dB D/865/3 ...
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... Notes Min. Typ. 1188 1200 1180 1200 2180 2200 148 150 377 387 477 487 Notes Min. Typ CMX865 Max. Units 303 Baud 2237 Hz 2037 Hz 1282 Hz 1082 Hz Max. Units 1212 Baud 1320 Hz 2120 Hz 76 Baud 398 Hz 458 Hz Max ...
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... Notes Min. Typ -48 2 30.0 33 7.0 18.0 2050 - - - 2160 - 2335 - Notes Min. Typ. 275 - -42 30.0 36 6.0 8.0 38 CMX865 Max. Units -43.0 dBm - dBm - dB 30.0 ms 60.0 ms 40.0 ms 80.0 ms Max. Units -43.0 dBm - dBm - dB 45.0 ms 25.0 ms 2160 Hz 2000 Hz 2285 Max. Units 665 Hz -37.0 dBm - dBm 45 ...
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... Rx Gain Control Block accuracy © 2005 CML Microsystems Plc Notes Min. Typ. 8 -31 -10.0 - ±2 12 14 25.0 30 – 13 Notes Min. Typ. 10.0 10000 -0.25 39 CMX865 Max. Unit 2.0 dBm -38.0 dBm 10 ±3.5 % 0.0 dB 10.0 dB 20.0 dB -10.0 dB 40 15.0 ms – falses/ 30mins Max. Units Moh m V/V +0.25 dB D/865/3 ...
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... Command Data Hold time CDH t Reply Data Set-Up time RDS t Reply Data Hold time RDH 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 CMX865. © 2005 CML Microsystems Plc Notes Min. 100 100 0.0 - 1.0 ...
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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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... Industrial Building, Singapore 349307 Tel: +65 6745 0426 800 638 5577 Fax: +65 6745 2917 Sales: sg.sales@cmlmicro.com Technical Support: sg.techsupport@cmlmicro.com CMX865 No. 218, Tian Mu Road West, Tower 1, Unit 1008, Shanghai Kerry Everbright City, Zhabei, Shanghai 200070, China. Tel: +86 21 6317 4107 +86 21 6317 8916 ...