CMX644AD2 Consumer Microcircuits Limited, CMX644AD2 Datasheet
CMX644AD2
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CMX644AD2 Summary of contents
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... The CMX644A can operate on a supply voltage between 3.0V and 5.5V across the full temperature range of -40°C to +85°C. A low impedance pull down output is provided for a hook relay. The CMX644A is pin compatible with the CMX624 V23/Bell 202 modem also from CML. 2000 Consumer Microcircuits Limited CMX644A V.22 and Bell 212A ...
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... Software Description.............................................................10 1.6 Application Notes ..............................................................................21 1.6.1 Line Interface.........................................................................21 1.6.2 Ring Detector Interface .........................................................23 1.6.3 Software Protocol for Transmitting PSK Data Bytes...........24 1.6.4 Software Protocol for Receiving PSK Data Bytes ...............25 1.6.5 Handling Underflow and Overflow Conditions....................25 1.7 Performance Specification ................................................................27 1.7.1 Electrical Performance..........................................................27 1.7.2 Packaging ..............................................................................32 2000 Consumer Microcircuits Limited CONTENTS 2 CMX644A Page D/644A/6 ...
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... V22 and Bell 212A Modem 1.2 Block Diagram 2000 Consumer Microcircuits Limited Figure 1 Block Diagram 3 CMX644A D/644A/6 ...
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... IRQN 8 TOP 9 TXO 10 TXN 11 TXON 2000 Consumer Microcircuits Limited Signal Type O/P The inverted output of the on-chip oscillator. I/P The input to the on-chip oscillator, for external Xtal circuit or clock. I/P The ‘C-BUS’ serial clock input. This clock, produced by the Controller, is used for the transfer timing of commands to and from the device ...
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... CMX644A area to provide a low impedance connection between the V SS pin and the V DD and V BIAS decoupling capacitors. The receive path should be protected as much as possible from extraneous signals. 2000 Consumer Microcircuits Limited Signal Type P The negative supply rail (ground) ...
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... The on-chip oscillator is turned off in the 'Zero-Power' mode. If the clock is provided by an external source which is not always running, then the 'Zero-Power' mode must be set when the clock is not available. Failure to observe this rule may cause a rise in the supply current drawn by CMX644A. 2000 Consumer Microcircuits Limited * 6 CMX644A ...
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... SCI, SPI and Microwire, and may also be easily implemented with general purpose µC I/O pins controlled by a simple software routine. See section 1.7.1 and Figure 9 for detailed ‘C-BUS’ timing requirements. 2000 Consumer Microcircuits Limited Figure 3 ‘C-BUS’ Transactions 7 ...
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... Failure to load the TX DATA BYTE Register with a new value when required will result in bit 2 (TX DATA UNDERFLOW) of the FLAGS Register being set to ‘1’ and a continuous Mark (‘1’) signal will then be transmitted until a new value is loaded into TX DATA BYTE Register. 2000 Consumer Microcircuits Limited Figure 4a Transmit UART Function (Async) 8 ...
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... FLAGS Register will also be set to ‘1’. The C-BUS serial clock should be fast enough to ensure that an RX DATA READY interrupt is serviced completely within a time which is less than 8 bit-times at 1200 baud, i.e. in less than 6.67ms. 2000 Consumer Microcircuits Limited Figure 4b Receive UART Function (Async) 9 ...
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... GENERAL RESET ($01) The reset command has no data attached to it. Application of the GENERAL RESET sets all write-only register bits to ‘0’. SET-UP Register ($E0) (Bit 7) RELAY DRIVE (Bit 6) DETECT DET1 and DET0 (Bits 5 and 4) 2000 Consumer Microcircuits Limited BIT 6 BIT 5 BIT 4 (D6) (D5) (D4) N/A N/A ...
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... V22 and Bell 212A Modem LOOPBACK L1 and L0 (Bits 3 and 2) XTAL FRQ X1 and X0 (Bits 1 and 0) 2000 Consumer Microcircuits Limited These 2 bits control internal signal paths such that loopback tests can be performed. Function is according to the following table Bit 3 Bit Normal Device Operation: no loopback. ...
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... Consumer Microcircuits Limited This bit selects the “Answer Tone” frequency in the receive detector. A ‘0’ selects 2225Hz and a ‘1’ selects 2100Hz. This bit should be used to begin and end the transmission of tones once the required frequency has been programmed. When set to ‘1’ the tone will be transmitted ...
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... Bits (TG0 to TG3) control the levels of the transmit path gain block according to the following table: TG3 (Bit 2000 Consumer Microcircuits Limited RG2 RG1 RG0 (Bit 2) (Bit 1) (Bit ...
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... PARITY ENABLE (Bit 2) PARITY ODD/EVEN (Bit 1) DATA BITS 8/7 (Bit 0) 2000 Consumer Microcircuits Limited Note that the left-hand digit of the dibit is the one occurring first in the data stream + enters the modulator portion of the 0 modem after the scrambler. Reserved for future use. These bits should be set to ‘0’. ...
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... ENABLE (Bit 1) HI/LO BAND (Bit 0) 2000 Consumer Microcircuits Limited Reserved for future use. This bit should be set to ‘0’. This bit enables or powersaves the inverted output of the line driving amplifier (TXON). When set to ‘1’ TXON is enabled; together with TXO these outputs provide sufficient complementary output to drive a line even at low VDD. When set to ‘ ...
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... ENABLE (Bit 1) HI/LO BAND (Bit 0) 2000 Consumer Microcircuits Limited Reserved for future use. This bit should be set to ‘0’. When this bit is set to ‘1’ the Call Progress Detector bandwidth is approximately 300Hz - 620Hz. When this bit is set to ‘0’ the Call Progress Detector bandwidth is approximately 400Hz - 620Hz. When this bit is set to ‘ ...
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... UNSCRAM MARK mask (Bit 0) 2000 Consumer Microcircuits Limited When this bit is set to ‘1’ it enables an interrupt that occurs when the RX PARITY flag (Bit 7, FLAGS Register, $EF) changes from ‘0’ to ‘1’ i.e. there PARITY error. When this bit is ‘0’ the interrupt is masked. When this bit is set to ‘ ...
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... The flags register is used to indicate when the device requires attention. When a flag becomes set to ‘1’ and its corresponding mask bit is ‘1’ then an interrupt (IRQN) will be generated. Immediately after the flags register has been read, all the bits will be reset to ‘0’ and consequently any interrupt will be cleared. 2000 Consumer Microcircuits Limited BIT 6 BIT 5 ...
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... TX DATA READY flag (Bit 1) UNSCRAM MARK flag (Bit 0) 2000 Consumer Microcircuits Limited When this bit is ‘1’ the received parity is in error. When this bit is ‘0’ the received parity is correct. When RING DETECT (TONES DETECT Register, Bit 6) changes state, this bit will be set to ‘1’. ...
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... The CMX644A utilises two internal equalisers - one is configured for the High Band, the other for the Low Band. The Transmit and Receive paths will be internally switched through the equaliser appropriate to their HI/LO BAND settings. In the event of both Transmit and Receive paths being set to the same band, both equalisers will be bypassed. 2000 Consumer Microcircuits Limited Lowband 800 900 ...
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... Note Relay circuit, ac and dc loads and line protection are not shown for clarity. R10 600 R11 See text R12 100k R13 See text 2000 Consumer Microcircuits Limited 4-wire line. The line terminations are provided by R10 (5.0 (Input transformer loss * 2.0) R14 100k R15 600 Resistors 1%, capacitors 20%. Figure 6a 4-Wire Line Interface Circuit ...
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... R11 and R13 should be calculated in the same way as for the 4-wire interface circuit of Figure 6a. Note that the component values R17 and C13 depend on the transformer characteristics and should be adjusted to achieve a flat frequency response measured at the RXO pin. 2000 Consumer Microcircuits Limited LOG10(2 R14/R13 ...
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... With R20 - 22 all 470k as Figure 7, then setting R23 to 68k 40Vrms and above for V DD over the range 3.0 to 5.5V. R20,21,22 R23 R24 Figure 7 Ring Signal Detector Interface Circuit 2000 Consumer Microcircuits Limited [R20 + R22 + R23] / R23 ) will guarantee detection of ringing signals of C20,21 470k See text C22 ...
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... Wait for a TX DATA READY generated interrupt (read FLAGS to check and clear the IRQ). 8. Load next TX DATA BYTE Note that the transmission should be terminated by setting the ENABLE bit (TX PSK MODE Register) to ‘0’. 2000 Consumer Microcircuits Limited exp(-t/(R24 x C22)) ] and 0.33 F) give a minimum RT charge time of 24 CMX644A ...
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... To change the number of Tx stop bits transmitted with all subsequent data (STOP BITS A and B), first wait until the TX DATA READY flag is set. If this check is not made, then the number of stop bits in the Tx data byte which is currently being sent will be changed. 2000 Consumer Microcircuits Limited and T ) when changing register settings. eg ...
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... V22 and Bell 212A Modem 2000 Consumer Microcircuits Limited Figure 8 ASYNC MODE (Rx and Tx) 26 CMX644A D/644A/6 ...
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... 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. Nominal Xtal frequencies are 3.6864MHz, 7.372800MHz, 11.0592MHz. Supply ( Operating Temperature Xtal Frequency 2000 Consumer Microcircuits Limited Min. -0.3 -0 0.3 -50 0 -20 Min. - ...
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... Guard Tones Level (below PSK) of 550Hz Level (below PSK) of 1800Hz Frequency Accuracy PSK Output Transmitted level Distortion DTMF Output Transmitted level: high group Twist (high group - low group levels) Distortion Frequency Accuracy 2000 Consumer Microcircuits Limited Notes Min 70 ...
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... Gain Block when a signal is detected and by removing this step when the signal is no longer detected. 8. Measured with a 511-bit pseudorandom sequence. 9. Depending on the setting of the CPBW SELECT bit in the RX PSK MODE Register. 10. Measured without equalisation. 2000 Consumer Microcircuits Limited Notes Min. Typ. - ...
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... Tx Delay from Tx data loaded (TDEL) Tx Output to Tx reload signal (TLOAD) Tx Parity to Tx Underflow flag set (TUFL) Rx Timings (See Figure 4b) Parity to Rx Data Ready flag set (TRDY) 2000 Consumer Microcircuits Limited Figure 9 Typical Schmitt Trigger Input Voltage vs Notes 10 10 ...
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... Reply Data Hold time Note: These timings are for the latest version of the ‘C-BUS’ as embodied in the CMX644A, and allow faster transfers than the original ‘C-BUS’ timings given in CML Publication D/800/Sys/3 July 1994. 2000 Consumer Microcircuits Limited Notes Min. 100 ...
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... V22 and Bell 212A Modem 1.7.2 Packaging Figure 11a 24-pin SOIC (D2) Mechanical Outline: Order as part no. CMX644AD2 Figure 11b 24-pin SSOP (D5) Mechanical Outline: Order as part no. CMX644AD5 2000 Consumer Microcircuits Limited 32 CMX644A D/644A/6 ...
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V22 and Bell 212A Modem Figure 11c 24-pin DIL (P4) Mechanical Outline: Order as part no. CMX644AP4 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. ...