CMX654D4 Consumer Microcircuits Limited, CMX654D4 Datasheet
CMX654D4
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CMX654D4 Summary of contents
Page 1
... A 3.58MHz standard Xtal/Clock rate is required and the device operates from a 3.0 to 5.5V supply. Both SOIC (D4) and Plastic DIL (P3) 16-pin package types are available. 1998 Consumer Microcircuits Limited CMX654 V23 Transmit Modulator ...
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... Block Diagram ................................................................................................ 3 1.3 Signal List ....................................................................................................... 3 1.4 External Components .................................................................................... 5 1.5 General Description ....................................................................................... 5 1.5.1 Xtal Osc and Clock Dividers............................................................. 5 1.5.2 Mode Control Logic .......................................................................... 6 1.5.3 FSK Modulator and Transmit Filter .................................................. 6 1.5.4 Tx Data Retiming.............................................................................. 7 1.6 Application Notes........................................................................................... 8 1.6.1 Line Interface.................................................................................... 8 1.7 Performance Specification ............................................................................ 9 1.7.1 Electrical Performance ..................................................................... 9 1.7.2 Packaging....................................................................................... 12 1998 Consumer Microcircuits Limited CONTENTS 2 CMX654 Page D/654/3 ...
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... TXOP 1998 Consumer Microcircuits Limited Figure 1 Block Diagram Description Type O/P The output of the on-chip Xtal oscillator inverter. I/P The input to the on-chip Xtal oscillator inverter. I/P A logic level input for setting the mode of the device. See Section 1.5.2. I/P A logic level input for setting the mode of the device ...
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... V decoupling are very important recommended that the decoupling capacitors are placed so DD BIAS that connections between them and the device pins are as short as practicable. 1998 Consumer Microcircuits Limited Description Type O/P Internally generated bias voltage, held when the device is not in 'Zero-Power' mode. ...
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... 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 significant rise in the supply current drawn by CMX654 as well as generating undefined states of the RDYN output. 1998 Consumer Microcircuits Limited 100k 3.579545MHz ...
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... When modulated at the appropriate baud rates, the Transmit Filter and associated external components (see Section 1.6.1) limit the FSK out of band energy sent to the line in accordance with Figure 3 assuming that the signal on the line is at -6dBm or less. 1998 Consumer Microcircuits Limited Tx Mode 1200bits/sec ...
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... CLK line is pulled high. If the data retiming facility is not required, the CLK input to the CMX654 should be kept high at all times. The asynchronous data to the FSK modulator will then be connected directly to the TXD input pin. This is illustrated in Figure 5. 1998 Consumer Microcircuits Limited 7 CMX654 D/654/3 ...
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... The component(s) 'Z' between points B and C should match the line impedance. Device A1 must be able to drive 'Z' and the line. R3: The levels in dB (relative to a 775mV rms signal) at 'A', 'B' and 'C' in the line interface circuit are 3.3V -3.6dB 5.0V 1998 Consumer Microcircuits Limited C5 C7 Figure 4 Line Interface Circuit 'A' = 20Log(V /5) DD 'B' = 'A' + 20Log(100k /R3) ...
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... Operating Temperature Operating Limits Correct operation of the device outside these limits is not implied. Supply ( Operating Temperature Xtal Frequency Notes Xtal frequency of 3.579545MHz ±0.1% is required for correct FSK operation. 1998 Consumer Microcircuits Limited pins SS Notes 1 9 Min. Max. Units -0.3 7 ...
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... not including any current drawn from the CMX654 pins by external circuitry other than X1, C1 and C2. 2. TXD and CLK inputs Relative to 775mVrms Timing for an external input to the XTAL/CLOCK pin. Data and Mode Timing 1998 Consumer Microcircuits Limited = 3.3V to 5.5V at Tamb = -40 to +85°C, DD 0.1% Notes Min. ...
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... RDY low to CLK going low Data Set-up time Data Hold time h Note: M0 and M1 are preset and stable. FLO and FHI are the two FSK signalling frequencies. 1998 Consumer Microcircuits Limited Figure 5 TXD to TXOP Delay Time Figure 6 FSK Operation with Tx Data Retiming 20.0 - 0.1 ...
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... V.23 Transmit Modulator 1.7.2 Packaging Figure 7 16-pin SOIC (D4) Mechanical Outline: Order as part no. CMX654D4 Figure 8 16-pin DIL (P3) Mechanical Outline: Order as part no. CMX654P3 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 responsibility for the use of any circuitry described. No IPR or circuit patent licences are implied ...
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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. ...