CMX639D4 Consumer Microcircuits Limited, CMX639D4 Datasheet
CMX639D4
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CMX639D4 Summary of contents
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... Multiplexer applications are also well supported by the encoder output’s three-state/high impedance enable feature. The CMX639 operates from 2.7V to 5.5V supplies and is available in the following packages: 24-pin TSSOP (CMX639E2), 16-pin SOIC (CMX639D4) and 22-pin PDIP (CMX639P6). 2000 Consumer Microcircuits Limited CMX639 ...
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... CVSD Codec Section 1.0 Features and Applications ..................................................................1 1.1 Brief Description ..................................................................................1 1.2 Block Diagram......................................................................................3 1.3 Signal List ............................................................................................4 1.4 External Components ..........................................................................6 1.5 General Description.............................................................................7 1.6 Application Notes ................................................................................7 1.7 Performance Specification ..................................................................8 1.7.1 Electrical Performance...............................................................8 1.7.2 Packaging ...............................................................................15 2000 Consumer Microcircuits Limited CONTENTS 2 CMX639 Page CMX639/2 ...
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... CVSD Codec 1.2 Block Diagram 2000 Consumer Microcircuits Limited Figure 1 Block Diagram 3 CMX639 CMX639/2 ...
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... N Decoder Output 14 15 N/C 2000 Consumer Microcircuits Limited Type input Input to the clock oscillator inverter. A 1.024MHz Xtal input or externally derived clock is injected here. No Connection output The 1.024 MHz output of the clock oscillator inverter. No Connection input/ A logic I/O port. External encode clock input or output internal data clock output ...
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... Clock Mode Clock Mode 2000 Consumer Microcircuits Limited Type Input A logic '0' at this pin puts most parts of the codec into a quiescent, non-operational state. When at a logical '1', the codec operates normally. Internal 1 M pull-up. No Connection input A logic '0' at this pin gates a ‘0101...’ pattern ...
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... For best results, a crystal oscillator design should drive the clock inverter input with signal levels of at least 40 peak to peak. Tuning fork crystals generally cannot meet this requirement. To obtain crystal DD oscillator design assistance, please consult your crystal manufacturer. 2000 Consumer Microcircuits Limited 1M 10% C4 33pF ...
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... General Description Data Enable Clock Mode 1 Clock Mode 1.6 Application Notes Figure 3 System Configuration using the CMX639 2000 Consumer Microcircuits Limited Encoder Output Powersave 1 1 Enable 0 don't care High Z (open circuit Table 2 Encoder Output Data/Sampling Clock Rate (CLOCK/XTAL = ...
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... Operating Temperature D4 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 Xtal Frequency 2000 Consumer Microcircuits Limited pins SS Notes 8 Min. Max. Units -0.3 7 0.3 V ...
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... Output Logic ‘1’ Output Logic ‘0’ Digital Input Impedance Logic I/O pins Logic Input pins, Pull-up Resistor Digital Output Impedance Analog Input Impedance Analog Output Impedance Three State Output Leakage Insertion Loss 2000 Consumer Microcircuits Limited Notes Min. Typ. 6 600 6 1.90 6 2.75 ...
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... Forced idle encode/decode control not available on D4 (16-pin SOIC) package. 10. Some applications may benefit from the use of an Xtal/Clock frequency other than 1.024MHz. Note: Codec time constants and filter response curves are effectively proportional to Xtal/Clock frequency 2000 Consumer Microcircuits Limited Notes Min. ...
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... Figure 4. Nonetheless, some Xtal/Clock frequency and data rate combinations are better served by the use of internal clocks. Experimentation with each specific design may provide the best guidance for making this design choice. 2000 Consumer Microcircuits Limited 11 CMX639 ...
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... Data set-up time SU t Data hold time Data true time Clock to output delay time PCO t Data rise time DR t Data fall time DF 2000 Consumer Microcircuits Limited ENCODER TIMING DECODER TIMING PCO DATA CLOCKED ...
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... Figure 5 Typical Frequency Response (32kbps 500 Figure 6 Typical S/N Ratio with Input Frequency 2000 Consumer Microcircuits Limited 1000 1500 2000 Frequency (Hz) 13 CMX639 Input Level = -15dBmO Data Clocks = 32kbps Xtal = 1 ...
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... Input Frequency = 820Hz Input Level (dBmO) Figure 7 Typical Variation of Gain with Input Level (32kbps) 2000 Consumer Microcircuits Limited - Figure 8 Typical S/N Ratio with Input Level 14 Ref: 0dB Input Level = 489mVrms 35 Input Frequency = 820 ...
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... CVSD Codec 1.7.2 Packaging Figure 9 P6 Mechanical Outline: Order as part no. CMX639P6 Figure 10 E2 Mechanical Outline: Order as part no. CMX639E2 2000 Consumer Microcircuits Limited 15 CMX639 CMX639/2 ...
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... CVSD Codec Figure 9 D4 Mechanical Outline: Order as part no. CMX639D4 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 ...