CMX639 CML Microcircuits, CMX639 Datasheet
CMX639
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CMX639 Summary of contents
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... With its robust and selectable coding algorithms, low cost, very low power, and small size, the CMX639 is ideal for use in a wide variety of consumer and business digital voice applications. Its completely integrated CODEC simplifies design and eliminates the costs, complexity and risk of external filters and software algorithms ...
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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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... Negative Supply No Connection output The recovered analog signal is output at this pin the buffered output of a lowpass filter and requires external components. During ‘Powersave’ this output is open circuit. No Connection 4 CMX639 Description pull-up. pull-up. /2, this pin should be externally DD CMX639/2 ...
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... Encode and Decode data clock ports may be employed in the External Clocks mode. Internal 1M pull-ups. See Table 3. power Positive Supply. A single 3.0V to 5.5V supply is required. This pin should be externally decoupled capacitor C5 CMX639 Description /2. When this pin is a logical DD pull-up. CMX639/2 ...
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... Oscillator inverter bias resister 2. Xtal circuit load capacitor 3. The drive source impedance connected to the coupling capacitor’s input node, rather than the CMX639 ENCODER INPUT pin node, should be should be less than 1k . Output idle channel noise levels will improve with even lower source impedances driving the coupling capacitor’s input node. ...
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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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... Min. Max. Units 800 mW 10 mW/°C -40 +125 °C -40 +85 °C Min. Max. Units 300 mW 3.0 mW/°C -40 +125 °C -40 +85 °C Min. Max. Units 800 mW 10 mW/°C -40 +125 °C -40 +85 °C Min. Max. Units 2.7 5.5 V -40 +85 °C 0.500 2.048 MHz CMX639 CMX639/2 ...
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... 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. 1.0 1 300 2 100 CMX639 Max. Units 800 A dB CMX639/2 ...
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... Consumer Microcircuits Limited Notes Min. Typ. 7 -37 7 -33 160 4 3240 5 7 -37 7 -33 4 3200 4 300 -3 -63 5 10, 11 0.500 1.024 10 CMX639 Max. Units 3400 Hz 10 kHz dB dB 3.0 dB dBm0p dBm0p 450 s 750 s 1500 s 2.048 MHz CMX639/2 ...
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... Encoder Decoder (Full Codec) passband of 300Hz min. to 3400Hz max. for a 1.024MHz Xtal/Clock will shift to 600Hz min. to 6800Hz max. when the device is operated from a 2.048MHz Xtal/Clock. For this reason, all CMX639 codecs involved in the same communications link should usually be operated from the same Xtal/Clock frequency. ...
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... PCO DATA CLOCKED DATA TRUE TIME MULTIPLEXING FUNCTION HIGH Figure 4 Serial Bus Timing = 3.0V to 5.0V, Tamb = - 40°C to +85°C. DD Notes 12 HIGH Min. Typ. Max. 1.0 1.0 0 100 100 450 600 1.5 750 100 100 CMX639 Units CMX639/2 ...
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... 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 = 1.024MHz Input Level = -20dB 64kb/s 32kb/s 16kb/s 2500 3000 3500 CMX639/2 ...
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... 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 -40 -30 -20 -10 Input Level (dB) CMX639 64 kbps 32 kbps 16 kbps ref. 0 CMX639/2 ...
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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 ...
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... In the process of creating a more global image, the three standard product semiconductor companies of CML Microsystems Plc (Consumer Microcircuits Limited (UK), MX-COM, Inc (USA) and CML Microcircuits (Singapore) Pte Ltd) have undergone name changes and, whilst maintaining their separate new names (CML Microcircuits (UK) Ltd, CML Microcircuits (USA) Inc and CML Microcircuits (Singapore) Pte Ltd), now operate under the single title circuits ...