CMX808AE3 CML Microcircuits, CMX808AE3 Datasheet

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D/808A/5 March 1999 1.0 Features Unique CTCSS ‘Type 2’ Operation Fast Decode on all Tones (140ms) Tones from 60Hz to 251Hz Tone Cloning Low Power Operation (1.3mA at 3.0V) 1.1 Brief Description This device is a unique product for the ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder Section 1.0 Features ......................................................................................................1 1.2 Block Diagram ............................................................................................3 1.3 Signal List ...................................................................................................4 1.4 External Components.................................................................................6 1.5 General Description....................................................................................7 1.5.1 Software Description ..................................................................7 1.6 Application Notes .....................................................................................14 1.6.1 General ......................................................................................14 1.6.2 Transmitter ................................................................................14 ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.2 Block Diagram 1999 Consumer Microcircuits Limited Figure 1 Block Diagram 3 CMX808A D/808A/5 ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.3 Signal List Package E3 P4 Pin No. Pin No XTALN 2 2 XTAL/CLOCK 3 3 SERIAL CLOCK 4 4 COMMAND DATA 5 5 REPLY DATA 6 6 CSN 7 ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.3 Signal List (continued) Package E3 P4 Pin No. Pin No A/D CAP BIAS 12 14 ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.4 External Components C1 22pF C2 22pF C3 0.1µF C4 0.1µF C5 100pF C6 0.1µF C7 Note 1 C8 0.1µF Note: 1. R3, R4, C5 and C7 form the gain components for ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.5 General Description The CMX808A is a programmable CTCSS ‘Type 2’ encoder and decoder for Family Radio, see Figure 1. The receiver of the CMX808A decodes a user-programmable set ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder Write Only Register Description GENERAL RESET (Hex address $01) The reset command has no data attached to it. It sets the device registers to zero (all powersaved) with the exception of Bits ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder RX BPF ENABLE When this bit is “1” the audio band-pass filter is enabled and the output of the (Bit 6) filter is switched to RX AUDIO OUT. The output is then ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder CTCSS TX FREQUENCY Register (Hex address $83) This is a 16-bit register. Byte (1) is sent first. When the CTCSS transmitter is enabled, the bits control the frequency of ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder TONE CLONING Register (Hex address $9C) This register enables and disables tone cloning as shown below: $9C = $01 enables tone cloning. $9C = $00 disables tone cloning. Figure 4 shows the ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder The flow chart shows the decoder and transmitter modes of operation for the example below: 1. Decoder, e.g. Address 0 = 100Hz, bandwidth = ±2.7%, interrupt enabled. 2. Transmitter, e. ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder The flow chart shows the tone cloning routine. The first programmed tone set ($0-$6) will decode after typically 140ms, subsequent tone sets will decode almost instantly (i.e. the information is available at ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.6 Application Notes 1.6.1 General The CMX808A is intended for use in radio systems where sub-audio signalling is required for functions such as Family Radio Service (FRS) Handportables, Amateur Radio Equipment, General ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.6.4 Tx Tone Table The following table lists the commonly used CTCSS tones and the corresponding values for programming the CTCSS TX FREQUENCY register $83. Freq. Byte 1 (Hz) (Hex) 67.0 0E ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.6.5 Rx Tone Table The following table lists the commonly used CTCSS tones together with the values for programming the CTCSS RX PROGRAM register $84. N.B. The values for byte 1 and ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.7 Performance Specification 1.7.1 Electrical Performance 1.7.1.1 Absolute Maximum Ratings Exceeding these maximum ratings can result in damage to the device. Supply ( Voltage on any pin ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.7.1.3 Operating Characteristics For the following conditions unless otherwise specified: Xtal Frequency = 4.0MHz Audio Level 0dB ref. = 308mVrms at 1kHz V = 3.0V to 5.0V, Tamb = -40°C to +85°C. ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder Output Impedances TX SUB-AUDIO OUT (Enabled) TX/RX AUDIO OUT (Enabled) TX/RX AUDIO OUT (Disabled) VOLUME OUT (Enabled) Rx Amplifier Open Loop Gain (I/P = 1mV at 100Hz) Unity Gain Bandwidth Input Impedance ...

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Family Radio CTCSS 'Type 2' Encoder and Decoder 1.7.1 Electrical Performance (continued) Timing Diagrams For the following conditions unless otherwise specified: Xtal Frequency = 4.0MHz Parameter t "CS-Enable to Clock-High" CSE t Last "Clock-High to CS-High" CSH t ...

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... Family Radio CTCSS 'Type 2' Encoder and Decoder 1.7.2 Packaging Figure 7 Mechanical Outline: Order as part no. CMX808AE3 Figure 8 Mechanical Outline: Order as part no. CMX808AP4 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 ...

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