CMX624P4 CMLMICRO [CML Microcircuits], CMX624P4 Datasheet
CMX624P4
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CMX624P4 Summary of contents
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CML Microcircuits COMMUNICA TION SEMICONDUCTORS D/624/7 September 2003 Features V.23 / Bell 202 Compatible Modem Integrated DTMF Encoder Call Progress Tone Detection Line Reversal and Ring Detector Low Power Operation (2.7V) Part of the CMX6x4 Modem Series 1.1 Brief Description ...
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V23 / Bell 202 Modem Section 1.1 Brief Description ..................................................................................... 1 1.2 Block Diagram ......................................................................................... 3 1.3 Signal List ................................................................................................ 4 1.4 External Components ............................................................................. 6 1.5 General Description ................................................................................ 6 1.5.1 Xtal Osc and Clock Dividers ..................................................... 6 1.5.2 ...
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V23 / Bell 202 Modem 1.2 Block Diagram 2003 CML Microsystems Plc Figure 1 Block Diagram 3 CMX624 D/624/7 ...
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V23 / Bell 202 Modem 1.3 Signal List CMX624 Signal D2/D5/P4 Pin No. Name XTALN 1 XTAL/CLOCK 2 SERIAL 3 CLOCK COMMAND 4 DATA REPLY DATA 5 CSN 6 IRQN 7 TOP 8 TXO 9 TXN 10 TXON 11 V ...
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V23 / Bell 202 Modem CMX624 Signal D2/D5/P4 Pin No. Name RXN 16 RXO Notes: I/P = Input O/P = Output BI = Bidirectional ...
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V23 / Bell 202 Modem 1.4 External Components R1 X1 Resistors 5%, capacitors 10% unless otherwise stated. * This component is only required for compatibility with CMX644A, see CMX644A Data Sheet for further details. Figure 2 Recommended External Components for ...
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V23 / Bell 202 Modem 1.5.2 Rx Input Amplifier This amplifier, with suitable external components, is used to adjust the received signal to the correct amplitude for the FSK receiver and Energy Detect circuits and may also form part of ...
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V23 / Bell 202 Modem 1.5.4 FSK Demodulator This block is enabled when bits 1 and 5 of the FSK MODE Register are set to ‘1’, and converts the 75, 150 or 1200 bps FSK input signal to a binary ...
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V23 / Bell 202 Modem Bell 202 mode (bit 7 of SETUP register = ‘1’): FSK MODE Reg FSK / DTMF Modulator block output Bit 1 Bit When bit 7 of the TX ...
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V23 / Bell 202 Modem 0 -10 -20 -30 dBm -40 -50 -60 -70 10 Figure 5 Maximum Out of Band Tx Line Energy Limits 1.5.8 Transmit Output Buffer This buffer amplifier, connected to the TXN, TXO and TXON pins, ...
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V23 / Bell 202 Modem 1.5.10 Tx/Rx UART This block connects the µC, via the ‘C-BUS’ interface, to the received data from the FSK Demodulator and to the transmit data input to the FSK Modulator. As part of this function, ...
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V23 / Bell 202 Modem Received data from the FSK Demodulator goes into the receive part of the UART block, where it is handled in one of two ways depending on the setting of bit 7 of the FSK MODE ...
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V23 / Bell 202 Modem 1.5.11 ‘C-BUS’ Interface This block provides for the transfer of data and control or status information between the CMX624’s internal registers and the µC over the ‘C-BUS’ serial bus. Each transaction, see Figure 7, consists ...
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V23 / Bell 202 Modem 1.5.12 ‘C-BUS’ Registers Write Only ‘C-BUS’ Registers Addr Reg. 7 $01 RESET N/A FSK mode: TXON o/ V. Off $E0 SETUP 1 = Bell 202 Mode: Tone ...
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V23 / Bell 202 Modem 1.6 Application Notes 1.6.1 Line Interface A line interface circuit is needed to provide dc isolation between the modem and the line, to perform line impedance termination, and to set the correct transmit and receive ...
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V23 / Bell 202 Modem In the transmit direction, the level on the 4-wire line is determined by the level at the TOP pin, the gain of the Output Buffer Amplifier, a loss of nominally 6dB due to the line ...
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V23 / Bell 202 Modem 1.6.2 Ring Detector Interface Figure 9 shows how the CMX624 may be used to detect the large amplitude Ringing signal received at the start of an incoming telephone call. The ring signal is usually applied ...
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V23 / Bell 202 Modem If the time constant of R24 and C22 is large enough then the voltage on RT will remain below the threshold of the 'B' Schmitt trigger for the duration of a ring cycle. The time ...
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V23 / Bell 202 Modem 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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V23 / Bell 202 Modem 1.7.1.3 Operating Characteristics For the following conditions unless otherwise specified 2.7V at Tamb = 25°C and V DD Xtal Frequency = 3.579545MHz DC Parameters I (Zero Power mode) DD (Running, TXON o/p Off, ...
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V23 / Bell 202 Modem DTMF Transmitter Level at TOP pin; tones in High Group Twist (level of High Group tones WRT level of Low Group tones) Tone frequency accuracy (worst case) Tx Filter and Output Buffer Change in level ...
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V23 / Bell 202 Modem Rx Energy Detector ‘Off’ to 'On' Threshold Level (FSK) ‘Off’ to 'On' Threshold Level (Call Progress) Hysteresis (measured 'Off' to 'On' Time (Figure 4 Teon): 1200bps Rx mode 75/150bps Rx mode ...
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V23 / Bell 202 Modem 3.5 3 2.5 2 Vin 1.5 1 0.5 0 2.5 Figure 11 Typical Schmitt Trigger Input Voltage Thresholds vs. V 2003 CML Microsystems Plc Figure 10 ‘C-BUS’ Timing 3 3.5 4 4.5 Vdd 23 ...
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V23 / Bell 202 Modem 1.7.2 Packaging Figure 12a 24-pin SOIC (D2) Mechanical Outline: Order as part no. CMX624D2 Figure 12b 24-pin SSOP (D5) Mechanical Outline: Order as part no. CMX624D5 2003 CML Microsystems Plc 24 CMX624 D/624/7 ...
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... V23 / Bell 202 Modem Figure 12c 24-pin DIL (P4) Mechanical Outline: Order as part no. CMX624P4 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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