MT8889C Integrated DTMF Transceiver with Adaptive Micro Interface Data Sheet July 2008 Features Central office quality DTMF transmitter/receiver Ordering Information Low power consumption MT8889CE 20 Pin PDIP Tubes MT8889CS 20 Pin SOIC Tubes High speed adaptive micro interface MT8889CN 24 Pin SSOP Tubes MT8889CE1 20 Pin PDIP* Tubes Adjustable guard time MT8889CS1 20 Pin SOIC* Tubes MT8889CN1 24 Pin SSOP* Tubes Automatic tone burst mode MT8889CSR 20 Pin SOIC Tape & Reel MT8889CSR1 20 Pin SOIC* Tape & Reel Call progress tone detection to -30 dBm *Pb Free Matte Tin -40C to +85C Applications Credit card systems The receiver section is based upon the industry Paging systems standard MT8870 DTMF receiver while the transmitter Repeater systems/mobile radio utilizes a switched capacitor D/A converter for low distortion, high accuracy DTMF signalling. Internal Interconnect dialers counters provide a burst mode such that tone bursts Personal computers can be transmitted with precise timing. A call progress filter can be selected allowing a microprocessor to analyze call progress tones. Description The MT8889C utilizes an adaptive micro interface, The MT8889C is a monolithic DTMF transceiver with which allows the device to be connected to a number call progress filter. It is fabricated in CMOS technology of popular microcontrollers with minimal external logic. offering low power consumption and high reliability. D0 Data Row and D/A Transmit Data Bus D1 Column TONE Converters Register Buffer Counters D2 D3 Status Interrupt Tone Burst Register Control Gating Cct. Logic Logic IRQ/CP Control IN+ + Dial Register Tone - High Group IN- A Digital Filter DS/RD Filter Algorithm GS and Code Control I/O CS Low Group Converter Register Control OSC1 B Filter Oscillator R/W/WR Circuit OSC2 RS0 Control Receive Data Steering Bias Logic Register Logic Circuit V V V ESt St/GT DD Ref SS Figure 1 - Functional Block Diagram 1 Zarlink Semiconductor Inc. Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc. Copyright 2003-2008, Zarlink Semiconductor Inc. All Rights Reserved.MT8889C Data Sheet Functional Description The MT8889C Integrated DTMF Transceiver consists of a high performance DTMF receiver with an internal gain setting amplifier and a DTMF generator, which employs a burst counter to synthesize precise tone bursts and pauses. A call progress mode can be selected so that frequencies within the specified passband can be detected. The adaptive micro interface allows microcontrollers, such as the 68HC11, 80C51 and TMS370C50, to access the MT8889C internal registers. IN+ 1 24 VDD 20 IN+ 1 VDD 2 23 IN- St/GT 2 NC NC IN- 19 St/GT 5 25 22 GS 3 ESt VRef GS 3 18 ESt 6 24 NC 21 VRef 4 D3 VSS 4 17 7 23 NC VRef D3 5 20 D2 VSS 5 16 OSC1 8 22 D3 VSS D2 19 OSC1 6 D1 15 OSC2 9 21 D2 OSC1 6 D1 18 OSC2 7 D0 14 NC 10 20 OSC2 7 D0 17 D1 NC 8 NC 13 11 19 D0 TONE 8 IRQ/CP NC 9 16 NC NC 12 TONE R/W/WR 9 10 15 DS/RD IRQ/CP 11 14 CS 10 RS0 R/W/WR 11 DS/RD 13 CS 12 RS0 20 PIN PLASTIC DIP/SOIC 24 PIN SSOP 28 PIN PLCC Figure 2 - Pin Connections Pin Description Pin Name Description 20 24 28 11 1 IN+ Non-inverting op-amp input. 22 2 IN- Inverting op-amp input. 33 4 GS Gain Select. Gives access to output of front end differential amplifier for connection of feedback resistor. 44 6 V Reference Voltage output (V /2). Ref DD 55 7 V Ground (0V). SS 6 6 8 OSC1 DTMF clock/oscillator input. Connect a 4.7 M resistor to VSS if crystal oscillator is used. 77 9 OSC2 Oscillator output. A 3.579545 MHz crystal connected between OSC1 and OSC2 completes the internal oscillator circuit. Leave open circuit when OSC1 is driven externally. 8 10 12 TONE Output from internal DTMF transmitter. 911 13 R/W (WR) (Motorola) Read/Write or (Intel) Write microprocessor input. TTL compatible. 10 12 14 CS Chip Select input. This signal must be qualified externally by either address strobe (AS), valid memory address (VMA) or address latch enable (ALE) signal, see Figure 14. 11 13 15 RS0 Register Select input. Refer to Table 3 for bit interpretation. TTL compatible. 12 14 17 DS (RD) (Motorola) Data Strobe or (Intel) Read microprocessor input. Activity on this input is only required when the device is being accessed. TTL compatible. 2 Zarlink Semiconductor Inc. 4 12 13 3 2 14 1 15 16 28 27 17 18 26 GS NC IN- IN+ VDD St/GT EST DS/RD TONE R/W/WR CS RSO NC IRQ/ CP