M-8888

· Advanced CMOS technology for low power consumption and increased noise immunity
· Complete DTMF transmitter/receiver in a single chip
· Standard 8051, 8086/8 microprocessor port
· Central office quality and performance
· Adjustable guard time
· Automatic tone burst mode
· Call progress mode
· Single +5 Volt power supply
· 20-pin DIP and SOIC packages
· 2 MHz microprocessor port operation
· Inexpensive 3.58 MHz crystal

· Paging systems
· Repeater systems/mobile radio
· Interconnect dialers
· PBX systems
· Computer systems
· Fax machines
· Pay telephone
· Credit card verification

The M-8888 is a complete DTMF Transmitter Receiver that features adjustable guard time, automatic tone burst mode, call progress mode, and a fully compatible 8051, 8086/8 microprocessor interface. The receiver portion is based on the industry standard M-8870 DTMF Receiver, while the transmitter uses a switched-capacitor digital-to-analog converter for lowdistortion, highly accurate DTMF signaling. Tone bursts can be transmitted with precise timing by making use of the automatic tone burst mode. To analyze call progress tones, a call progress filter can be selected
by an external microprocessor.