Description
The Mitel MH88400 Line Interface Circuit provides a complete audio and signalling link between audio equipment and central office. The functions provided by the MH88400 include 2-4 Wire conversion, loop seizure, external monitor phone switch hook status and ringing voltage and loop current detection. The device is fabricated as a thick film hybrid which incorporates various technologies for optimum circuit design, high voltage isolation and very high reliability.

Features
• FAX and Modem interface
• Suitable for V.29 FAX & V.22 bis Data
• Allows caller identification
• Variants match German, UK, 600Ω & 900Ω network impedances
• Isolation circuitry conforms to international PTT requirements
• Transformerless 2-4 Wire conversion
• Loop start operation
• Pulse and DTMF operation
• Accommodates external monitor phone
• Line state detection outputs:
    -loop current/ringing outputs
    -monitor phone switch hook
• Single +5V operation

Applications
Interface to Central Office for:
• DAA
• Modem
• FAX
• Answering Machine
• Terminal Equipment