MH88400

® MH88400 Line Interface Circuit Preliminary Information Features FAX and Modem interface Suitable for V.29 FAX & V.22 bis Data Allows caller identification Variants match German, UK, 600Ω & 900 Ω 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 ISSUE 1 April 1995 Ordering Information MH88400-1 14 Pin DIL Package MH88400-2 14 Pin DIL Package MH88400-3 14 Pin DIL Package 0° C to 70° C 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. Variants are provided to meet German (-1) and UK (-3) and general 600 Ω (-2) line impedance (see section on Line Impedances). Isolation Barrier Power Supply Applications Interface to Central Office for: DAA Modem FAX Answering Machine Terminal Equipment Transformer Isolation VDD AGND TIP RING Active Termination OptoIsolation Op...