Description
The Mitel MH88500 Subscriber Line Interface Circuit provides a complete interface between the telephone line and a speech switch requiring only single bidirectional switch per crosspoint. The functions provided by the MH88500 include bidirectional differential to single ended conversion in the speech path, line battery feed, ringing feed and loop and dial pulse detection. The device is fabricated as a thick film hybrid in a 20-pin ‘single-in-line’ package allowing optimum circuit board packing density.

Features
• Differential to single ended conversion
• No transformers required
• Minimum installation space
• Off-Hook detection and LED indicator drive
• Relay drive output
• Battery and ringing feed to line
• Logic interface: MUTE, OFHK, RC
• Mute of incoming audio
• Dial pulse detection
• Voltage surge protection

Applications
Line Interface for:
• PABX
• Intercoms
• Key Systems