Description
The MT89L85 Enhanced Digital Switch device is an upgraded 3-volt version of the MT8985 Digital Switch. It is pin compatible with the MT8985 and retains all of the MT8985s functionality. The enhanced digital swtich is designed for switching PCM-encoded voice or data, under microprocessor control, in digital exchanges, PBXs and any ST-BUS/MVIP environment. It provides simultaneous connections for up to 256 64kb/s channels.

Features
• 3.3 volt supply
• 5V tolerant inputs and TTL compatible outputs
• 256 x 256 channel non-blocking switch
• Programmable frame integrity for wideband channels
• Automatic identification of ST-BUS/GCI interface backplanes
• Per channel tristate control
• Patented message mode
• Non-multiplexed microprocessor interface
• Available in PLCC-44 and SSOP-48 packages
• Pin compatible with MT8985 device
• Low power consumption

Applications
• Medium size digital switch matrices
• Hyperchannel switching (e.g., ISDN H0)
• ST-BUS/MVIP™ interface functions
• Serial bus control and monitoring
• Centralized voice processing systems
• Data multiplexer