MT8920BE

The MT8920BE is a kind of ST-BUS Parallel Access Circuit (STPA) which provides a simple interface between Mitel's ST-BUS and parallel system environments. The typical applications of MT8920BE include: (1)parallel control/data access to T1/CEPT digital; (2)trunk interfaces; (3)digital signal processor interface to ST-BUS; (4)computer to Digital PABX link; (5)voice store and forward systems; (6)interprocessor communications. The device is available in 28 pin plastic DIP package.

There are some features of MT8920BE as follows: (1)high speed parallel access to the serial ST-BUS; (2)parallel bus optimized for 68000 mP (mode 1); (3)fast dual-port RAM access (mode 2); (4)access time: 120 nsec; (5)parallel bus controller (mode 3) - no external controller required; (6)flexible interrupt capabilities-two independent/programmable interrupt sources with auto-vectoring; (7)selectable 24 and 32 channel operation; (8)programmable loop-around modes; (9)low power CMOS technology.

What comes next is about the absolute maximum ratings of MT8920BE (voltages are with respect to ground (VSS) unless otherwise stated): (1)supply voltage, VDD: -0.3 to 7.0 V; (2)voltage on any I/O pin: -0.3 to VDD + 0.3 V; (3)current on any I/O pin, II/O: ±25 mA; (4)storage temperature, TST: -55 to 125; (5)package power dissipation, PD: Cerdip: 1000 mW; Plastic: 600 mW. Then is about the recommended operating conditions (voltages are with respect to ground (VSS) unless otherwise stated): (1)supply voltage, VDD: 4.75 V min, 5.0 V typ and 5.25 V max; (2)input high voltage, VIH: 2.4 V min and VDD V max for 400 mV noise margin; (3)input low voltage, VIL: 0 V min and 0.4 V max for 400 mV noise margin; (4)operating temperature, TA: -40 min, 25 typ and 85 max; (5)operating clock frequency, fCK: 4.096 MHz typ.