UM82C55A

The UM82C55A is a high performance CMOS version of the industry standard UM82C55A and is manufactured using a self aligned silicon gate CMOS process.It is a general purpose programmable I/O device which may be used with many different microprocessors.Static CMOS circuit design ensures low operating power,TTL compatibility of VIH=2.0 volts over the industrial temperature range and bus hold circuitry eliminates the need for pull-up resistors.

Features of the UM82C55A are:(1)pin compatible with NMOS 8255A;(2)24 programmable I/O pins;(3)fully TTL compatible;(4)bus-hold circuitry on all I/O ports eliminates pull-up resistors;(5)high speed,no "wat state" operation with 8MHz;(6)direct bit set/reset capability;(7)enhanced control word read capability;(8)single 5V power supply;(9)2.5mA drive capability on all I/O port outputs;(10)low standby current ICCSB=10A.

The absolute maximum ratings of the UM82C55A can be summarized as:(1):the supply voltage is +0.8 Volts;(2):the operating voltage range is +4V to +7V;(3):the input voltage applied is GND-2.0V to 6.5V;(4):the I/O pin voltage applied is GND-0.5V to VCC+0.5V;(5):the storage temperature range is -65 to 150;(6):the operating temperature range is 0 to +70;(7):the maximum power dissipation is 1Watt.