W78C31B

The W78C31B is a fast compatible microcontroller with a redesigned processor core without wasted clock and memory cycles. As a result, it executes every 8051 instruction faster than the original 8051 for the same crystal speed. Typically, the instruction executing time of W78C31B is 1.5 to 3 times faster than that of traditional depending on the type of instruction. In general, the overall performance is about 2.5 times better than the original for the same crystal speed. Giving the same throughput with lower clock speed, power consumption has been improved. Consequently, the W78C31B is a fully static CMOS design; it can also be operated at a lower crystal clock. The W78C31B contains In-System Programmable (ISP) 128 KB bank-addressed Flash EPROM; 4KB auxiliary Flash EPROM for loader program; on-chip 1 KB MOVX SRAM; power saving modes.

Features of the W78C31B can be summarized as:(1)8-bit CMOS microcontroller;(2)high speed architecture of 4 clocks/machine cycle;(3)Pin compatible with standard 80C52;(4)instruction-set compatible with MCS-51;(5)four 8-bit I/O Ports; Port 0 has internal pull-up resisters enabled by software;(6)one extra 4-bit I/O port, chip select;(7)dual 64KB In-System Programmable Flash EPROM banks (APFlash0 and APFlash1);(8)software programmable access cycle to external RAM/peripherals;(9)programmable watchdog timer.

The absolute maximum ratings can be summarized as:(1)DC power supply:-0.3 to +7.0 V;(2)input voltage:VSS-0.3 to VDD+0.3 V;(3)0 to +70°C;(4)-55 to +150°C.Note: exposure to conditions beyond those listed under absolute maximum ratings may adversely affect the life and reliability of the device.