Custom Layout of 8-bit RISC Microcontroller

Abstract

This thesis work presents custom layout of a 8-bit RISC microcontroller based on general architecture of the PIC 16f54 on AMI 0.6 submicron technology. The system designed is operative on all 33 general instructions of PIC 16f54 microcontroller. A modified architecture for branching is implemented. SRAM cells were used as general purpose memory. The operating frequency of the chip after simulation was 71.42 MHz (14nS clock period). This thesis also discusses the detailed system analysis and circuit behavior of the microcontroller. An 8-bit Arithmetic Logic unit, 32 word SRAM array, 12-bit wide Input Output port, two layered stack segment, a free running counter and its timer module were all custom designed using Cadence's Virtusio Integrated Circuit Design environment to maximize speed. Conditional branching instructions were reduced to a single cycle, one cycle less than the PIC 16f54 microcontroller. A complex three phased clock was used for non-pipelined design. A simulated version of the microcontroller was tested fully in the IRSIM simulator. Detailed simulation results are presented and discussed.