Design Of Low Power MCU For Sensor Application

Currently,MCU as an important part of sensor has been widely used in various fields,such as automotive electronics,industrial control and aerospace.In accordance with the development of sensor technology,battery-operated devices and self-powered devices develop in sequence,which has a high requirement for the low-power consumption of MCU.In order to cut down the power consumption of the sensor,an investigation on the design of a low-power MCU for sensor application is presented in this dissertation.Based on RISC,Harvard architecture and two-stage pipeline,this dissertation introduces the design and the investigation of modules as following:clock module,program counter module,interrupt module,control hazards processing module,timer/counter module,storage space allocation module,power management module.To enhance stability of the system,gray counter,circuitry for generating non-overlapping clock and glitch-free clock switching circuit are used to build clock module.To improve extensibility of the chip,full adder in the program counter module is utilized to realize stack architecture.To avoid conflicts between instruction execution and interrupt response,a "dual-signal" response mechanism is proposed in the interrupt module.To reduce the chip area,the wake-up function of the power management module is implemented by interrupt mechanism.To improve the resolution of timer and reduce the average power consumption of sensor application,a novel edge synchronizer which makes the limit of data stabilization up to 0.75 cycles of the new clock domain is proposed.To reduce power consumption of MCU in working mode,an optimized scheme of power management module is proposed in this dissertation.This is applied to control program memory on the account of two-stage pipeline.Apart from this,an assembly language compiler is designed and a simulation platform is built.Then these modules of MCU are simulated based on NUVOTON 0.35?m 2P3M CMOS process.Simulation results show that the function of instruction is correct and the timing of module is consistent.Tape-out is carried out by foundry(Nuvoton Technology Corporation),followed by chip test.The test results show that:1)The instruction is executed normally.2)The function of novel edge synchronizer is correct and the resolution of timer is up to 0.5?s with a system frequency of 4MHz.3)When the supply voltage is 3.3V,the power consumption in high-speed and low-speed modes are reduced by 20.65%and 41.3%respectively.