.32-bit Microprocessor Temperature Control Unit Design

This paper designed a microprocessor used as a thermal assist unit (TAU).The TAU is an on-chip sensor that provides thermal control by periodically comparing the chip junction temperature against user-programmed thresholds, and generating a thermal management interrupt if the threshold values are crossed. The TAU also enables the user to determine the junction temperature through a software successive approximation routine.By compare with MOSFET device,bipolar transistors also have properties that could be used for temperature sensing but they have much greater performance on sensing the signal.That's why bipolar transistor are preferred to design temperature sensors now. Since CMOS processing is the most extensively manufactured technology in many companies, the intergration of temperature sensors in CMOS technologies is consider to be allowing digital signal processing in the system on chip. However, the temperature sensors still suffer from several specific problems, which are not compatible with CMOS processing, such as offset temperature, drift and process mismatch. Research of temperature sensors with high accuracy, low power dissipation and low expense becomes a vital subject in temperature sensor field.The on-chip thermal assist unit (TAU) is composed a thermal sensor, a digital-to-analog converter (DAC), a comparator, a thermal decoder, control logic, and three dedicated registers.HSPICE simulation approves that TAU can generate the thermal interrupt when the junction temperature jumps over the threshold values less than 2℃. The TAU works under temperature of 0℃~124℃.The research achievements can be used for some high accuracy applications, just as microprocessor, air condition, medicine instuments and self-checking systems, etc. In a word, it has a significant research meanings and extensive application prospect.