Abstract: Based on CSMC(Central Semiconductor Manufacturing Corporation) 0.5μm CMOS process,a design of over—temperature protection circuit,which is applied in LIN transceiver,is proposed.The circuit includes comparator,and two types of voltage that are of different temperature characteristics are used as the input of the comparator.The output voltage is the output signal of the over—temperature protection circuit.Through simulation by Cadence Spectre,the results show that,the thermal shut—down temperature is 160℃,the thermal start temperature is 120℃ and the hysteresis range is 40℃.