一种快速转换的过温保护电路  

A Fast-Transition Over-Thermal Protection Circuit

作　　者：张专[1,2] 程新红[1] 俞跃辉[1] 王坤[1] 

机构地区：[1]中国科学院上海微系统与信息技术研究所汽车电子工程中心,上海200050 [2]上海科技大学物质科学与技术学院,上海200031

出　　处：《半导体技术》2016年第1期22-26,共5页Semiconductor Technology

基　　金：国家科技重大专项资助项目(2012ZX02503-003)

摘　　要：基于0.35μm BCD工艺设计了应用于车用本地内联网(LIN)收发器芯片内的过温保护电路。在普通两级比较器上引入简单正反馈,实现了温度的滞回特性,避免电路在翻转温度阈值点产生热振荡。利用三极管(BJT)产生的与绝对温度成正比(PTAT)电压和与绝对温度成反比(CTAT)电压进行比较,两者的压差随温度变化快,输出的包含过温判定的控制信号跳转温区小,转换速度快,能实现对芯片的过温锁定保护。利用Cadence Spectre软件对所设计的电路进行仿真,结果表明,正翻转(开启)温度t+=159.4℃,输出信号的由低电平向高电平跳转温区仅为0.1℃,热转换速度为50 V/℃,逆翻转(关闭)温度t-=147.4℃,具有12℃的温度滞回量。电路在电源电压变化时能稳定可靠的工作,可满足汽车电子的应用需求。An over-thermal protection circuit for the automobile local interconnect network（ LIN）transceiver was designed based on 0. 35 μm BCD technology. To achieve temperature hysteresis characteristics and avoid thermal oscillation at turn temperature threshold,a simple positive feedback was introduced to the two-stage comparator. It was achieved by the comparison of proportional to absolute temperature（ PTAT） voltage and complementary to absolute temperature（ CTAT） voltage of BJT. The voltage difference of the PTAT voltage and CTAT voltage varied fast with the temperature,therefore the transition span of output signal which imported over-temperature determination was small and the output signal transformed quickly to provide over-thermal lock-out protection for the chip. The circuit was simulated by using Cadence Spectre software. And the simulation results demonstrate that activation temperature t＋is159. 4 ℃,deactivation temperature t-is 147. 4 ℃,temperature hysteresis is 12 ℃,the transition span from high level to low level is 0. 1 ℃ and thermal transition rate is 50 V / ℃. In addition,the circuit can work stably and reliably when the power supply voltage swings. In conclusion,it can meet the application requirements of automotive electronics.

关 键 词：过温保护 温度滞回 热振荡 热转换速度 汽车电子 

分 类 号：TN433[电子电信—微电子学与固体电子学]