论文部分内容阅读
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。
Based on the 0.35μm BCD process, an over-temperature protection circuit is designed for use in automotive local interconnect (LIN) transceiver chips. In the ordinary two-stage comparator introduces a simple positive feedback, to achieve the temperature hysteresis characteristics, to avoid the circuit in the flip temperature threshold point thermal oscillation. Using the BJT voltage proportional to the absolute temperature (PTAT) voltage and the absolute temperature is inversely proportional to (CTAT) voltage comparison, the pressure difference between the two changes with temperature fast, the output control signal containing over-temperature decision to jump Small temperature, conversion speed, can achieve over-temperature protection of the chip lock. The simulation results show that the temperature is + (t +) = 159.4 ℃, the transition temperature from low level to high level of the output signal is only 0.1 ℃, and the heat transfer rate is 50 V / ° C, reverse flip (shutdown) temperature t- = 147.4 ° C, with a temperature hysteresis of 12 ° C. Circuit in the power supply voltage changes can be stable and reliable work to meet the automotive applications.