基于高压BCD工艺的内集成自举电路

Internally Integrated Bootstrap Circuit Based on High Voltage BCD Technology

设计了一款基于高压BCD工艺的内集成MOS自举电路,将其应用于高压集成电路(HVIC)。对传统的内集成MOS自举电路进行改进,该改进版内置MOS自举电路集成升压控制模块,实现在HVIC通电后屏蔽HVIC输入信号,并通过集成的升压电路将自举电容电压充到预期值,解决了以往使用传统的内置MOS自举功能时,因充电速度慢、充电电压低所导致的触发HVIC欠压保护和电器频繁停机问题。基于SMIC 3μm BCD工艺对所设计的自举电路的HVIC进行流片验证。测试结果表明,升压电路将HVIC供电电压从15 V升高至16.4 V,自举电容电压可达到预期值,同时实现了替代外接自举二极管或通过SOI工艺内置自举二极管的自举功能。

An internally integrated MOS bootstrap circuit based on high voltage BCD technology was designed and applied to high voltage integrated circuit(HVIC).The conventional internally integrated MOS bootstrap circuit was improved.The improved built-in MOS bootstrap circuit integrated a boost control module to shield the HVIC input signal after the HVIC was powered on,and the bootstrap capacitor was charged to the expected voltage through the integrated boost circuit,which solved the problem of triggering HVIC undervoltage protection and frequent shutdown of electrical appliances caused by slow charging speed and low charging voltage when the conventional built-in MOS bootstrap function was used.Based on the SMIC 3μm BCD technology,the designed HVIC of the bootstrap circuit was fabricated and verified.The test results show that the boost circuit boosts the HVIC supply voltage from 15 V to 16.4 V,and the bootstrap capacitor voltage can reach the expected value.At the same time,it realizes the bootstrap function of replacing the external bootstrap diode or the built-in bootstrap diode through the SOI process.