互补MOS-光耦合式多点切换器

 多点切换器是现代自动测控技术中的一个难点。本文介绍了一种由衬底引出的互补MOS模拟门作开关元件、双端出线的光耦合器作隔离屏蔽元件和由集成门作控制元件设计成的多点切换器。它的栅极泄漏电流影响可忽略,导通电阻只有10～30欧,噪声电平约±1微伏,能兼容高低电平的测量（±1～3200毫伏）;实现了模拟电路和控制电路的隔离屏蔽,能三线采样,抗干扰性强;切换时间短（微秒级）,可进一步集成化。它不仅可以解决试验现场低电平快速切换的困难,而且能使数据采集系统简单经济和通用性强。

A COMPLEMENTARY MOS-LIGHTCOUPLED MULTIPLEXER

Design of a multiplexer is a complicated task in modern automatic measurement and control systems, especially for sampling of low level signals on the spot. A complementary MOS-lightcoupled multiplexer is presented, in which complementary MOS analog gates drawn out from the substrate with a wire are used as switch components, lightcoupleddevices drawn out from two ends with wires - as isolate-shieldedcomponents and integrated gates- as control components. Its test is asuccess.The advantages of the multiplexer are summarized as follows:1.Its isolate-shielded performance is quite desirable, and it is capable of three line sampling and application in the spots with strong interference.2.The influence of grid leakage currents and peak interference can be eliminated. As its noise is about ±1μv, it can deal with low level signals.3.In a wide measurement range its ON-resistance is low and only 10 to 30 ohms when the input level is between +3 to - 3 volts.4.Its turn-on time is short, in the level of microseconds.5.It can be driven by TTL integrated gate and easy of further integration.