几种运算放大器低温下性能的研究

A RESEARCH OF THE PERFORMANCE OF SOME OPERATIONAL AMPLIFIERS AT LOW TEMPERATURE

叙述了五种不同类型的有代表性的运算放大器在低温下性能的测试结果,测试内容包括噪声特性、开环增益和输入失调电压等。结果表明:大多数运算放大器在170°K 左右的性能可优于室温下的结果;同时,以 J—FET 为输入级的运算放大器还可在77°K 的低温下工作。

In many cases low noise operational amplifiers are often used as the preamplifiers of different kinds of detectors working at low temperature. It is an interesting question, If the operational amplifiers can be used at low temperature. If the anwser is positive then they can be mounted in the cryostat near detectors and it will be very favourable to reducing the turbulence and noise. So some typical operational amplifiers arc chosen for testing. The results are quite encouraging, most of the tested oper- ational amplifiers are working well at the temperaturer about 170K,Some of them are working even better than at room temperature. And most of the operational amplifiers with J-FET input stage can be operated even at low temperature of 77K.