It is not infrequent that commercially available standard IC components do not fit a particular application as they are specified. Often, however, a standard device selected to tighter limits will work. Thereupon, the IC manufacturer may be requested to supply a specially tested device. The usual chain of events for a selected part is as follows: A specification is sent to the manufacturer with a request for quote. It is evaluated at the manufacturer for feasibility, yield, and testing requirements. Then price and delivery are quoted to the customer. (Sometimes this route is shortened by calling the manufacturerÐbut this does not always work.) Some insight into the IC design and IC testing can help both the manufacturer and IC user with special selection. Proper specification helps the manufacturer test as well as reduce IC costs. Ambiguous or impossible specs will usually result in the return of the specification to the customer for clarification and delay the delivery of the required parts. The manufacturer is usually familiar with the product and production spread of devices. Further, test equipment is available for measuring parameters specified by the data sheet. In general, tighting selected data sheet parameters causes no problems. Further, no additional test equipment is needed for these testsÐonly the limits need be changed. Perhaps one of the largest problems is over-specification. Each tightened specification reduces the number of parts available to the specification. For example, tightening several specifications at once could result in a 1% or 0.1% yield; to supply 100 parts at this yield, between 10,000 and 100,000 parts might have to be tested, and that gets expensive.
声明:本文内容及配图由入驻作者撰写或者入驻合作网站授权转载。文章观点仅代表作者本人,不代表电子发烧友网立场。文章及其配图仅供工程师学习之用,如有内容侵权或者其他违规问题,请联系本站处理。 举报投诉
全部0条评论
快来发表一下你的评论吧 !