METHOD FOR TESTING QFP READ

摘要

(1) determining a longest lead tip of the quard flat package as a first post out of three posts; (2) determining a second post to be a lead tip having a smallest Z-axis slope at a cross point of an equation parallel with an equation passing the center of gravity from a post and an equation vertical with an equation passing the center of gravity from the first post; (3) determining a third post to be a lead tip having a smallest slope by obtaining Z value corresponding to a cross point of a linear equation passing the first and second posts and a linear equation of all the lead tips which is vertical with the former equation; and (4) repeating until the third post includes the center of gravity and comparing with the data of a good package so as to determine the quality.