The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 19, 2002
Filed:
Jul. 18, 2000
Rahul V. Gune, Nonthaburi, TH;
Youthachai Bupparit, Nonthaburi, TH;
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
A method and apparatus are provided for fast and thorough inspection of tray stacks for misplaced ICs that is not susceptible to human error and prevents shipment of damaged ICs to users. Embodiments include an inspection apparatus, such as at a conventional strapping machine, comprising a number of photoelectric sensors near the corners of the trays of the stack. The sensors are moved, as by pneumatic cylinders, such that each sensor scans all of the trays in the stack, one tray at a time, while directing a beam of light at the tray and receiving a quantity of the light of the beam reflected from the stack. The received quantity of light is compared to an expected reference quantity of light corresponding to a tray without any misplaced ICs, and a signal is generated and sent to a processor based on this comparison. If the received quantity of light closely matches the reference quantity, a signal is sent to the processor indicating the tray has no misplaced ICs, and the processor enables the strapping operation. On the other hand, if the received quantity of light does not closely match the reference quantity, a signal is sent to the processor indicating a tray has a misplaced IC, and the processor generates an alarm signal, such as a red light, and disables the strapping operation. The operator can then correctly position the misplaced IC in its tray. The inspection procedure is then repeated, and the tray stack is strapped for shipping if no other misplaced ICs are found. Since performance of the strapping operation is prevented if a misplaced IC is found, damage to ICs incurred by strapping tray stacks with misplaced ICs, such as bent leads, is eliminated, and shipment of damaged ICs to customers is prevented.