Data transfer between moisture sensors

• US 7,272,896 B2
• Filed: 02/18/2005
• Issued: 09/25/2007
• Est. Priority Date: 02/18/2005
• Status: Expired due to Fees

• Current Assignee: Accu-Assembly Incorporated
• Original Assignee: Accu-Assembly Incorporated
• Inventors: Kou, Yuen-Foo Michael
• Primary Examiner(s): Rinehart; Kenneth
• Application Number:
  US11/061,589
• Publication Number:
  US 20060185187A1
• Time in Patent Office: 949 Days
• Field of Search: 235/375, 235/376, 438/15, 73/290.1, 73/73, 345/27, 34/60
• US Class Current: 34/527
• CPC Class Codes: G01R 31/2849 Environmental or reliability testing, e.g. burn-in or validation tests of individual semiconductors G01R31/2642; of printed circuits boards G01R31/2817; of IC's G01R31/2855

Abstract

A method of monitoring electrical component moisture exposure includes calculating a remaining floor life value for a group of electrical component containers and a first container, based on an associated first moisture sensor'"'"'s exposure to moisture; removing the first container from the group; creating an association between the removed first container and a second moisture sensor; and transferring the calculated remaining floor life value from the first moisture sensor for use with the second moisture sensor.

Claims

1. A method of monitoring electrical component moisture exposure, the method comprising:

calculating a remaining floor life value for a group of electrical component containers including a first container, based on an associated first moisture sensor'"'"'s exposure to moisture;

removing the first container from the group;

creating an association between the removed first container and a second moisture sensor; and

transferring the calculated remaining floor life value from the first moisture sensor for use with the second moisture sensor.

2. The method of claim 1 further comprising calculating, with the second moisture sensor, a remaining floor life value associated with the removed first container, based on the removed first container'"'"'s exposure to moisture.

3. The method of claim 2 further comprising using the transferred remaining floor life value associated with the group as an initial value for calculating the remaining floor life value associated with the removed first container.

4. The method of claim 2 further comprising:

recoupling the removed first container to the group of electrical component containers;

creating a new association between the recoupled first container and the first moisture sensor; and

transferring an updated remaining floor life value associated with the first container from the second moisture sensor to the first moisture sensor.

5. The method of claim 4 further comprising calculating, with the first moisture sensor, a remaining floor life value associated with the recoupled first container, based on the first moisture sensor'"'"'s exposure to moisture, wherein the calculating the remaining floor life of the recoupled first container comprises using the remaining floor life value transferred from the second moisture sensor as an initial value for the calculation.

6. The method of claim 2 further comprising determining suitability of an electrical component of the removed first container for exposure to reflow soldering conditions based on a value of remaining floor life associated with the removed first container calculated by the second moisture sensor.

7. The method of claim 6 wherein the suitability determination is accomplished as a component is being removed from the first container for placement onto a circuit board.

8. The method of claim 6 further comprising reflow soldering a suitable electrical component from the removed first container to a circuit board.

9. The method of claim 6 further comprising interrupting reflow soldering activities upon an unfavorable suitability determination.

10. The method of claim 1 further comprising, after removing the first container from the group, calculating a remaining floor life value associated the group.

11. The method of claim 1 wherein transferring the calculated remaining floor life value comprises transferring the remaining floor life value to a computer that is coupled to the second moisture sensor.

12. The method of claim 11 further comprising:

collecting moisture exposure data with the second moisture sensor, the data being associated with the removed first container'"'"'s exposure to moisture;

transferring the collected moisture exposure data to the associated computer; and

calculating a remaining floor life associated with the removed first container, based on the transferred moisture data and using the transferred remaining floor life value as an initial remaining floor life value.

13. The method of claim 1 further comprising, prior to calculating the remaining floor life value associated with the group, creating an association between the first moisture sensor and the group of electrical component containers.

14. The method of claim 13 wherein creating the association comprises securing the first moisture sensor to a container in the group.

15. The method of claim 1 wherein creating the association between the removed first container and the second moisture sensor comprises placing the removed first container in an area proximate the second moisture sensor.

16. The method of claim 1 further comprising setting the first moisture sensor to an initial remaining floor life value of 100% prior to calculating the remaining floor life value associated with the group.

17. The method of claim 1 wherein the calculating is performed periodically while the first container is associated with the first moisture sensor.

18. The method of claim 1 wherein the calculating is performed approximately continuously while the first container is associated with the first moisture sensor.

19. The method of claim 1 further comprising initiating the transferring by actuating a switch at the first moisture sensor.

20. The method of claim 19 further comprising positioning a magnetic element proximate the first moisture sensor to actuate the switch.

21. A system for monitoring electronic component moisture exposure, the system comprising:

a first moisture sensor associated with a group of electrical component containers; and

a second moisture sensor associated with an electrical component placement machine;

wherein the first moisture sensors is adapted to;

sense exposure to moisture over time;

calculate, based on the sensed exposure, a remaining floor life value of the associated group of containers; and

transfer an updated remaining floor life value of the associated group to the second moisture sensor upon removal of a first container from the associated group of containers.

22. The system of claim 21 wherein the first moisture sensor comprises a hall effect sensor adapted to activate the transfer of the updated remaining floor life value when a magnetic element is positioned proximate the first moisture sensor.

23. The system of claim 21 wherein the second moisture sensor is adapted to:

receive the transferred remaining floor life value from the first moisture sensor;

set, as an initial floor life value of the removed first container, the received remaining floor life value; and

periodically update the floor life value, over time, based on the removed first container'"'"'s exposure to moisture over time.

24. The system of claim 23 further comprising a computer coupled to the second moisture sensor, wherein the computer is adapted to determine suitability of components from the first tray for exposure to reflow conditions based on the updated floor life value.