Medical Electronics Symposium Conference Proceedings


Authors: Keith M. Sellers and John M. Radman
Company: Trace Laboratories, Inc.
Date Published: 1/31/2008   Conference: Medical Electronics Symposium

Abstract: Ion Chromatography (IC) is the predominant instrument used in the determination of overall cleanliness of printed circuit boards (PCB) and assemblies (PCA) in the medical device industry. Cleanliness testing should be one of many steps in your quality assurance process and its importance is critical as a first step in predicting overall product reliability.

Cleanliness requirements used by our medical productbased customers will be presented and discussed as well as compared to those requirements present in the non-medical product based industry.

Most customers develop specifications for cleanliness testing on their own, but as a common thread, most of them reference the use of IPC-TM-650, method 2.3.28A – “Ionic Analysis of Circuit Boards, Ion Chromatography Method” as the testing procedure. Whether known or not, other ion chromatography-based cleanliness test methods are available for use, specifically those from Delphi Automotive Systems and the US military. Although major differences are not present when comparing the methods, one striking difference is present: the solvent extraction matrix.

Overall, DI water and isopropyl alcohol / DI water solutions appear to be the matrices of choice. But why? And more importantly, which is the “best” matrix to choose? And does it really matter which matrix is chosen?

This presentation covers an internal study focused on determining the affects, if any, of the solvent extract matrix selection on the cleanliness results of a given sample. Additional relevant topics will also be addressed and discussed. Specifically, if differences are present, do these differences show any trends between the different matrices that may help in explaining why one matrix should be used instead of another? And also, should the products’ end use have any determining factor in which matrix is selected?

Key words: Ion Chromatography, IC, cleanliness, PCB, PCA

Members download articles for free:

Not a member yet?

What else do you get when you join SMTA? Read about all of the benefits that go along with membership.

Notice: Sharing of articles is restricted to just your immediate work group. Downloaded papers should not be stored on an external network or shared on the internet.


SMTA Headquarters
6600 City West Parkway, Suite 300
Eden Prairie, MN 55344 USA

Phone +1 952.920.7682
Fax +1 952.926.1819