Circuits Assembly - February 2008 - (Page 38)

Test and Inspection The Fixture Dilemma When switching platforms, do you start with new fixtures, or use adapters? hen a new in-circuit test system or ICTrelated technology comes out and you have a stack of legacy fixtures on your plant floor, how do you decide whether to convert to a new test system or fixture to encompass the technology? The governing decision should be heavily weighted to minimize risk while maximizing benefit. That strategy is obvious, I suspect, but the solution or configuration that actually minimizes risk and maximizes benefit is not so straightforward. In some cases, the OEM no longer supports legacy ICT systems. This seems like a good reason to migrate to a new platform or even switch suppliers, but even that is not straightforward. When you consider the investment required to buy a new tester and re-fixture all your existing products, converting becomes very expensive. This is why the broker market and the availability of support on a system not supported by the OEM may warrant staying on the legacy platform. That said, new testers mean new capabilities; thus, investing in a new test system may be the right answer. Switching entails considering whether to start from scratch with new fixtures or leverage an adapter. Overall, viewing your run rate, board complexity, number of testers and the cost to sustain a system using a third-party organization, along with the desired test coverage results, will help drive the decision. There may be extraneous factors forcing the change to a new platform also, such as the manufacturing parent company standardizing on an operating system that the legacy tester does not support. So, if forced to a new system, how do you then choose between an adapter and a new fixture? An adapter will typically not permit you to take advantage of new capabilities and coverage on a test system. It simply transfers the same capability to the new system. Therefore, a good rule-of-thumb on when to use an adapter is when you have older or more established board technology, a lower runrate, or you do not need to leverage new capabilities from recent technological or system advances to get good information from your test. One might also consider the state of the fixture under consider- W Older board technology or low run-rates are wellsuited to adapters. Stacy Kalisz Johnson is Americas marketing development manager at Agilent (agilent. com); stacy_johnson@ agilent.com. ation. Fixtures eventually wear out and need to be replaced. If the remaining fixture life is not long, then investing in an adapter versus a new fixture may not have a good return. Another important consideration: Using an adapter does not mean a straightforward conversion. Programming and debug time are still required. It might take a day or two or several weeks to confirm all is set with the new program. A good time to switch to a new fixture may be when you want to take advantage of new capabilities, or if minimizing crosstalk is a motivator, switching to a short-wire or wireless fixture may be warranted. Throughput might also be a consideration as new fixture or technology capabilities may positively impact the overall line rate. Obviously, when ramping a new product, a new fixture would be used. Possibly the most compelling reason to switch to a new fixture to encompass new capabilities is in the event of field returns. Field returns are extremely costly, and the ROI for a new fixture would be felt instantly, if even a single field return were eliminated. In general, there is no catchall solution, and in fact, most ICT users would implement a combination of solutions. The old tester may be kept for warranty return rate analysis, and potentially low run rate, low technology products would stay on that system. A new system might be introduced for a new product launch, or potentially a new system with an adapter fixture (plus program/debug) may be used for a board that has a high run rate. There may even be scenarios that reverse this completely, where a high run-rate product stays on the old platform while lower run rates migrate to a new platform or a fixture adapter setup on a different system. While there is no right answer and in fact, no single answer, it is interesting to explore the considerations going into the decisions that drive these markets. In the end, balancing risk against the cost and return is the goal, and it will be a companyspecific decision. Au note: Thank you Jeff Bossenbroek and Jon O’Connell from Agilent Technologies Inc.; Neil Adams, Russ Carter, and Stuart Eickhoff from Circuit Check; and Corey Schwartz from QXQ for consult during the preparation of this column. ■ circuitsassembly.com 38 Circuits Assembly FEBRUARY 2008 http://agilent.com http://agilent.com http://circuitsassembly.com

Table of Contents Feed for the Digital Edition of Circuits Assembly - February 2008

Circuits Assembly - February 2008 Contents Caveat Lector Letters Industry News Market Watch Global Sourcing Better Manufacturing Maximizing Lean Copper As a Viable Solution for IC Packaging Embedded Active Components for High-Rel Products Cover Story: XRF Equipment As a RoHS Screening Tool Tech Tips Selective Soldering Test and Inspection Process Doctor Pb-Free Lessons Learned Product Spotlight Ad Index Assembly Insider Technical Abstracts

Circuits Assembly - February 2008

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.