What exactly is connector design verification testing (DVT) (sometimes called a Design Qualification Test)? What does it measure? What kinds of conclusions can you make about the connector’s performance? Wasn’t DVT, along with immigration policies, China, and handling the Covid-19 pandemic among the most contentious topics during the 2020 Presidential debates?
Phil Eckert (Samtec’s Quality Engineering Manager) and Mark Shireman (Engineering Support Group/Test Lab Manager) share what, if any, conclusions you can glean about product performance from a connector design verification test.
By the way, when it comes to DVT, we can only speak for ourselves, but not other connector companies.
Here are Phil’s and Mark’s “10 Commandments” about connector design verification testing:
#1: Samtec DVT and Qualification tests are designed to measure the performance of the mated connector set in an application that is common to most of our customers. The experts got together at one point and determined that these series of tests simulate the environments and applications that most connectors will experience in their lifetimes.
#2: Samtec almost always tests to EIA-364 standards for the connector industry, or a slight variation thereof. Adhering to EIA-364 standards allows designers a common point of reference to compare results.
#3: Having said that, we understand that all applications are different; no two are exactly alike. Unfortunately, we can’t test for each unique application with respect to vibration, temperatures, shock, mating cycles, etc. Some applications are more harsh and demanding than others. But, as stated previously, the testing we do perform should be applicable in most situations.
#4: While connector manufacturers have the ability to perform custom testing to match a customer’s application, performing these tests can be time-consuming and expensive.
#5: We have testing that covers more specific applications and expectations; these usually test for harsher environments. Examples include Severe Environment Tests (SET), Extended Life Product testing (ELP), Solder Joint Reliability (here’s an example), and other tests like Mixed Flowing Gas.
#6: DVTs speaks nothing about our manufacturing capabilities, scrap, quality performance, or production efficiency.
#7: Most tests measure the change in Low Level Contact Resistance (LLCR) after exposure to harsh environments. Passing a test does not mean that corrosion was not present. A connector and contact system can pass testing (i.e., LLCR change) even if corrosion is present, or if there is relaxation in the contact beam from thermal exposure. In general, connectors pass testing if the LLCR change is less than 15 milliohms.
#8: The tests are passing or failing based on changes in LLCR, not on the initial LLCR readings. For the sake of these tests, it doesn’t matter if the initial LLCR is 45 milliohms or 15 milliohms.
#9: DVT is not a solder joint test. While the solder joints may be the focus of tests like SJR, most connector verification tests determine the integrity of the contact and terminal interface.
#10: Don’t extrapolate signal integrity performance from a DVT. Look at characterization reports for that (here’s an example of a recently completed High Speed Characterization Report).
#11: Here’s a bonus consideration: Design Verification, or Design Qualification tests, are sometimes called Accelerated Life Tests (ALT). We can’t reasonably test a product for five years, so as much as possible, we expose the products to conditions that simulate five years.
If you have questions please contact the Samtec Engineering Support Group.
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