Curve tracing is being adopted as a tool for electrically screening devices for evidence of counterfeiting as the need to detect fake or compromised IC chips continues. The process of curve tracing is an excellent choice for counterfeit screening because its electrical characterization ignores most functional details of the device and focuses on acquiring an “Electronic Signature” which is compared to signatures of other devices.
The Electronic Signature shows details of the input protection components of each pin, the supply current of the device when statically powered and not operating, and other DC characteristics listed on the datasheet that is directly measured and compared among devices to discover irregularities.
Counterfeit Screening is a Must
In 2016, the Department of Homeland Security reportedly seized $124M in counterfeit electronics. In 2020, the United States imported $343B of electronic equipment. Companies that sell IC devices, such as distributors, and users of these devices may need to screen IC chips they sell or purchase. In fact, the US government can hold liable its contractors or suppliers for allowing counterfeit or defective devices to enter the supply chain. Penalties can range from loss of the contract for unintentional sloppiness to actual imprisonment for intentional fraud. There is real commercial pressure to complete these tests thoroughly.
How Many Devices to Test?
When counterfeit screening your devices, one of the first issues to deal with is how many devices to test. This decision comes from an analysis of cost-to-test and risk of failure. You can choose to test a small sample of devices or test all the devices in a lot. Questions about minimum sample size and how to evaluate and weigh the results arise.
Who Requires 100% Test?
For Aerospace OEM manufacturers and suppliers, the requirement is at its highest. The penalties to airlines for the failure of even noncritical equipment like the in-flight entertainment system can be quite high. These organizations favor 100% testing where every individual device is evaluated before final application. The overhead to test the devices and evaluate the results is high but RTI has a ready solution. RTI’s flagship DataTrace Software enables Batch Testing, Batch Analysis, and Test Sequencer tools that make testing and analyzing sets of hundreds of devices possible and economical if 100% testing is in your plans.
Where is a Sample Size Applicable?
Representative of sample size vs margin of error. Source: wikimedia.org
For component distributors in the open market, the need to screen for counterfeits is also very important. The reputation of the distributor is paramount to making sales and finding new customers. For these situations, it is important to be economical with testing so that it does not add to the product cost and undermine the profits. The MultiTrace is scalable in pin count and power so it can find a good fit within the needs of these organizations and become a go-to tool for ongoing electrical tests.
RTI’s Curve Tracers for IC Counterfeit Screening
DataTrace Batch Comparison Results Screenshot
The MultiTrace test system quickly gains data and permanently saves it in a file per device. You can try a range of different test conditions (see post here) (another post here) to fine-tune the test sensitivity, time to test, and effort to test and analyze.
For smaller sample sizes, the results give a statistical view of the lot the devices came from. A typical test lot might be five or more devices at random per date code. You shouldn’t test fewer than five samples because, with two or three devices, you can end up with all three mismatched, or one of the three does not match. This does not hold enough statistical significance to draw a meaningful conclusion. With an odd number of five or more devices, you will always have a tiebreaker, and no matter what the combination of match and mismatch, you can make a judgment if the lot matches among itself. If the part was tested before, then comparison to historical lots gives even higher confidence the devices are electrically consistent with each other.
RTI is well-positioned to support organizations that want to use curve tracing as a nondestructive counterfeit screening tool. Our wide range of test system configurations and test fixture interfaces allows us to provide turnkey solutions.