Testonica delivers technology for testing BGAs Power/Ground solder joints without X-Ray

Testing solder joints of BGA packages upon PCB assemblies is a challenging task unless X-Ray equipment is available. In numerous cases X-Ray (AXI) is too costly while functional test (FCT) and IEEE 1149.1 Boundary Scan (JTAG) cannot catch open defects in power or ground nets. During Nordic Test Forum (NTF'2019) conference in Tallinn this week, Testonica has presented a ground breaking technology capable to detect defects in Power Delivery Network (PDN) of FPGA-based products using no AXI.

The operating margins of PDNs are progressively reduced due to increasingly strict requirements of high-performance applications. As a consequence, even otherwise negligible manufacturing quality issues (Marginal Defects) and process variations in the PDN may create latent problems that would manifest in specific conditions compromising the overall system performance or even causing malfunctions.

Nowadays, the increasing demand for high-performance systems produces significant growth in usage of FPGAs for different applications thanks to their flexibility and high level of parallelism. In collaboration with researchers from TalTech and Politecnico di Torino, Testonica has developed a new FPGA-based non-intrusive method to detect Marginal Defects in a PCBA PDN. The method is based on a monitoring circuit that measures signal delays caused by PDN variations and thus detects relevant anomalies.

In future, our embedded instrumentation technology will be able to pinpoint the problematic PCBA area including particular traces and solder balls affected by power integrity issues. Today, the outlier products (in which anomalies have been detected) need to be further inspected for actual defects by X-Ray equipment. In this way, the novel technology allows to carefully prescreen devices requiring X-Ray inspection significantly reducing the AXI workload and related costs.

The novel technology's theoretical background was published earlier this year in a scientific publication: "A new FPGA-based Detection Method for Spurious Variations in PCBA Power Distribution Network" by S. Odintsov, L. Bozzoli, C. De Sio, L. Sterpone, and A. Jutman.