In Circuit Test (ICT) testing and ICT tester system manufacturers
In-Circuit Test (ICT) is a method of testing printed circuit board (PCB) assemblies for manufacturing defects. It's a comprehensive test that checks for faults in individual components, such as resistors, capacitors, and integrated circuits, as well as for opens, shorts, and other defects in the PCB's conductive traces. ICT is widely used in electronics manufacturing to ensure the quality and reliability of PCB assemblies before they are shipped to customers. Let us understand In Circuit Test (ICT) testing basics and explore ICT tester system from popular vendors and manufacturers.
ICT Test System Components
Following are the common components usually found in ICT tester system.
➨Test Fixture: The test fixture is a specialized interface between the PCB assembly being tested and the ICT tester. It typically consists of a bed of nails or pogo pins that make contact with the test points on the PCB. The fixture also includes circuitry for applying test signals and measuring responses.
➨ICT Tester Hardware: The ICT tester hardware comprises the main unit responsible for generating test signals, applying them to the PCB under test, and measuring the responses. It includes analog and digital signal generators, voltage and current measurement circuits, and other hardware components necessary for testing.
➨ICT Tester Software: The software controls the operation of the ICT tester hardware and interprets the test results. It typically includes a user interface for setting up tests, defining test parameters, and analyzing results. The software may also provide features such as fault diagnosis, reporting, and data logging.
➨Test Probes and Accessories: Various probes and accessories are used in conjunction with the ICT tester system to perform specific tests and measurements. These may include specialized probes for testing specific types of components, adapters for testing different PCB form factors, and other accessories for ensuring proper contact and alignment during testing.
ICT Testing Process
➨Test Program Development: Before conducting ICT testing, a test program needs to be developed.
This involves creating a set of test procedures and instructions for the ICT tester to follow during testing.
The test program specifies the tests to be performed, the test conditions, and the expected responses.
➨PCB Setup: The PCB assembly to be tested is placed in the test fixture, ensuring proper alignment and contact with the test probes. The fixture is designed to accommodate the specific form factor and layout of the PCB.
➨Test Execution: The ICT tester applies test signals to the PCB assembly through the test probes and measures the responses. The tests typically include checks for opens, shorts, component values, and other electrical characteristics. The tester may also perform functional tests to verify the proper operation of specific circuits or features.
➨Data Analysis: The ICT tester software analyzes the test results and compares them to the expected responses defined in the test program. Any discrepancies or failures are flagged as defects, and diagnostic information may be provided to aid in troubleshooting and repair.
➨Fault Diagnosis and Repair: If defects are detected during testing, the PCB assembly may undergo further diagnosis to identify the root cause of the failures. Once the faults are identified, they can be repaired or rectified, either manually or through automated repair processes.
➨Reporting and Documentation: After testing is complete, a report summarizing the test results, including any defects found and their locations, is generated. This report provides valuable feedback to the manufacturing process and may be used for quality assurance purposes and customer documentation.
In-Circuit Test (ICT) system manufacturers
Following features are available in latest ICT test systems .
• Boundary scan
• Automated probing
• Optical inspection
• Functional testing
Other than above factors, selection of ICT (In-Circuit Test) system depends on type of product. Any product design need to have testability associated with it. DFT (Design for testability) will add certain testability features in the design of the product. Hence it is easy to develop and apply manufacturing tests for the DUT hardware. Following is the list of ICT tester manufacturers.
|• Does parallel test of multiple boards
• zero footprint design
• productivity equivalent to 2 or more MDA/ICT systems
|• electrical measurements of components
• can probe 2 test points about 20 mils closer using angular probe concept
|Test and Research India Pvt. Ltd
|TR5001T SII TINY
|• full featured ICT solution
• programmable DUT power supply
• parallel testing of DUTs with USB ports
|Kyoritsu Electric India Pvt.Ltd.
|• One of the fastest MDA(Manufacturing defect analyzer) in the test and measurement industry
• easy in maintenance
|Flying Scorpion FLS980Dxi
|• programmable probe angle from +6 to -6 degrees
Resolution of +/-0.1 micron
|Flying Probe S2
|• highest performance in measurement with accuracy
• 4 times faster on board programming
|• low cost fixing
• ultimate signal quality
• control path for board alignment
Conclusion : Overall, ICT testing is an essential step in electronics manufacturing for ensuring the quality and reliability of PCB assemblies. By detecting defects early in the production process, ICT helps minimize scrap, rework and field failures, ultimately improving product quality and customer satisfaction.