What is In-Circuit Testing

In-circuit testing (ICT) is a performance and quality testing method for printed circuit boards (PCB). While there are many types of PCB testing, ICT covers essential testing capacities to help manufacturers determine whether their components and units function and meet the product specifications and capabilities. Understanding what in-circuit testing is, what it covers and its strengths can help you determine if it will handle testing your PCBs.

Basic Overview of ICT

ICT offers basic PBC testing for various manufacturing errors and electrical functions. While many manufacturers include highly skilled personnel and automated equipment, testing can help locate critical errors that maintain unit function and quality. This testing method combines custom-designed hardware with specifically programmed software to create highly specialized testing that works only for one PCB type.

ICT will test components individually, checking that each one is in the right place and meets the product and industry capacity and functionality. This testing method is an excellent way of ensuring that everything is where it needs to be, especially as units grow smaller.

While ICT can give you an idea of functionality, this is only for logic functionality. ICT involves testing each component in your unit individually to ensure they all function, allowing in-circuit testing methods to give manufacturers and engineers an idea of how units will function together.

Primary Types of ICT

When considering using a specific type of circuit testing like ICT, you will need to understand its particular processes and the kinds of tests it runs:

• Component placement and implementation: Because engineers will design your ICT hardware specifically for your PCBs, the hardware will connect with specific test points to link with specific components and assess their function. As they do this, they can also ensure that all components are in the right space and that your PCBs include all the right components. After these tests, you will know that all the right components are in the right spaces.
• Circuitry: As PCBs grow smaller, there is less space for circuits and components, causing engineers and manufacturers to create complex and tight units. Using ICT allows your teams to search for open or short circuits on each unit.
• Component condition: While testing that your unit has every component it needs in the right spaces, you will want to ensure that each component is of the highest quality. ICT can screen for damaged or low-functioning components, providing you with a way to control your component and unit quality.
• Electrical functionality: ICT provides a wide range of electrical functions, including resistance and capacitance. Your testing equipment will run specific currents through the components to see if they meet your determined standards.

Knowing how ICT works can help you determine if it is a good option for your PCBs. You can experience comprehensive quality and function testing with ICT because of the range of testing it offers.

Hardware and Software Used in the ICT Process

Like all testing equipment, ICT uses specific tools and equipment to function. Learning what hardware and software make up this testing process can help engineers and manufacturers better understand in-circuit testing techniques and what makes this testing method unique.

The Nodes

ICT hardware includes a set of test points that you can use to connect with various compartments, which many engineers and manufacturers describe as a bed of nails because of the density of contact points. Because they contact the PCB and its components individually, they are the hardware that measures the different requirements for each test.

To reach your PCB’s components in their unique configuration, engineers and manufacturers will need to arrange the nodes to meet the test points. This means that every PCB type will require a specific node arrangement so it can contact the components. If you manufacture and test multiple PCBs, you will need to invest in several in-circuit testers.

The Software

While hardware will carry out the testing, software will help direct the hardware and store vital information about your PCB and its components. It will prompt nodes to contact their component, begin running tests and collect data about their performance and placement.

Just as your nodes need customization before using them on your PCB, you will need someone to program your software to collect information specific to that unit. You use it to establish pass/fail parameters so it can determine whether components uphold standards.

Advantages of ICT

ICT is an incredibly precise testing technique that allows engineers and manufacturers to produce the same results every time. However, you can experience more benefits beyond quality and reliability with ICT, including:

• Time and cost efficiency: Compared to other PCB testing methods, ICT is very quick. It can finish testing all components within a few minutes or less. When you spend less time testing each PCB, your testing processes will cost less. ICT provides manufacturers and engineers with a quick and cheaper way of testing that still offers consistent and accurate results.
• Mass testing: Manufacturers can use ICT to test large amounts of PCBs because of its high efficiency. ICT provides comprehensive quality testing. While it only tests individual components, you can still understand how your unit functions. Manufacturers who produce higher PCBs can test units quickly without compromising quality.
• Customization and updates: Your hardware and software will include designs specific for each PCB, allowing it to optimize your testing. When you use ICT, you will know that every test and piece of equipment you use is designed for that product to provide the most specific testing. Further, you can update standards and test through your software.

Disadvantages of ICT

While ICT can be an excellent option for many companies, understanding the challenges accompanying it is vital when determining its suitability for you and your products. Some disadvantages of ICT include:

• Upfront costs and development time: Because you will need to program and customize your ICT hardware and software to fit each PCB configuration, prices and development time can be higher. You will have to wait for engineers to create nodes that contact every component in your unit and program the software with your product’s standards and specifications.
• Individual testing: While ICT can provide more comprehensive testing, it can only test how each component functions independently. You will need to use alternative testing techniques to understand how your components work together or overall unit functionality.