Printed Circuit Boards are considered as a complex assembly with hundreds of components and thousands of solder connections. Each component of the printed circuit board is expected to perform its role in the design in order to carry out the engineer’s vision. So, how would you test individual components on the board and its electronic characteristics for any imperfection? Here is where the significance of In-Circuit testing (ICT) lies in. In-circuit testing checks individual components on the board and its electronic characteristics for any imperfections. This is why ICT (in-circuit testing) has been a relied upon method of testing for electronics for years.
What is PCBA ICT Testing
ICT Testing is short for In-Circuit Testing, it is PCBA board testing method which helps detect defective components by using an electrical probe to check components at individual points. ICT checks for shorts, opens, resistance, capacitance, and other basic quantities which will flag any discrepancies. This fully automated test allows the techs to replace or fix any faulty parts before it goes to next procedure.
PCBA ICT Testing advantages and disadvantages
ICT Advantages
Easily detect manufacturing defects, ICT tests each component on a board, one at a time, can easily detects below defects.
- Component spacing, lead spacing, land sizes, and component sizes
- Component markings
- Soldering and process issues
- Shorts between traces and/or component leads
- Open circuits (“opens”) where electrical continuity should exist
- Values of resistors in the circuit
- Jumpers/switches in correct location/setting or not
- Presence/absence of passive components
- Presence/absence of active analog components
- Misoriented analog components
- Misoriented digital components
- Capacitance and inductance values
- Wrong or missing components
- Solder bridges
- Short circuits
Easy to Programme
An In-Circuit tester is very easy to programme – files can be taken from the PCB layout to generate much of the programme required.
Test results easy to interpret
ICT Test disadvantages
- Test fixtures are expensive.
- ICT sometimes fails to identify connector faults in high density, small package size SMT components.
- It shows inconsistent results if test pins do not make proper contact with the appropriate test pads.
- Its test pins need to be regularly cleaned and replaced to prevent failure.
Even with these flaws, ICT is still considered one of the best ways to test many PCBAs to this day.
PCBA testing not only helps manufactures to check the performance of each component but also enables them to complete the testing in less time. ICT, which have been in use for many years, still maintains its popularity owing to its ability to rapidly respond to dynamic product test requirements. The staff at Auspi has extensive knowledge in ICT as well as the other test methods. Feel free to reach out to our team for your next project and we’ll happily offer our advice.
