PCB News - Differences between FCT testing and ICT testing in PCBA testing

What is pcba test?PCBA testing is an important means to ensure the processing quality of circuit board PCBA.It typically includes two types of testing,FCT and ICT.The following will explain why FCT has become a trend to replace ICT in PCBA testing.

Why has FCT become a trend to replace ICT in PCBA testing?

FCT testing and ICT testing are two testing methods in PCBA functional testing,which have irreplaceable effects on the quality control of PCBA.Although both can test PCBA functional issues,their testing principles and testing items are different.

ICT testing refers to automatic online testing.It refers to the testing equipment produced by PCBA (Printed Circuit Board Assembly),which is a must for modern electronic enterprises. ICT has a wide range of applications,high measurement accuracy,and clear instructions for detected problems. Even workers with ordinary electronic skills can easily handle problematic PCBA.

ICT testing is mainly used to test whether there are abnormal conditions in the circuit functions of electronic components on the PCBA board, such as open circuits, short circuits, etc. When conducting ICT testing, it is necessary to arrange test points on the components in advance.During testing,the probe of the tester must also accurately align with the component test points. 

ICT testing is mainly static testing, that is, testing when there is no power.It can quickly detect the causes of abnormal component circuits,such as poor welding or component misinstallation,and provide abnormal test results to facilitate subsequent maintenance work.

ICT tester is a relatively simple simulation conducted by PCBA,mainly used to check component failures and welding failures. It is conducted in the next process of board welding, and problematic boards (such as reverse soldering of components,short circuit, and other issues) are directly repaired on the welding line.

FCT test (functional test) refers to a test method that provides a simulated running environment (excitation and load) for the test target board (UUT: Unit Under Test), making it work in various design states,thereby obtaining parameters from each state to verify the functionality of the UUT.Simply put,it is to apply appropriate excitation to the UUT and measure whether the output response meets the requirements.Generally,it refers to the functional testing of PCBA.

The FCT test is mainly used to test the electronic and electrical functionality of the PCBA board.The FCT test is a dynamic test, which requires testing when the PCBA board is powered on. The test principle is to simulate the actual operating state of the PCBA board, and to input signals or power supplies to the unit under test to test whether the data parameters of the unit under test are normal during various operations.The test mainly includes functional items such as voltage,current,and power.

FCT is an electronic and electrical functional test, that is, after completing the ict test step, turn to the product's power-on state to test the parameters of the product during normal operation. The advantage of this is not to take and place the product again.

In summary, it is not difficult to find the difference between Fct testing and ICT testing. Although both of them are used to test PCBA functional issues, ICT testing is mainly static testing, which mainly detects the circuit functions of various components on the PCBA board. FCT testing is dynamic testing, which is used to detect functional issues on the entire PCBA board. Generally, the order of the two testing methods is to conduct ICT testing first, After passing the test, conduct the FCT test. If the FCT test passes, it can only prove that the circuit board can work normally. Later, conduct aging tests and fatigue tests to test whether there are abnormalities in the stability and reliability of the circuit board. If all the tests pass, it can prove that the circuit board is qualified and can be used normally.

FCT vs ICT

Before delivering a PCBA board to a customer, it must undergo rigorous power and performance testing. In PCBA testing, FCT functional testing and ICT power component testing are the most common. When PCBA first emerged, ICT became mainstream, including many large electronic design companies. For example, the mobile phone industry is still using the ICT model. All original products have undergone rigorous testing so that we can quickly detect whether circuit board components meet design values and parameters., Avoid the tragedy of capacitor failure affecting the entire circuit board.

However, with the rapid development of the semiconductor industry, the density of electronic components is becoming increasingly high, and the production process and stability are becoming increasingly mature, which makes the application scope of ICT testing increasingly narrow.

Many small and medium-sized PCBA electronics manufacturers no longer take ICT testing as the mainstream mode, and gradually focus on FCT functional testing.The factory usually requires the customer to provide an FCT test plan, including test procedures, distribution of test racks, and related test steps, so that all PCBAs can pass strict FCT testing before shipment, and then be delivered to the customer.

Another reason why FCT replaces ICT is cost.FCT testing is relatively inexpensive.Customize according to the customer's design plan. The cost of a test stand ranges from 1000 to 5000. In addition, ICT needs to cover many components, which makes the manufacturing of the ejector pin platform extremely complex, difficult, and expensive. Therefore, ICT testing is now more common in general purpose equipment and product lines with large shipments.

More and more ICT device manufacturers are beginning to integrate FCT functionality into their devices. However, the functionality of FCT testing is difficult to standardize, making it more difficult to develop generic FCT testing equipment.Currently,the mainstream of the market is to customize according to different models and products of customers. Generally, according to the customer's FCT design plan, the corresponding test bench and test platform can be customized within 3 to 7 days,with a cost of between 3000 and 10000 yuan, which is more suitable for small and medium-sized PCBA processing companies.

FCT test

PCBA service process

1. Project consultation/quotation: The customer provides a complete quotation for PCBA data.

2. Customer orders: The customer confirms the quotation, signs the contract, and pays the advance payment.

3. Engineering evaluation: The data provided by the customer is evaluated through engineering and converted into final production data.

4. Raw material procurement: Purchase based on production data, arrange PCB manufacturing and component procurement,

5. PCBA production: SMT and DIP welding processing is performed after all plates are prepared.

6. PCBA testing: Conduct FCT testing or ICT testing on products based on customer needs.

7. Packaging and after-sales: The customer pays the balance, and PCBA packages and delivers the goods.