PCBA functional testing, Shenzhen China PCB maker
PCBA functional testing

What's the purpose of PCBA functional test?
The functional test for assembled circuit board is called FVT (Function Verification Test). The purpose of test is to pick up the poorly assembled board and test the whole function by simulating the circuit board.
This is to pick up the defective circuit board before assembling the machine, avoid occurring problem after whole machine assembled, also to avoid the waste of working labor and the loss of material.
 
PCBA testing includes five main types: ICT test, FCT test, Aging test, Fatigue test, and test in harsh environment.
1. ICT test mainly includes the open/short of the circuit, the voltage and current value and the fluctuation curve, the amplitude, the noise and so on.
2.  FCT test, need burn in IC program first, the function of the whole PCBA board is simulated and tested, the problems in hardware and software are found.
3. Fatigue test is mainly about sampling the PCBA board, performing high frequency and long time operation, observing whether there is failure, judging the probability of failure, so as to estimate the working performance of PCBA board in electronic products.
4. Test in harsh environment, testing the PCBA board exposed to high temperature, humidity, drop, splash and vibration, and the reliability of the whole PCBA batch is deduced.
5. The aging test is mainly to power the PCBA board or electronic products for a long time, maintain its work and observe if any failure occurs. After aging test, the electronic products can be sold in batch.
 
What does the functional test contain?
1. Power testing. Test power supply of PCBA, test individual point voltages using hysteresis comparator etc.
2. Open/short test for port/interface
3. IC module read and write functional test.
4. Special function testing (different PCBA testing requirements are different), for example, PCBA with infrared function, external receivers are required for testing.
 
ICT and FCT, this two testing methods are very different, not only because the ICT equipment and tools are relatively expensive, but it can give good test results and bring convenience to rework.
PCBA manufacturing process is complex. In the process of production and processing, there are maybe a variety of problems due to improper equipment or operation. Nobody can ensure that the products produced are qualified. Thus, it is necessary to carry out PCBA testing in order to ensure that each product does not exist quality problems.