PCBA Tech - Learn about smart manufacturing PCBA testing

PCBA testing service

PCB circuit board processing

PCBA test (English PCBA Test) refers to the electrical continuity of the PCBA circuit board mounted with electronic components and the detection based on input and output values. In the design of PCB circuit boards, there are numerical relationships between different test points, such as voltage and current. It is necessary to use professional test equipment or manual operation of a multimeter to test the test points to verify whether the actual PCBA board meets the design requirements. PCBA testing is a key step to ensure the quality of production and delivery. FCT test fixtures are made according to the test points, procedures, and test steps designed by the customer, and then the PCBA board is placed on the FCT test rack to complete the test.

PCBA test principle

Connect the test points on the PCBA board through the FCT test frame to form a complete path, connect the computer and the burner, and upload the MCU program. The MCU program will capture the user's input actions (such as long pressing the switch for 3 seconds), and control the on and off of the side circuit (such as LED flashing) or drive the motor to rotate through calculations. By observing the voltage and current values between the test points on the FCT test frame, and verifying whether these input and output actions are consistent with the design, the test of the entire PCBA board is completed.

PCBA test stand

Testing of large quantities of PCBA boards must be carried out, and a corresponding test frame (English Fixture) will generally be issued to assist in efficient completion. The principle of the test rack is to connect the test thimble to the test point of the PCB board. When the power is turned on, the key data such as voltage and current in the circuit are obtained and displayed on the display screen of the test rack to achieve the purpose of rapid detection. When the customer designs the PCB board, the engineer will consider its test plan, reserve PCB test points, and issue a professional test document or test plan to the manufacturer. Our company can make PCBA test frame by itself (equipped with engraving machine and test frame assembly engineer).

PCBA test cases PCBA test types are divided into the following types:

ICT (In-Circuit Test) test: It is mainly to test the voltage/current data of the test point after the PCB circuit board is energized, and does not involve the test of function keys or input and output.

FCT (Functional Test) test: It is necessary to first burn the prepared microcontroller (MCU) program into the program IC through a burner (such as ST-Link, JTAG) to realize the corresponding functional test. For example, after the button is pressed, the LED light is on; press two buttons at the same time to restore the factory settings and so on. Of course, whether the test of all functions can be carried out must be based on the premise that the PCB welding is OK and the PCB circuit is turned on, otherwise it cannot be realized.

Burn In Test: Perform long-term and periodic simulation of user input and output on PCBA boards that have been programmed and FCT passed to test their durability and welding reliability. Under special circumstances, it is also necessary to expose the PCBA board to a specific temperature and humidity environment.