Turnkey pcb manufacturing, in-circuit test (ICT) equipment introduction

During turnkey pcb manufacturing, in-Circuit Test (ICT) is a standard test method for checking manufacturing defects and component defects by testing the electrical properties and electrical connections of online components. It mainly checks the on-line single component and the open and short circuit of each circuit network, and has the characteristics of simple operation, fast and rapid, and accurate fault location.

The probe bed type online test can perform analog device function and digital device logic function test, and the fault coverage rate is high during turnkey pcb manufacturing . However, a special needle bed clamp must be made for each single board, and the fixture production and program development cycle is long.

The flying probe online test basically only performs static testing. The advantage is that there is no need to make a fixture, and the program development time is short during turnkey pcb manufacturing.

1. The scope of ICT

On-line testing checks the electrical performance of the components on the board and the connection of the circuit network during turnkey pcb manufacturing. It can quantitatively measure devices such as resistors, capacitors, inductors, and crystal oscillators; and perform functional tests for diodes, transistors, optocouplers, transformers, relays, and operations amplifiers, power modules, etc. ; perform functional tests on small and medium-sized integrated circuits, such as all 74 series, Memory, common drivers, and switching ICs.

It finds defects and component defects by directly testing the electrical performance of online components during turnkey pcb manufacturing. The component class can check the component value for the tolerance, failure or damage; the memory class can check the program, etc.; technics class can be found such as solder short circuit, component wrong insertion, reverse plugging, missing, pin warpage, virtual welding, PCB short circuit, disconnection and other faults.

2, The characteristics of ICT

The faults of the test are directly located on specific components, component pins, and network points, and the fault location is accurate. No need for more expertise in the repair of faults during turnkey pcb manufacturing. It adopts program-controlled automatic test, which is easy to operate and quick to test. The test time of the board generally takes only a few seconds to several tens of seconds.

3. The meaning of ICT

On-line testing is usually the first test procedure in production, which can reflect the manufacturing status in a timely manner, which is conducive to the improvement of the technics during turnkey pcb manufacturing. The fault board tested by ICT is easy to maintain due to fault location and can greatly improve production efficiency and reduce maintenance costs. Because of its specific test items, it is one of the important testing methods for modern large-scale production quality assurance.