Quality Assurance


How do engineers ensure the quality of design is reflected in manufacturing? When making a high volume product with desired closer to 100 % yield rate, testing in different manufacturing stages is required to ensure final product received at each customers hand provides the best open box experience.


A good engineer needs to understand basic manufacturing processes and work with manufacturer early on to ensure design  come to fruition .

Basic Types of Testing

They are categorized as two types and stages.

In circuit test (ICT)

it is a board level test with fully assembled electronic components after surface mount reflow process where all components are soldered down. it is ICT test fixtures provides test coverage with incredible speed that is needed for a efficient factory (i.e improve unit per hour (UPH) throughput)

Benefits are coverage and speed

Cons: very costly and can't be reused for other products

Advanced test coverage

For embedded system, often one needs to verify the digital system, and mix-signal circuits. 

Note: This test is commonly seen in the factory test flow, where each board must be verified before inserted in it's mechanical housing.

Test fixture

A clamp shell device with embedded spring loaded pogo pins that comes into contact with test points on each board are used.

Flying probe test is a fixtureless machine that use use a robotic arm to move from test points to test points.

Functional circuit test (FCT)

It is a test that verify all subsystems are functioning correctly in a final assembled product.

benefits: functional verification after mechanical assembly to verify the final product are working as expected

Con: very manual.

System Image

Secure key provisioning

Screen panel  test

Speaker quality test

Microphone quality test

wireless connectivity test


Do we need to test every board?

Certain tests are done for everyone such as short and open test but components values test can be done in batches due to using the same rolls or material per each SMT pick and place machine cycle.

Summary & Conclusion

ICT and FCT are the basic fundamental into quality assure test for device manufacturing.  All those terms might be referred differently in different companies but the main idea is the same. One needs to ensure electronics are done correctly at PCB manufacture, surface mount process (Pick & Place, and Solder reflow), and final assembly stage.