Small steps. Big impact.


Fitbit QA


Hi Everyone,

We’re still on track here.

The main thing that we’re focused on now is developing testing systems to test each Fitbit as it goes through the assembly process. There’s several steps to the testing process.

The first is testing circuit boards. The Fitbit has 3 circuit boards. 2 are in the wearable Fitbit and 1 is in the wireless base station. After each circuit board is assembled, it is placed into a test fixture. One of our actual test fixtures is show below:


An operator places the circuit board into the fixture and then closes the lid on top of the board. The fixture contains many metal pins which make contact with special areas of the board. When the lid is closed, these pins make firm contact. Through these pins, we’re able to run tests which exercise various parts of the board automatically. Here’s a closeup of the board after the fixture lid has been closed on top of it. The black rubber feet gently push the board onto the test pins:

Closeup of the test fixture making contact with a board

Basically, we want to ensure that the right components have been placed on the board, that all the components are connected properly and that there are no manufacturing defects such as electrical shorts. We also do some mechanical tests such as automatically pushing the button to make sure that it’s connected properly. Here’s a solenoid switch that when commanded, pushes a button on the circuit board:

Solenoid switch to auto push buttons

2 of the boards are also connected by a cable, so we also do tests to make sure that the cable has been connected properly. Here’s an overhead shot of a test fixture that tests the cable connections. You can see the yellow cable drooping between 2 of the boards:

Testing the cable connections

Here’s some shots of the overall test fixtures:

Overall fixture

Fixtures in the lab

Once the circuit boards have passed testing, they are assembled in the Fitbit case or enclosure. Once enclosed we do another series of tests to ensure that

1. The enclosure process has not damaged the boards or the cable
2. The charging contacts and the USB cable have been properly soldered

We plug the Fitbit into its charger both ways to test proper charging contact connectivity and also connect the base station to a PC to make sure that the USB cable has been soldered properly and that the PC can communicate with the radio inside. We then do a series of special button presses on the Fitbit to put into a self-test mode, which does a final exercise of its functionality, including lighting up the display, checking components, etc.

In short, all this is to ensure that the Fitbits will be working well when they arrive on your doorstep.

FYI, 4 of our team are also flying to Singapore early Wednesday morning to start the assembly process. I’ll keep you posted on that.