Byelorussian customer placed a PCBA order from us, control board of a capacitive fuel level sensor that can be used for highly precise fuel measurement.

The customer placed the order in our company last year, who was very satisfied with the printed circuit boards we produced. This month they placed the third mass order with our company for this PCBA again.

Provided the PCB modification

In the previous order, we found that the components in two positions were not soldered well due to the design of the pads. The pad spacing of the pins on PCB is too large, and the contact area with the chip is less than one-fifth, whis has brought great difficulty to production. Our QA department found this problem and notified the whole team of this project. We recorded this problem and provided the PCB modification advise according to the customer's design. At last order, we repaired every soldering defect by adding tin and all the boards had passed the test after the repairing.

Checked the modification

Before this order's PCB production, we double checked the modification with the customer. They modified the positions of these two pads according to our suggestions. However, due to the pins of the two chips are very dense, the distance between the pads can not be too close, otherwise it will cause a short circuit.

After receiving the modified design from the customer, we made sample PCB to check with the chips. We confirmed the reasonable contact area between the pin and the pad, we began to mass production, after the production, we tested whether the PCB circuit is ok.

At the second place, the IQC department will check the quality of all the PCB and purchased components. In the meantime, our engineer check all the production files and write program for the auto assemble machine. When everything is ready, technicians put the components and PCB into the machine for assembly. More than 40 components on this PCBA, the progress of assembly is very smoothly. However, we payed more attention to the IC which the pads have been modified. After the assembly, we checked every component and confirmed they are all soldered well.

Install the program to every PCBAs

The next step, we need to install the program to every PCBAs. Customers provided dedicated equipment and programs for this project. Our professional technicians carred out this process to ensure that every circuit board’s program is correct and working.

Firstly, we need to connect two probes to the device for 12V power supply. The wire of other five probes connect to the ISP serial port. After all connections are made, open the “progisp” software on the computer. Then set the driver based on the chip.

Next, to select chip erase, programming FLASH, data automatically reload, verify FLASH, programming fuse. Setting the parameters of low potential, high potential and extended potential. At this point, all the setup is complete and the program installing is ready. Clicking “start” and wait for the progress bar to complete.

One piece of PCBA install program is finished . (see the test video at 86PCB )

Then, after the program has been installed in all the PCBAs, we test them with the program provided by our customer.

PCBA Test

It has many steps in the test:

1. Connect to PCBA via ISP and apply power to “+12VDC” and“ground” pins, power must be on all the time during programming and testing.

2. Set fuses.
3. Download firmware into flash memory.
4. Disconnect ISP and connect to PCBA.
5. Start the software.
If PCBA works , we will see the following information:

If PCBA does not work , we will see the error message as following:

If we receive the error message, our engineer will be responsible for investigating the cause of the error. He will recheck the PCB circuit, the soldeing condition, replaced the components and so on to find out the reason. Once find out the reason and repaired, we'll retest the PCB which are remindered error, and won’t ignore any details of the PCB boards. As professional PCBA manufacturer, we must ensure that all the PCBA our customer received is passed the test.

Last but not the least, we will package each PCBA carefully. First, we will wrap PCBA with shockproof film, then put them into the cartons. Before we seal the carton, we fill the space with filler. This step is to prevent the damage of components caused by fierce collision during long-distance transportation, finally seal the carton with tape.

This is the whole process of this project, it seems like complicated, but we're not deterred and successfully finished it. Our company has always emphasized professionalism, perfect and altruism. Our goal is not only to produce PCBA, but also to help our customers provide better products. We always treat every order with this attitude, so our customers trust our company very much.