Immediately after the communication industry, the automotive electronics industry is the biggest consumer of PCBs. Starting with traditional mechanical products and moving on to the computer age through the gradual evolution of information technology, the automotive industry has seen a wide and intelligent integration of mechanical, electrical, and electronic high-technology products for automotive applications.
Whether it is the engine system, chassis, security, information, or the automotive environment systems, Rush PCB Inc. supplies automotive PCBs without exception. With the vehicle market on a definite upswing, there is significant development of automotive electronics, leading to an upsurge in the development of automotive PCBs.
Although automotive PCBs occupy an important position within the key PCB applications of the day, the special working environment inside the vehicle requires special considerations. Consequently, automotive PCBs must conform to safety requirements while carrying high currents. In fact, requirements for their reliability, environmental adaptability and other parameters are much higher than those for regular boards. At Rush PCB Inc., we have the technology and expertise to meet the above challenges of the automotive industry.
It is imperative that automotive PCBs are high in reliability and low in defects. We have accumulated adequate experience and technology to produce highly reliable products while consistently maintaining the future direction of our product development. We conform to the requirements of TS16949 in process control for achieving a low defects PPM.
Earlier, the concerns for reliability targeted primarily the devices mounted on the printed circuit boards. With the advancement of technology, both the components and the boards that mount them are becoming increasingly dense. Traces and spaces between them are shrinking, while the industry is predominantly converting to the HDI or high-density interconnect technology.
This has resulted in a growing demand for advanced monitoring techniques. For instance, at Rush PCB Inc., we have increased our inspection stages, and we have invested in collecting more parametric data, which we use with data analytic platforms. We are doing this in three stages:
- Increased inspection at the earlier stages, mainly the stencil printing stage
- Better Automated Optical Inspection or AOI methods
- Using parametric data for predicting abnormalities
We are sensitive to scrap costs, and therefore, we make sure all our products are reliable in the long term. For automotive boards and other mission-critical applications, we no longer allow end-of-line repairs. We understand that finding and isolating issues early in the process is critical for reducing scrap. To achieve this, we collect data during assembly and correlate it to test data.
This way, we achieve a more granular view of our products. Not only does this have a huge impact on their reliability, but we can also use this data to identify and isolate issues much earlier in our manufacturing process.
To reduce the automotive PCB defect rates during production, Rush PCB Inc. follows several special practices. We have boosted our investments in inspection, testing, and analytics for meeting demands for reliability. Automotive sector is highly safety-critical and the reliability demands are very stringent. Some steps we take to reduce the PCB defects are as below:
PPM Quality System
At Rush PCB Inc., we use parts per million or PPM for measuring the defect rate in our PCB manufacturing processes. We have trained people responsible for the quality of PCBs using statistical analysis. The statistical analysis method analyzes each piece of defective board through tools such as micro-slicing, categorizing the defect and assigning it to a specific process in the production chain.
We compare test results from two different batches of PCBs and track the PPM readings from the corresponding batches. This helps us to understand the performance of two test machines. We select the better performing machine for testing automotive PCBs.
We often use a second test method to augment initial testing for critical tests like high-voltage electrical breakdown test to improve the defect rate of automotive PCBs.
Fool Proof Sorting System
One of the main reasons for increased failure is human error while testing and sorting. We ensure a fool-proof sorting system by using two covered boxes electrically linked to the test machine. The good-boards box opens only when the test machine produces a go result, while the defective-boards box opens only when the test machine produces a no-go result. This ensures the operator cannot mistakenly place a defective board in the good-boards box and vice-versa.
Improved Test Parameters
We set higher test settings for detecting more defects. For instance, when the high voltage threshold is set slightly high, we inherently increase the number of high-voltage leakage defects, thereby improving the detection rate.
Check Test Machine Parameters
Test machines usually run for long periods, and this may cause their settings to drift. We regularly keep a check on the parameters of our test machines to ensure they we adjust and set them properly for producing accurate test results. We regularly maintain our machines and adjust their internal parameters for top performance.
Military & Aerospace PCB Assembly
Rush PCB Inc. aims for zero defect in all automobile PCBs. For this we ensure we are maintaining our process equipment, raw materials input quality, and our test instruments to the best possible performance standards. This way we keep our defect PPM rate at the lowest possible for all our products.