Hearing aid equipment main control product VQFN24-0.35 chip test socket
1. Requirements: In conjunction with the chip test socket of the customer's functional test board, the substrate parameters of the chip are in the QFN packaging form, 24pin, 0.35mm pitch. This packaging form is to make the size of the chip as small as possible, but at the same time it has the main control All functions including power management, audio processing and more.
2. Analysis:
1. Analyze the structure of the motherboard and determine whether the installation of the test socket is feasible? If it is not feasible, you need to consider other solutions to complete the conduction; currently this product is completed by the customer according to the test socket PCB design suggestions provided by us, and it is well compatible with our design;
2. Match the performance of the chip with corresponding high-performance probes. At the same time, the spacing and contact range of each pad need to be well controlled according to the pad design of the chip;
3. As a micro-pitch 0.35mm VQFN chip, the accuracy control requirements for the pitch of the processed holes are very strict, and special attention needs to be paid to a test after the processing is OK.
3. Product production and materials:
1. The analog design of the VQFN24-0.35 chip and the detailed display of each pad;
2. According to the specific pad size of the chip and the size of the corresponding probe pin type, make a comparison and match the control.
4. Difficulties
The main problem is its structure. Since the spacing is 0.35mm, its processing difficulty needs to be very high. The high requirements for processing accuracy make the design tolerance control extremely strict. It should be noted that: the center spacing between the pads conforms to The 0.35 spacing also requires attention to the tolerance range of the contact between the probe head and the pad; once this is completed, there is basically no difficulty. The low power consumption requirement does not require high frequency and other special requirements, and the design difficulty is not Not big.
