In today’s era highly dependent on chips, the reliability of chips is directly related to the performance and stability of various electronic devices. For the BGA784 chip, conducting reliability screening burn – in tests is an important step to ensure its stable operation after leaving the factory. Now, let’s introduce in detail the relevant content of the reliability screening burn – in socket for the BGA784 chip.
1. Basic Information of the Tested Chip
The tested chip is a BGA – packaged chip with 784 pins. The pin pitch of the chip is 0.8mm, and the chip size is 23*23mm. This high – density pin configuration and specific size specification pose higher requirements for the test socket and burn – in test.
2. Chip Burn – in Test Process and Significance
Chip burn – in test is a process to accelerate the early failure of chips. By simulating various stress conditions that chips may encounter in actual use, potential defects inside the chips can be exposed in advance. The BGA784 chip will be connected to the burn – in environmental chamber through the test socket and burn – in board, and undergo HTOL (High Temperature Operating Life) burn – in test in the burn – in environmental chamber.
HTOL burn – in test is a common chip reliability test method. It can simulate the working state of chips in a long – term high – temperature environment, accelerate the physical and chemical changes inside the chips, and detect possible early failure problems of the chips. After the HTOL burn – in test is completed, the chips are subjected to performance testing to screen out the early – failing chips, ensuring that all the chips leaving the factory are in a reliable performance state. This process is like a strict “selection competition”, and only the chips that pass the test can enter the market and provide stable support for various electronic devices.
3. HTOL Burn – in Conditions
The HTOL burn – in conditions are a temperature of 125℃ and a single – cycle burn – in duration of 1000 hours. Under such high – temperature and long – term conditions, the materials inside the chip will undergo a series of changes, and some potential defects may gradually appear during this process. For example, the solder joints inside the chip may crack due to thermal stress, and the performance of transistors in the circuit may decline due to long – term high – temperature operation. By setting such burn – in conditions, the extreme situations that the chip may encounter in actual use can be effectively simulated, and the reliability of the chip can be improved.
4. Requirements for the Test Socket
The requirements for the test socket are very strict, mainly including the following aspects:
- Good Contact: The test socket needs to have good contact with the chip, with a contact yield of 99.8%. This means that in every 1000 tests, there may be only 2 cases of poor contact. Good contact is the basis for ensuring the accuracy and reliability of the test. If the contact is poor, it may lead to inaccurate test results and misjudgment of the chip’s performance.
- High – Temperature Resistance: It can withstand a high – temperature test environment of 125℃. During the HTOL burn – in test, the test socket needs to be in a high – temperature environment for a long time. If the test socket cannot withstand such high temperatures, it may deform or be damaged, affecting the progress of the test.
- Long Service Life: The service life is 5000 hours. This requires the test socket to have high durability and be able to maintain stable performance in multiple tests. If the service life of the test socket is too short, frequent replacement of the test socket will increase the test cost and time.
- Easy Maintenance: It is convenient for repair and maintenance. When the test socket fails, it can be quickly repaired and replaced, reducing the interruption time of the test and improving the test efficiency.
5. Our Solution
Our solution is a BGA784 flip – top structure plastic – shell probe – connected burn – in socket, which is a customized burn – in socket with the following characteristics:
- Size Adaptation: It is adapted to the chip size with a dimensional accuracy of ±0.02mm, ensuring a high chip contact yield. Precise size can ensure a tight fit between the test socket and the chip, improving the stability and reliability of the contact.
- Uniform Pressure: The flip – top has a knob structure to provide uniform pressure for the chip. Uniform pressure can ensure that each pin of the chip can have good contact with the test socket, avoiding poor contact problems caused by uneven pressure.
- Easy Replacement: The burn – in socket is locked to the PCB with screws through screw holes and limit posts. When the burn – in socket fails or reaches the end of its service life, it can be replaced separately, and the PCB can be recycled, saving the production quantity and cost of the PCB. This design not only reduces the use cost but also improves the maintainability of the test system.
- Cost Saving: The burn – in socket uses a plastic shell, which can ensure high – temperature resistance and save costs at the same time. Plastic materials have good insulation performance and high – temperature resistance, and the cost is relatively low, making them an ideal material for the test socket shell.
- Electrical Connection: The chip is connected to the PCB board through POGOPIN probes to achieve electrical connection. POGOPIN probes have good conductivity and elasticity, which can ensure a stable electrical connection between the chip and the PCB board. The software of the burn – in chamber can monitor the board and check the feedback of the chip to detect problems in the test process in time.
