Unstable chip burning? Try this

Date：2021-12-27 13:53:06Views：1262

Online burning, which integrates burning and testing, has attracted more and more attention. In order to speed up the burning efficiency, the burning tooling or fixture is often made, and the longer the wiring is required between the tooling, fixture and programmer. The longer the wiring is, the faster the signal attenuation is, and the burning defect rate also increases. This paper will introduce several measures to improve the instability of chip burning.

1、 Add shielding layer to prevent electromagnetic interference and electrostatic interference

As a tool to communicate closely with the chip, the programmer is sensitive to electromagnetic interference. The burning environment is generally factory workshop and high-power equipment, which makes the electromagnetic interference more serious. In order to reduce the electromagnetic interference, we can add a shielding net on the burning line, or choose the line with shielding function, such as shielding cable, network cable, etc. in addition, it is best to wear electrostatic gloves during operation to prevent electrostatic interference.

2、 Select wires with strong conductivity

The integrity of signal transmission is related to the material, length and thickness of the line. Thicker lines with stronger conductivity can be selected. Good materials can reduce internal resistance and signal loss, such as pure copper wire, gold-plated wire, silver-plated wire, etc.

3、 Reduce communication frequency

Communication frequency is an important parameter of information transmission. The higher the frequency, the faster the transmission speed. However, the attenuation of the signal will increase with the increase of frequency and weaken rapidly with the increase of transmission distance. Therefore, when the wiring is long, the communication frequency can be appropriately reduced to increase the stability of communication.

4、 Connect the pull-up or pull-down resistor on the key signal line

The programming interfaces of some chips have weak driving ability, so appropriate pull-up or pull-down resistors need to be added on the interface to enhance the driving ability. For example, IIC and swim interfaces need to be connected with strong pull-up resistors on the data line, and car key chips pcf79xx and ncf29xx need to be connected with pull-down resistors on the clock line.

5、 Select a programmer with strong driving ability

The driving ability of the programmer pin will directly affect the length of the wiring. Some online programmers on the market directly lead out the IO port of the internal control chip or the pin of the FPGA as the input and output of the programming signal. Their driving ability is weak. When the user's wiring is relatively long (generally greater than 30cm), the signal distortion will occur, resulting in unstable programming. When selecting the programmer, we need to choose professional online programmer, such as p800isp programmer of Zhiyuan electronics. Through multi-channel signal enhancement processing, we can increase the driving capacity of the programmer and solve a series of problems of long wiring.

The above is the related content of "chip burning instability" brought by the core detection. Through this article, I hope it can be helpful to you. If you like this article, you might as well continue to pay attention to our website, and we will bring more wonderful content later. If you have any needs related to the inspection and testing of electronic products, please call Chuangxin testing, and we will serve you wholeheartedly.