![<?echo $_SERVER['SERVER_NAME'];?>](/template/twentyseventeen/skin/images/header.jpg)
Weekend times are always so easy
Don't talk about technology with your friends today
Let us work together to create a gift for a dedicated engineer
= Preliminary preparation: This power supply is required to provide four voltage levels according to the requirements, wherein: +5V, -5V, +36V is one way; +12V is the other way. Among them, +5V is mainly used for the SCM used in the following lines, and the current is 1A; -5V is used by some op amp ICs that require dual voltage supply, and the current is 0.5A; +36V is used by subsequent devices for a certain detection function, and the current is only 0.1A. . The other way +12V is to provide power for the DC12V relay used in the follow-up line, the current is 0.5A
= Start to focus
First, according to the actual situation of the user, it is finally determined that the AC90-265V power supply environment can meet the actual needs. At the beginning, I intended to use the UC38 series IC as a design blueprint for a simple replacement design. I could consider other factors such as cost factors and technical support, and I gave up the idea. In the end, I personally decided to design the IC based on A6252, a popular IC that was more than a decade ago. A6252 is a product of Japan Sanken Electronics Co., Ltd. It was widely used in CRT TVs and other household appliances.
Figure 1 is my hand-painted schematic diagram of the power supply line, due to cost constraints on my post-stage -5V, +12V using three-terminal integrated voltage regulator IC regulator; taking into account the actual situation of +36V, I use three-terminal adjustable stability Pressure tube LM317L (current 0.5A) for voltage regulation and other aspects of processing. Because of the quality of +5V power supply, it largely determines the stability of the follow-up line work, so I use TL431 and PC817 this "golden partner" to implement "VIP" level processing.
The two figures above show the finished circuit board. The output and input follow the principle of left-low-right-high. From the chart, it should be easy to see that I have done my best to limit EMI, overvoltage, overcurrent protection, and other requirements related to power supply hardware requirements at a limited cost.
This close-up is the "male one" of the power supply, the A6252. This is a four-pin package and is available in 8-pin packages in some products.
The last display is the PCB on the back of the power supply. Please pay attention to the partitions opened in the board. As for the reason, I think I would like to listen to the opinions of the altarists. The white line is framed by the low pressure section, which is easy to distinguish between high and low pressures. It can also serve as a reminder for maintenance.
The 7-inch tablet can be used as the golden size of a tablet computer. It is small and portable. It can be used at home and outdoors. You can browse the web, watch videos and play games. It is a household artifact. Although the size of the 7-inch tablet is inclined to the tablet, the function is more inclined to the mobile phone, so it can also be used as a substitute for the mobile phone. Compared with other sized tablets, the 7-inch tablet has obvious advantages in appearance and weight. Both the body size and the body weight have reached a very reasonable amount.
1.In appearance, the 7 inch tablet computer looks like a large-screen mobile phone, or more like a separate LCD screen.
2.In terms of hardware configuration, the 7 inch tablet computer has all the hardware devices of a traditional computer, and has its own unique operating system, compatible with a variety of applications, and has a complete set of computer functions.
3.The 7 inch tablet computer is a miniaturized computer. Compared with traditional desktop computers, tablet computers are mobile and flexible. Compared with Laptops, tablets are smaller and more portable
4.The 7 inch tablet is a digital notebook with digital ink function. In daily use, you can use the tablet computer like an ordinary notebook, take notes anytime and anywhere, and leave your own notes in electronic texts and documents.
7 Inches Tablet Pc,Quad Core Tablet 7 Inch,7 Inch Gaming Tablet,Supersonic Tablet 7 Inch
Jingjiang Gisen Technology Co.,Ltd , https://www.jsgisengroup.com