Principle of sound-light control delay switch circuit board: Acousto-optic control delay switch is mainly composed of sound control switch, light control switch and delay circuit. Voice control is to collect sound through the pole microphone, and generate pulse signal. The light-controlled circuit is controlled by photosensitive resistors. The resistance value of photosensitive resistors varies greatly [...]
The production process of circuit board is more complex, which involves a wide range of processes, from simple mechanical processing to complex mechanical processing, common chemical reaction, photochemistry, electrochemical thermochemistry and other processes, computer-aided design CAM and other knowledge. And in the process of production process problems and will always meet new problems and some [...]
As the PCB line production of fine line open circuit in the making problem become the important factor of affecting the product percent of pass, usually for line qualification rate of improvement action will consider the dry film adhesion, factors such as exposure energy, from the point of view of the whole system production, flatness [...]
Types of FPC reinforcement, we usually only use three types of reinforcement. PI polyimide, FR4 and steel sheet. 1. PI reinforcement: tolerance can be controlled in +/ -0.03mm, high precision, high temperature resistance (130-280 degrees Celsius) 2. Steel sheet reinforcement: manual assembly is required, the process is more complex and the cost will be higher. [...]
Testing whether the IC is burned out or short circuit requires professional knowledge. Generally, people without such knowledge and skills can make some simple judgments by carefully observing the appearance of IC: whether the IC surface has burned marks, such as blobs, cracks, discoloration and so on. IC pin break, unsolder. Does IC have burnt [...]
Let's look at the original purpose of JTAG, boundary testing JTAG controls (or HiJack) all IC pins. On the picture, maybe the JTAG will make all the CPU pins output... FPGA House published on 11-29 11:21•198 Reads Main features and application advantages of 2200 series PROGRAMMABLE DC power supply Whether in research LABS, design and [...]
Methods and skills in circuit board maintenance The introduction Control system due to the high price, so when its failure, in order to pay attention to economic benefits, cost saving, generally use the way of maintenance. But in the following cases, the need to replace a new circuit board: the circuit board has reached the [...]
Control system due to the high price, so when its failure, in order to pay attention to economic benefits, cost saving, generally use the way of maintenance. But in the following cases, the need to replace a new circuit board: the circuit board has reached the end of life; The circuit board is badly damaged [...]
FPC is also called flexible circuit board, flexible circuit board, soft board, soft circuit board and so on. The number of flexible circuit boards can be more than 100 lines, but the thickness can be 0.13mm, and the number of circuits of an FPC can be more than 100, but only occupy the thickness of [...]
The analysis report on the status quo of the printed circuit board (PCB) industry mainly analyzes the following points :1) The life cycle of the printed circuit board (PCB) industry. Research and judge the development stage of the printed circuit board (PCB) industry through the market growth rate, demand growth rate, product varieties, number of [...]