The chassis is made of metal, and there is a screw hole in the middle, which connects to the ground. Here, a 1M ohm resistor is connected in parallel with a 0.1uF capacitor to the ground of the circuit board. What are the benefits of this setup? If the chassis ground is unstable or has … Read more
1. Characteristics and Repair of Capacitor Failures in Industrial Control Circuit Boards Failures caused by capacitor damage are the most common in electronic devices, especially with electrolytic capacitors being the most prevalent. Capacitor damage manifests as: Reduced capacity; Complete loss of capacity; Leakage; Short circuit. Since capacitors serve different functions in circuits, the characteristics of … Read more
Must-Read Books for Learning PLC (E-book Download Link) The inverter circuit board mainly includes the power board, control board, driver board, and panel. 1. Resistor Resistors are represented by the letter R on the circuit board, with units including: ohms (Ω), kilohms (KΩ), megohms (MΩ). Resistor symbols include: 1. Fixed resistors, adjustable resistors, special resistors … Read more
Source: ICisC Nanjing Integrated Circuit Industry Service Center 1. Choosing Pull-up Resistors for Microcontrollers As can be seen in the reset circuit, when resistor R1=10k, RST is high, but when R1=50, RST is low. It is clear that R1=10k is incorrect, as the microcontroller remains in the reset state and cannot function at all. The … Read more
PROFIBUS Physical Wiring and DP Connector Diagram From the diagram, it can be seen that when the switch is turned to “ON”, terminals A1 and B1 are connected to the termination resistor, so only A1 and B1 can be connected at the end of the DP network; otherwise, the termination resistor cannot be connected. When … Read more
Whenever a circuit board fails to operate normally, and the wiring checks out, it is very likely that an electronic component has failed. To repair it, you must identify the faulty component and replace it. However, locating the faulty component requires technical skills and certain techniques. Today, I will teach you how to use a … Read more
1. Introduction Originally, I needed to use the front end of the oscilloscope probe to create a shielded connection, but unexpectedly, when disassembling the front end, I discovered a strange part inside. It seems there is a small capacitor within this structure. 2. Internal Structure To minimize the impact on the circuit being measured, the … Read more
The termination resistor for the CAN bus is generally 120 ohms. In fact, during design, it consists of two 60 ohm resistors connected in series. There are typically two nodes of 120Ω on the bus, which is a well-known fact for anyone with a basic understanding of the CAN bus. However, as someone who struggles … Read more
In many circuits, small-value resistors are connected in series. Don’t underestimate them; they actually play a significant role. 1. SPI Signal Lines For SPI signals, the series resistor is generally around tens of ohms and has the following functions: 1) Impedance Matching. Since the impedance of the signal source is very low, and there is … Read more
Click the blue text to follow us In electronic engineering and maintenance, the identification and testing of electronic components are crucial steps to ensure the proper functioning of circuits and troubleshoot issues. Each component has its unique characteristics and functions; understanding their identification and testing methods helps engineers and technicians complete their tasks efficiently. 1. … Read more