Explaining Why Pull-Up Resistors Are Added to I2C Signal Lines

Explaining Why Pull-Up Resistors Are Added to I2C Signal Lines

I2C is a two-wire serial communication bus, consisting of an SCL signal and an SDA signal. SCL is the clock signal sent from the master device, while SDA is the data signal, which is bidirectional, allowing devices to send and receive data through the SDA signal. When designing the I2C signal circuit, we add a … Read more

How to Select the Pull-Up Resistor Value for I2C?

How to Select the Pull-Up Resistor Value for I2C?

I2C is a common serial communication interface, which is available on most processors. The I2C interface is an open-drain structure, so pull-up resistors are needed in the design to drive the high level. As shown below: Rp is the pull-up resistor, and the dashed box contains the internal I2C controller structure of the chip (for … Read more

When to Use Pull-Up and Pull-Down Resistors for RS-485?

When to Use Pull-Up and Pull-Down Resistors for RS-485?

Follow+Star Public Number, don’t miss wonderful content Source | Zhou Ligong The RS-485 bus is widely used in communication, industrial automation, and other fields. In practical applications, it is often encountered whether to add pull-up and pull-down resistors and what size of resistors is appropriate. Below we will analyze these issues in detail. Why are … Read more

Detailed Explanation of RS-485 Pull-Up and Pull-Down Resistors Selection

Detailed Explanation of RS-485 Pull-Up and Pull-Down Resistors Selection

The RS-485 bus is widely used in communication, industrial automation, and other fields. In practical applications, we often encounter the question of whether to add pull-up and pull-down resistors and what size of resistors is appropriate. Below, we will conduct a detailed analysis of these issues. 1. Why Are Pull-Up and Pull-Down Resistors Needed? 1. … Read more

Don’t Get Trapped by IIC Bus!

Don't Get Trapped by IIC Bus!

1. Understanding I2C Communication Many friends often feel confused when developing the IIC communication protocol. On one hand, it’s normal to forget related knowledge if it hasn’t been used for a long time. However, it can be quite troublesome to keep looking at the communication timing diagrams, such as the starting level conditions, stopping level … Read more