The relationship between size and power of SMT resistor quick identification table 0803/0601

In the manufacturing process of electronic devices, SMT resistors are a common component. However, do you feel confused about the shape of SMT resistors? Don't worry, this article will provide you with a quick identification table for SMD resistors, helping you easily identify SMD resistors of sizes 0803, 0601, and their corresponding power. The following is the main text of the article:

##1、 What is a SMT resistor

SMD resistors, also known as surface mount resistors, are electronic components that directly attach resistive components to the surface of printed circuit boards (PCBs). Compared to traditional fixed resistors, SMT resistors have the characteristics of small size, light weight, high reliability, and are therefore widely used in modern electronic products

##2、 Dimensions of SMT resistors

The size of SMT resistors is usually represented by two numbers, the former represents the diameter (in millimeters, mm), and the latter represents the thickness (in millimeters, mm). For example, 0805 represents a diameter of 8 millimeters and a thickness of 5 millimeters; And 221 represents a diameter of 2.2 millimeters and a thickness of 1 millimeter. Here are some common SMT resistor sizes and their corresponding power:

###1 Low power SMT resistor (P4W)

-0805: Approximately 1.2 Ω @ 4W

-1210: Approximately 2.2 Ω @ 4W

-169 Ω: approximately 1.5 Ω @ 4W

-221: Approximately 2.2 Ω @ 4W

-333 Ω: approximately 3.3 Ω @ 4W

###2. Medium power SMT resistor (P6W)

-0603: Approximately 1.2 Ω @ 6W

-1216: Approximately 3.3 Ω @ 6W

-168 Ω: approximately 2.2 Ω @ 6W

-222: Approximately 3.3 Ω @ 6W

-332 Ω: approximately 1.5 Ω @ 6W

###3. High power SMT resistor (P12W)

-0805: Approximately 4.7 Ω @ 12W

-1210: Approximately 9.5 Ω @ 12W

-169 Ω: approximately 7.9 Ω @ 12W

-251: Approximately 10k Ω @ 12W

-563 Ω: approximately 22k Ω @ 12W

##3、 How to choose a SMT resistor

When selecting SMT resistors, the following factors need to be considered:

1** Power demand * *: Select the appropriate power SMT resistor based on the actual power demand of the circuit. A small resistor cannot withstand large currents, while a large resistor may lead to problems such as high power consumption and severe heating

2** Precision requirements * *: For situations with high precision requirements, high precision SMT resistors can be selected; On the contrary, lower precision SMT resistors can be chosen

3** Temperature range: Different sizes of SMT resistors have different operating temperature ranges. When designing circuits, it is necessary to choose appropriate temperature coefficients and operating temperature ranges for SMT resistors based on the actual usage environment