Comparison Table of Resistance Code for Precision Chip Resistors

In the manufacturing process of electronic devices, precision SMT resistors are a common component. They have the advantages of small size, light weight, and easy installation, so they are widely used in various electronic devices. This article will provide you with a resistance code comparison table for precision SMT resistors to help you better understand and choose the appropriate resistor

1、 The resistance range of SMT resistors

The resistance range of precision SMT resistors is very wide, usually ranging from a few hundred ohms to tens of megaohms. The resistance values of these resistors can be precisely customized as needed to meet the performance requirements of various electronic devices

2、 Code representation of SMT resistors

In order to facilitate the identification and selection of patch resistors, the International Electrotechnical Commission (IEC) has developed a unified code representation. This code consists of four numbers, representing the resistance value, accuracy level, and temperature coefficient of the resistor. Specifically, as follows:

1 The first two digits represent the resistance value, measured in ohms (Ω). For example, 20 represents 20 ohms, and 330 represents 3300 ohms

2 The third digit represents the accuracy level and is divided into three levels: A, B, and C. A-level accuracy is the highest, while C-level accuracy is the lowest. For example, 2R104 represents an accuracy of 1% ± 0.5%, and 2R104J represents an accuracy of ± 0.1%

3 The fourth digit represents the temperature coefficient, which is divided into three levels: X, Y, and Z. The X series has the smallest temperature coefficient, while the Z series has the largest temperature coefficient. For example, 2R104J represents a resistance change of ± 4% at 25 ° C

3、 Code comparison table for precision SMT resistors

The following is a resistance code comparison table for precision SMT resistors for your reference:

|Resistance range (Ω) | Code representation | Accuracy level | Temperature coefficient|

|-------- | -------- | -------- | --------|

|Hundreds to thousands | X | A | X|

|Tens of thousands to hundreds of thousands | Y | B | Y|

|Hundreds of thousands to millions | Z | C | Z|

4、 How to choose the appropriate precision SMT resistor

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

1 Resistance value: Select an appropriate resistance range according to the requirements of the circuit design. If the specific resistance value cannot be determined, you can refer to the recommended range in the table for selection

Accuracy level: Select the corresponding accuracy level based on the circuit's requirements for accuracy. Generally speaking, the higher the accuracy requirement, the higher the price will correspondingly increase

Temperature coefficient: Select the appropriate temperature coefficient based on the working environment of the circuit. If the temperature difference in the working environment is large, it is recommended to choose a resistor with a smaller temperature coefficient. At the same time, factors such as the actual size of the resistor and pin spacing should be considered to ensure the feasibility of installation and welding

Mastering the resistance code comparison table and selection method for precision SMT resistors can help you more smoothly select and use resistance components in the electronic equipment manufacturing process. I hope this article can provide you with useful information and wish you a smooth work