Detailed explanation of the resistance expression of four-digit chip resistors

With the continuous development of electronic products,Chip resistorAs a basic component in electronic components, it is widely used in various circuit boards. patchresistanceThere are various methods of marking resistance values, among which the four-digit resistance value expression of chip resistors has attracted widespread attention due to its accuracy and application range. This article will comprehensively analyze the expression of the resistance value of the four-digit chip resistor to help readers deeply understand its coding rules and applications.

1. Basic concepts of four-digit chip resistors

Chip resistor, referred to as SMD resistor, refers to the resistive component in surface mount technology (Surface Mount Device). The resistance value is usually represented by a combination of numbers and letters for quick identification. Four-digit chip resistors use four numeric characters to indicate the resistance value, which is suitable for resistors with higher precision.

2. Structure of the four-digit chip resistor resistance expression

The four-digit chip resistor resistance expression consists of the first three digits and the last multiplier. The first three digits represent significant digits, and the last digit represents the power of 10 multiplied to. For example, the resistance value "1234" means 12.3×10^4 ohms, which is 123000 ohms.

3. Specific coding rules

The first three digits: represent the significant digits of the resistor and directly represent the first three digits of the resistance value.

The fourth digit: represents the multiplier, multiplied by 10 to the power of the number.

If the fourth digit is "0", it means multiplying by 10^0 to get 1; if it is "1", it means multiplying by 10^1 to get 10; and so on.

4. The actual multiplier corresponding to the multiplier number

| Multiplier Number | Actual Multiplier |

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

| 0 | 1 |

| 1 | 10 |

| 2 | 100 |

| 3 | 1,000 |

| 4 | 10,000 |

| 5 | 100,000 |

| 6 | 1,000,000|

5. Give an example of the resistance value of a four-digit chip resistor

Example: Number "4725"

The first three digits "472" represent 472

The fourth digit "5" means multiplying by 10^5

Therefore, the resistance value = 472×10^5 = 47,200,000 ohms, or 47.2MΩ.

6. The difference between four-digit resistance expression and three-digit expression

Three-digit chip resistors usually consist of two significant figures and one multiplier, and are suitable for resistors with a smaller resistance range. The four-digit chip resistor increases the number of effective digits and can express the resistance value more accurately, which is suitable for high-precision requirements.

7. Advantages of four-digit chip resistors in practical applications

High precision: one more significant figure, the resistance value is more accurate.

Easy to identify: standardized expression to facilitate automated identification.

Wide range of applications: suitable for precision instruments, communication equipment and other fields.

8. 注意事项及常见误区

识别时需注意数字顺序，避免混淆乘数位。

有些贴片电阻可能采用字母代替乘数，需要结合厂家手册确认。

阻值单位默认为欧姆，不同厂家标注可能略有差异。

四位贴片电阻阻值表达式通过前三位有效数字加一位乘数的方式，精确地表示电阻阻值，满足了高精度电子元件的需求。了解其编码规则和应用，有助于工程师和技术人员正确选型和使用贴片电阻，提升电子产品的性能和可靠性。在选购和使用过程中，应结合具体规格书，避免误读，确保电路设计的准确性。