How to check the resistance value of a four-digit chip resistor

In electronic components,Chip resistorIt is widely used because of its small size and stable performance. For engineers and electronics enthusiasts, correctly identifying patchesresistanceThe resistance value is a basic and important skill. In particular, four-digit chip resistors are marked in a special way, and mastering their reading methods can effectively avoid selection errors. This article will introduce in detail how to understand the resistance value of a four-digit chip resistor to help you easily identify and apply it.

Chip resistors are usually identified by numerical codes, with three-digit and four-digit codes being common. Three-digit coding is more intuitive, with the first two digits representing significant digits and the last digit representing the multiplier. The four-digit code is mostly used for resistors with higher precision or larger resistance, and the coding method is slightly different.

Four-digit chip resistors generally use the first three digits to represent the significant digits, and the fourth digit to represent the multiplier. For example, the code "1001" means that the first three digits are "100" as significant digits, and the last "1" means multiplying by 10 to the power of 1, that is, 100×10=1000 ohms. The exponent of the multiplier is usually raised to the power of base 10.

The multiplier exponent of the fourth digit usually ranges from 0 to 9, representing 10 to the 0th power to 10 to the 9th power. For example, a multiplier of 0 means multiplying by 1, a multiplier of 3 means multiplying by 1,000, and a multiplier of 6 means multiplying by 1,000,000. Understanding this is key to correctly calculating resistance.

Sometimes the first three digits in the four-digit code may contain leading zeros, such as "0475", which means "047" is 47 significant digits, the multiplier "5" is multiplied by 10^5, and the resistance value is 47×100000=4.7MΩ. In addition, some manufacturers will use different coding standards, which need to be confirmed with the specific model instructions.

The resistance unit of four-digit chip resistors is generally ohms (Ω), but when the resistance value is large, it is also commonly expressed in kiloohms (kΩ) and megaohms (MΩ). Chip resistors usually also have tolerance marks, common ones are ±1%, ±5%, etc. Tolerance information needs to be understood through the color ring or packaging mark of the resistor.

Chip resistors of different sizes correspond to different power levels, such as 0603, 0805, 1206, etc. Although the size does not directly affect the resistance value, it is important to select a resistor with an appropriate power level in practical applications to avoid burning the resistor due to insufficient power.

When the resistance value of the chip resistor cannot be determined, you can use a digital multimeter to measure its actual resistance value. Pay attention to the power-off state when measuring to avoid other components in the circuit from affecting the measurement results.

The resistance reading of four-digit chip resistors mainly relies on the coding rule that the first three digits are used as significant digits and the fourth digit is used as the multiplier exponent. Mastering this rule can accurately determine the resistance value of chip resistors and avoid selection errors. Combining the size, tolerance and actual measurement methods of resistors can provide a more comprehensive understanding and application of chip resistors. I hope the content of this article can help you easily identify the resistance value of a four-digit chip resistor and improve the efficiency of electronic design and repair.