As a most basic electronic component, resistors are widely used in various circuits. Generally, we also consider resistors to be the simplest type of electronic components. Except for power, there is not much attention. If I talk about this small resistor today, many senior electronic engineers may not really know how to use it. Do you believe it?
In the selection of resistors, if the special application of high-frequency circuits is avoided, generally we only consider the power of the resistors. For ordinary engineers, as long as the appropriate power can be selected by the current flowing through the resistor, it can be considered as qualified. If it can be considered Instantaneous power can be considered a good engineer. However, to really use resistors correctly, it is not enough to just do these two things. After reading the following text, you will understand that there are so many more special about using resistors.
The circuit form has the following advantages:
1. Multiple resistors are more conducive to heat dissipation. Two 1W 2 ohm resistors are used in parallel and one 2W 1 ohm resistor is used alone. The same current flows. Most of the time, two resistors are used in parallel. The temperature rise is small, and the resistance is at temperature. The power that can be sustained under high (such as higher than 70 degrees Celsius) conditions will be significantly reduced, so that a circuit with two resistors connected in parallel will perform better.
2. Multiple resistors can be combined to obtain a more ideal resistance value. For example, a 1.95 ohm resistor is more suitable than a 2 ohm resistor in actual applications. If you want to buy a 1.95 ohm resistor directly, there are certainly no two 3.9 ohm resistors. , Because 3.9 ohms is the standard resistance, and 1.95 ohms is not.