resistance OPA2171AIDR It is a basic element in the circuit, which is used to limit the flow of current. The function of resistance is to consume electric energy by blocking the flow of current and convert electric energy into heat energy. In the circuit, the main functions of resistance are as follows:
1. Current limiting: Resistance can limit the current in a circuit by blocking the flow of current. According to Ohm's law, there is a linear relationship between resistance and current. The greater the resistance, the smaller the current.
2. Voltage regulation: the resistance can reduce the voltage by consuming electric energy. When the resistance is connected in series with the power supply, the resistance will consume a part of the voltage, making other components in the circuit obtain a lower voltage. This voltage regulation is very important in the circuit.
3. Voltage dividing function: In a circuit, multiple resistors in series can form a voltage dividing circuit. The voltage dividing circuit can divide the input voltage into different voltages and supply them to various components in the circuit. This is often used in circuit design, and the appropriate resistance value can be selected according to the needs.
4. Current limit: In some special cases, the current in the circuit needs to be limited to protect the safety of the circuit or components. For example, in the LED circuit, in order to prevent the LED from being damaged due to excessive current, an appropriate resistance will be connected in series to limit the current.
Why is it necessary to connect small resistance in series?
In the circuit, the series small resistance has the following application scenarios:
1. Current detection: small series resistance can be used to detect the current in the circuit. According to Ohm's law, there is a linear relationship between resistance and current. The smaller the resistance, the greater the current. Therefore, the current can be calculated by measuring the voltage at both ends of the resistance.
2. Voltage divider: small series resistors can be used in voltage divider circuit to divide input voltage into different voltages. A small resistance has a smaller resistance value, which can obtain a lower voltage division voltage, thus meeting the demand of some components in the circuit for a lower voltage.
3. Signal attenuation: In some signal processing circuits, in order to reduce the amplitude of the signal, it is necessary to connect the signal in series with an appropriate resistor. Because the resistance value of small resistance is small, the amplitude attenuation of signal can be more obvious.
In a word, the functions of small series resistance in the circuit mainly include current detection, voltage division and signal attenuation. By selecting appropriate resistance value, the requirements of circuit design and operation can be met.
