Detailed explanation of voltage divider resistor and shunt resistor Working principle and application guide

In electronic circuit design, voltage divisionresistanceand shunt resistors are two common and important resistor configurations. They perform different functions in the circuit and are widely used in signal conditioning, voltage detection, current measurement and other scenarios. This article will comprehensively introduce the concepts, working principles and applications of voltage divider resistors and shunt resistors to help readers deeply understand the core points of these two resistor configurations.

A voltage dividing resistor refers to connecting two or more resistors in series to realize the voltage dividing function through the distribution of the voltage at both ends of the resistor. According to Ohm's law, the voltages across resistors with different resistance values ​​are also different, so the required voltage dividing ratio can be obtained. Voltage dividing resistors are widely used in voltage signal conditioning, analog acquisition and other fields.

A shunt resistor usually refers to a resistor connected in series in a circuit to measure current.Low value resistordevice. Because of its extremely small resistance, the voltage drop produced when current passes through is very small, but the current can be calculated by measuring the voltage drop. Shunt resistors are widely used in current sensing, power management and protection circuits.

When designing the voltage dividing resistor, you need to select the appropriate resistance value based on the input voltage and target output voltage. A resistance value that is too large may cause the circuit to respond slowly, and a resistance value that is too small may increase power consumption. In addition, the accuracy of the voltage dividing resistor directly affects the accuracy of the output voltage, so resistors with higher accuracy should be selected.

The resistance of the shunt resistor is usually very small, generally in the range of milliohms to several ohms. Power consumption and temperature rise issues need to be considered during design to ensure that the resistor can withstand the heat caused by the actual current. At the same time, low resistance can reduce the impact on the main circuit and improve measurement accuracy.

In analog signal acquisition systems, voltage divider resistors are often used to reduce high voltage signals to the acceptable range of the ADC. For example, the 12V voltage is reduced to 3.3V through a voltage divider resistor to facilitate sampling by the microcontroller. In addition, the voltage dividing resistor is also used to adjust the reference voltage to achieve flexible control of the circuit.

Shunt resistors are commonly found in power management modules and are used to monitor current in real time and protect circuits from overcurrent damage. For example, in battery management systems, shunt resistors can help monitor discharge current to ensure that the battery is operating within a safe range.

Although both involve resistors, voltage-divider resistors are primarily used for voltage division and shunt resistors are used for current sensing. The voltage divider resistor has a larger resistance and the shunt resistor has a smaller resistance. In addition, the voltage divider resistor focuses on the accuracy of the output voltage, and the shunt resistor emphasizes low voltage drop and high accuracy when measuring current.

When selecting voltage divider resistors and shunt resistors, the resistance value and power level should be reasonably selected based on specific application requirements. Pay attention to the temperature coefficient and long-term stability of the resistor to avoid measurement errors caused by environmental changes. At the same time, reasonable layout and welding process also have an important impact on resistance performance.

As basic components in electronic circuits, voltage divider resistors and shunt resistors play important roles in voltage regulation and current detection. Through reasonable design and selection, circuit performance and measurement accuracy can be effectively improved. Understanding their working principles and application scenarios can help engineers make more scientific decisions in circuit design and achieve efficient and stable electronic systems. In the future, with the continuous development of electronic technology, voltage divider resistors and shunt resistors will be more widely used, and their performance and accuracy will continue to improve.