There are two main types of aluminum shell resistors according to their colors. One is yellow, usually called gold resistors, and the other is aluminum, which is the most commonly used. The aluminum shell is processed by passivation and has a high-end appearance after anodizing.
What is the role of aluminum shell resistors?
1. Shunting and current limiting
When the aluminum shell resistor is connected in parallel with a device, it can effectively shunt current, thereby reducing the current on the device.
In practice, parallel circuits of aluminum housing resistors are often used to form a shunt circuit to distribute the current in the circuit.
2. Partial pressure
When the aluminum shell resistor is connected in series with a device, it can effectively divide the voltage and reduce the voltage on the device.
In practice, a series circuit of aluminum shell resistors can be used to divide the voltage to change the output voltage, such as the volume adjustment circuit of radios and amplifiers, the bias circuit of the semiconductor tube operating point, and the step-down circuit.
3. Impedance matching
The aluminum shell resistor can form an impedance matching attenuator, which is connected between two networks with different characteristic impedances, which can play a role in matching impedance.
4. Charge or discharge
The aluminum shell resistor also forms a charging or discharging circuit with some components to achieve the effect of charging or discharging.