The role of surface-mounted resistors in circuits

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Surface mount resistors are a relatively common type of component in electronic devices. Structurally, they can be divided into two main types: fixed capacitors and variable capacitors. It mainly converts electrical energy into thermal energy; it can also be considered an energy-consuming component, as heat is generated when electricity passes through it. Resistors typically serve to divide voltage and current in circuits; as for signals, both AC and DC signals can pass through resistors. Every resistor has a certain resistance value, which represents the degree to which that resistor opposes the flow of current. The unit of a surface-mount resistor is ohm, denoted by the symbol “Ω”. Ohm is defined as follows: when a voltage of 1 volt is applied across a resistor, if 1 ampere of current flows through this resistor, then the resistance value of this resistor is 1 ohm. Besides ohms, other units of resistance include kiloohms (KΩ), megaohms (MΩ), and so on. Together with other components, it forms various functional circuits, such as RC circuits. A resistor is a linear component. It is called a linear component because experiments have shown that, under certain conditions, the current flowing through a resistor is proportional to the voltage across the resistor – in other words, it obeys Ohm’s law: I=U/R. Common carbon film or metal film resistors can be modeled as linear resistors when the temperature remains constant and the voltage and current values stay within their rated limits. If the voltage or current value exceeds the specified limit, the resistor will fail to obey Ohm’s law due to overheating, and may even burn out. There are many types of surface-mount resistors, which are generally classified into carbon film resistors, metal resistors, wire-wound resistors, etc. They also include fixed resistors and variable resistors, as well as photoresistors, varistors, thermistors, and so on. But no matter what type of resistor it is, it has a basic symbol “R”.