In physics, resistance is used to represent the magnitude of a conductor's resistance to current flow. The greater the resistance of a conductor, the greater its hindrance to current flow. Different conductors generally have different resistance, which is a characteristic of the conductor itself. Resistive elements are energy consuming components that impede current flow.
The resistance value of a resistive element is generally related to temperature, material, length, and cross-sectional area. The physical quantity that measures the degree to which resistance is affected by temperature is the temperature coefficient, which is defined as the percentage change in resistance value for every 1 ℃ increase in temperature.
Resistors are the most commonly used component in all electronic circuits.
Resistance Unit
The resistance of a conductor is usually represented by the letter R, and the unit of resistance is ohm, abbreviated as ohm, with the symbol Ω. 1 Ω=1V/A. Larger units include kiloohms (k Ω) and megaohms (M Ω) (megaohms=one million, i.e. one million).
Resistors, abbreviated as resistors (usually represented by "R"), are the most commonly used components in all electronic circuits. The main physical characteristic of resistance is to convert electrical energy into thermal energy, which can also be said to be an energy consuming component. When current passes through it, internal energy is generated. Resistors usually play a role in voltage and current division in circuits. For signals, both AC and DC signals can pass through resistors.
K Ω (kiloohms), M Ω (megaohms), their conversion relationship is:
1T Ω=1000G Ω; 1G Ω=1000M Ω; 1M Ω=1000K Ω; 1K Ω=1000 Ω (i.e. one thousand input rate)
Market situation:
; At present, in the global market share, Taiwan, Japan, Chinese Mainland and South Korea rank first, and Europe and the United States almost no longer produce. Almost all major manufacturers have established production bases in China. Famous Taiwanese manufacturers such as EVERHOMS, VIKING, YAGEO, and BGOSTAR, while Japanese companies include KOA, Hokuriku, ROHM, and European and American company VISHAY. Brands commonly seen in the mainland market include EVEROHMS, VIKING, Yageo, and BGOSTAR.
Types of resistors:
Surface mount type: thick film surface mount resistor, thin film surface mount resistor, alloy surface mount resistor
Plug in class: Carbon film resistance, Metal film resistance, Metal oxide film resistance, Cement resistance, Wire wound resistance
Parameters of resistance:
Volume Specification Power Resistance Error Temperature Coefficient (TCR) Voltage Endurance (V)
The role of resistance:
The main function is to obstruct the flow of current, which is applied in current limiting, current diversion, voltage reduction, voltage division, load and capacitor matching, cooperative filters, and impedance matching. The functions in digital circuits include pull-up resistors and pull-down resistors.
Function of resistor:
Load resistance, sampling resistance, shunt resistance, protection resistance, etc.
