What is a resistor?: Regarding chip resistor sizes
Chip Resistor Specifications
Chip Resistor Sizes
The external dimensions of chip resistors are typically designated using company-specific notation and are indicated in both mm and inches.
|ROHM Part No.||Chip Size
(Length x Width)
|***004||0.4 mm × 0.2 mm||0402||01005|
|***006||0.6 mm × 0.3 mm||0603||0201|
|***01||1.0 mm × 0.5 mm||1005||0402|
|***03||1.6 mm × 0.8 mm||1608||0603|
|***10||2.0 mm × 1.2 mm||2012||0805|
|***18||3.2 mm × 1.6 mm||3216||1206|
|***25||3.2 mm × 2.5 mm||3225||1210|
|***50||5.0 mm × 2.5 mm||5025||2010|
|***100||6.4 mm × 3.2 mm||6432||2512|
***Represents part numbers (excluding chip networks)
What is 'Rated Power'?
The rated power is maximum power that can be used under continuous operation at a specified ambient temperature. When current is supplied to a chip resistor heat is generated. Since the upper limit of the operating temperature of a chip resistor has been determined, it is necessary to reduce the power in accordance with the derating curve for temperatures above Ta=70°C.
What is 'Temperature Coefficient of Resistance'?
In any material, the resistance of that material will change as the temperature changes. This extends to resistors as well. The rate of resistance change based on temperature is referred to as the Temperature Coefficient of Resistance. It is indicated in units of ppm/C and determined from the resistance change from the reference temperature and the change in temperature.