0.25W 0.5% 10M OHM Metal Oxide Resistor Axial Leaded Wire Wound Variable Resistors

High Precision Axial Leaded Cylindrical Fixed Metal Film Resistor 1/8W 1/4W 1/2W

Description Of The Metal Film Resistor 1/8W 1/4W 1/2W

Metal film resistors are widely used resistors so far, with high precision, stable performance, simple and lightweight structure. It plays an important role in the electronic industry and military aerospace under high-precision requirements.

Metal film resistors are a kind of film resistors (Film Resistors). It uses high-temperature vacuum coating technology to closely attach nickel-chromium or similar alloys to the surface of the porcelain rod to form a film. After cutting and adjusting the resistance value to achieve the final required precision resistance value, it is then cut with appropriate joints and coated on the surface Sealed and protected by epoxy resin. Because it is a lead type resistor, it is convenient for manual installation and maintenance, and is used in most household appliances, communications, and instruments.

Advantages Of The Metal Film Resistor 1/8W 1/4W 1/2W 

* Low cost.
* Generates less noise than carbon composition resistor.
* Wide operating range.
* Long term stability.
* Low tolerance.
* Low temperature coefficient of resistance hence the resistance of the metal film resistors does not change easily with change in temperature.
* Very small in size.

APPLICATIONS Of The Metal Film Resistor 1/8W 1/4W 1/2W

• Industrial

• Telecommunication

• Medical equipment

• Automotive

Electrical Performances Of The Metal Film Resistor 1/8W 1/4W 1/2W

Power derating curve Of The Metal Film Resistor 1/8W 1/4W 1/2W

Resistor body color Of The Metal Film Resistor 1/8W 1/4W 1/2W

Size Of The Metal Film Resistor 1/8W 1/4W 1/2W (mm)

Factors to consider when choosing a resistor

Choosing a resistor should consider at least the following five factors: resistor type, rated power, rated voltage, temperature coefficient, and accuracy.

1, Resistor type
There are many types of resistors, including chip resistors, carbon film resistors, wire wound resistors, metal film resistors, metal oxide film resistors and so on. SMD resistors are small in size and suitable for large-scale integrated circuits. There are precision and common resistors. The circuits are very common; carbon film resistors have good stability, low negative temperature coefficient, good high-frequency characteristics, and are less affected by voltage and frequency, and noise electromotive force is relatively small. Small, wide resistance range, but not high precision; wire wound resistors have a low temperature coefficient, high resistance precision, good stability, heat resistance and corrosion resistance, mainly used as precision high-power resistors, but poor high-frequency performance; Metal film resistors have higher accuracy, better stability, and lower temperature coefficient than carbon film resistors; metal oxide film resistors are stable at high temperatures, resistant to thermal shocks, and have strong load capacity.
Each type of resistor has a certain operating frequency. When choosing a resistor, you can choose the type of resistor according to the frequency of the circuit. Especially in high-frequency circuits, you should choose a resistor with better high-frequency performance, and choose a higher Small dielectric loss resistance and package type size, etc.
2, Resistor rated power
The rated power of the resistor is determined by the hot spot temperature that the resistor bears, because the resistor is greatly affected by the ambient temperature. Therefore, in the circuit, it is necessary to consider the long-term working diameter temperature of the electronic product and the maximum temperature and the lowest temperature, so as to calculate how much resistance power is. Generally, the power used when designing the circuit is less than 1/2 of the rated power. Power. For example, if the actual power of the resistor reaches 0.4W, then a resistor with a rated power of 1W can be selected. This is to leave enough margin in the circuit for derating to improve circuit reliability.
3, resistance rated voltage
When the rated power of the resistor is constant, the rated working voltage increases with the increase of the resistor R, but with the increase of the voltage, the current density flowing through the resistor will also increase, resulting in serious local heating of the resistor, and the resistor is prone to aging and failure over time.
4, resistor temperature coefficient
Under the influence of the ambient temperature and the heat of the resistor itself, the resistance value of the resistor will drift, which is what we call temperature drift. The temperature coefficient of resistance mainly depends on the resistivity of the resistor material and the ambient temperature. General film resistor
The temperature coefficient of and wire-wound resistors is relatively small, while that of synthetic film resistors is relatively large. In circuits requiring relatively high resistance stability and circuits with very large environmental temperature differences, the influence of the temperature coefficient of resistance on the circuit must be fully considered.
5. Resistor accuracy
Resistance accuracy is also an important consideration for selecting hardware circuit resistance. Generally, it is not necessary to use high-precision resistors for circuits that are not strict in resistance. However, for instruments, current measurement circuits, voltage detection circuits, etc., the current or other Circuits that have a great impact on resistance fluctuations require precision resistors, and some circuits even use 0.01% high precision resistors.