Category of Resistors
There are various types of resistors if you combine function, shape, resistive material and its purposes.
Categorized by function, there are three types of resistors; fixed resistors, used in a electric circuit; trimmer potentiometer to adjust a circuit; variable resistor, used as a radio volume by changing the resistance.
Fixed resistors are divided into lead type(with lead wire) and surface mount type without lead wire. Surface mount type includes rectangular type and cylinder type. Resistors are more divided into resin mold type and ceramic type, etc depending on cealing material.
The materials of resistive body includes more; Film type that includes carbon film, metal film that applies Nicrom, metal oxide film and metal glaze composited by metal oxide and glass; metal plate, metal wire, those that apply metal foil; solid type that applies metal oxide ceramics.
The purposes of resistor are different depending on resistance tolerance, temperature characteristics, high voltage type, surge resistant type, fusing type and temperature characteristic that changes resistance. You have to select a suitable resistor for your purpose depending on combinations mentioned above.
Characteristics of fixed resistors
Fixed Chip Resistor
Resistors with the electrodes are processed for both soldering and bonding or either of them. These types of resistors do not have terminal wire(lead wire).
They are divided into rectangular type and cylindrical type. There are five following types according to resistive material.
Rectangular type——1. Metal glaze film type, 2. Metal film type, 3. Metal plate type
Cylindrical type——3. Carbon film type, 4. Metal film type
Among them, metal glaze film type consists mostly of the market considering cost, downsizing and mountability. Some statistics say that more than 90% of fixed chip resistors are metal glaze film type. The trend of downsizing is increasing amont this type of resistors; size 1005(1.0mm×0.5mm) or size 0603(0.6mm×0.3mm) are increasing, whereas mobiles telecommunication field like cell phoness and smartphoness are applying size 0402(0.4mm×0.2mm).
Rectangular type chip fixedresistors
This type is largely divided into thick film metal glaze type and thin film metal type. Thick film type is mostly massproduced. Thick film type is excellent for mountability and environmental resistance whereas thin film type features small resistance tolerance, small T.C.R. and low current noise. Especially for TC.R., thick film type is around 100×10-6/K while thin film type has extremely small T.C.R. like 10×10-6/K and achieves stable resistance. The size of rectangular type resistors are specified from 0402, 0603, 1005. 1608, 2012 and 3216. The size 0603 are rapidly increasing among mobiles telecommunication devices. Size 1005 and 1608 are applied mainly for consumer products, size 1608 and 2012 are widely used for consumer products, industrial equipment and automotive applications. High power type has size 3216, 3225, 5025 and 6331 in its portfolio.
Cylindrical chip fixed resistor
This is so called MELF type resistors which has such construction of general type axial lead resistors without lead wire but with metal plate cap on both ends of the body instead. The product features cylindrical shape with metal caps, so no two sides, excellent electrode strength and mechanical strength, excellent dimension tolerance and suppy and mountability. Metal film type also features to achieve resistance precision, T.C.R. and current noise in high level.
Two or more resistive elements are integrated and compound on a insulative substrate and this resistor circuit network is regarded as one electronic component. Each one can be connected as necessary. If this is integrated by resistors with two electrodes each, we call it alley, whereas we call network for those integrated by forming a circuit network.
The main applications are pull-up and pull-down resistors for digital circuits.
They are divided into SIP（Single Inline Package）type, DIP(Dual Inline Package)type, flat package type, chip carrier type.
In the past when the carbon film resistors were the mainstream, output of SIP type had been rapidly increasing to meat high density mounting. As the mounting technology changed into surface mount type, products shifted to chip network resistors and the current mainstream is chip network resistors and SOP(Small Outline Package) type.
Chip network resistors covers to response the high density mounting by chip resistors, which shows the largest growth in the output among network resistors. two-alley and four-alley are the mainstream of the demand, size 3216 is used for industrial equipment, size 1608 for electronic devices, size 1005 and 0603 for cell phoness, computers, DSC, digital video cameras.
Carbon film fixed resistors
Fixed resistors that have carbon film as a resistive element, which is the most popular type resistors from long ago. 1/4W type and 1/2W type are the most by electric category; now the small type like 1/4W type in size 3.2mm×φ1.9mm and 1/2W type in size 6.3mm×φ2.85mm are the mainstream and excellent in pulse resistance. They are widely used as general-purpose type.
Metal film fixed resistors
Fixed resistors that have metal film as a resistive element, which are high precision and stable, with small resistance tolerance, T.C.R. and aging. Low current noise, too. The main applications are industrial equipment like telecommunication, measuring equipment, or circuits for micro signals in computers, their peripherals, AV devices etc.
Metal oxide film fixed resistors
The resistive element is metal oxide film. The product is small (the smallest volume per rated power) size and has excellent heat resistant. Low T.C.R. is achievable by low cost compared to power type metal film resistors. Main application is power supply circuits.
Wirewound fixed resistors
The resistive element is metal resistive wire. Excellent pulse resistance and heat resistance. Small T.C.R. and low current noise. Difficult to get high resistance and not suitable for high frequency circuits because of its wirewound construction.
Those resistors are used as inruch current control resistors in power supply circuits. The products of low resistance are used for current sensing.