Is the chip resistor more expensive than the larger the resistance?

Of course not, generally speaking, the more powerful the chip resistor, the more expensive, the more accurate the grid, the more aerospace-grade "military supplies" civilian supplies.

For example, in the case of high power, high precision, aerospace-grade chip resistance, it may be very high, and hundreds of pieces of resistance are also normal.

Generally speaking, the resistance applied in integrated circuits is too small and too large to be limited by the process and is relatively difficult to obtain, so the chip resistance that is too large (more than 1m precision resistance) or too small (below 10R) is relatively expensive, of course, the same as the resistance value resistance and LS said, the specific ** is in the range of RMB. You check it out.

It is mainly related to the volume, accuracy, and whether it is commonly used, and generally the same size of chip resistor, if the accuracy is the same, ** is the same. The higher the accuracy, the higher the **.

There are two ways to read the resistance value of the chip resistance, 1. Digital method (printed on the resistor, very small words): for example, 103, that is, 10 * 10 3 = 10k, 101 = 100 euro.

There is also a genus, which has r, which represents the decimal point, such as 3r3=ohan and r33=ohne. This is generally suitable for 5% resistance.

2. The ** table of the E96 sequence (that is, the resistance with an accuracy of 1%), to check the table, there is a special **, such as 39x, by looking up the table, 39 represents 249, x represents the -1 power of 10, that is, Europe.

The size of the patch is related to its own power, and if you need a lot of power, it is better to use in-line cement.

I don't know what exactly you mean by model.

The main parameters of chip resistors include resistance, power, accuracy and size The general size is 1005 1608 2012 3216

Larger than 2512 is 3216, and no matter how large the resistor is, it is generally not SMD.

In addition to the resistance value, do you have any requirements for accuracy?

Sampling resistor, also known as current detection resistor, sampling resistor refers to current sampling and voltage sampling, and the current sampling series resistance value is small, its function is to accurately collect the current in the circuit, voltage sampling parallel resistance value of the resistor. This type of resistor is named according to the use and function of the product, so engineers call it a sampling resistor.

Sampling resistor effect.

The sampling resistance function is used as a reference, commonly used in the feedback circuit, taking the regulated power supply circuit as an example, in order to keep the output voltage constant, a part of the voltage should be taken from the output voltage as a reference (commonly used in the form of sampling resistance), if the output is high, the input terminal will automatically reduce the voltage to reduce the output; If the output is low, the input will automatically increase the voltage to increase the output. It is generally used in power supply products, or the power supply part of electronic, digital, and electromechanical products, and is powerful. Sampling resistors are commonly seen on many electronic products.

Characteristics of the sampling resistor.

Sampling resistance is generally divided into plug-in resistance, chip resistance, sampling resistance, low resistance value, high accuracy according to the requirements of the specific substrate, the general resistance value accuracy is within 1%, and the higher requirements of the use of precision resistor. Most of the plug-in resistors produced in domestic factories are made of constantan and manganese copper. However, most users need the high-precision resistors of the chip to achieve the sampling function to meet the automation requirements of small product production.

It is rare for a manufacturer to produce resistors with low temperature coefficients, high accuracy, and ultra-low resistance values to meet user requirements.

Generally, the sampling resistance value is less than 1 ohm, which belongs to the milliohm induction resistance, but some resistances, sampling voltages, etc., must choose a large resistance value resistor, but this kind of resistance base is large and the error is large. In this case, it is necessary to select a high-precision non-inductive resistor (which can achieve an accuracy of 1/10,000) to make the sampling data very reliable. Ultra-low resistance value resistors (ohms, 2 mOhms, 3 mOhms, 10 mOhms, etc.), SMD alloy resistors, high-power resistors (20W, 30W, 35W, 50W, 100W) and other products with a temperature coefficient of plus or minus 5ppm.

The alloy chip resistor adopts a special alloy that conforms to the high-power electrical characteristics, high purity, high thermal conductivity, low-temperature drift and high temperature resistance, and the one-piece non-cutting structure greatly reduces the heat dissipation problem on the circuit board, and can achieve almost no inductance value.

As a current carrier, the alloy resistor has accurate resistance, temperature stability, product safety, and stability is significantly higher than that of ordinary ceramic alloy resistors. At the same time, the thermal conductivity of metal is also its great advantage. Especially in the application of power supplies and other related products, when instantaneous impulse current, short-circuit current or pulse current is generated, the alloy is the first choice as a current medium to detect the current.

0805 package size 0402 package size 0603 package size 1206 package size.

Relationship between package size and power:

0201 1/20w

0402 1/16w

0603 1/10w

0805 1/8w

1206 1/4w

The correspondence between the package size and the package.

SMD resistors. The power refers to the electrical resistance due to the Joule heat when passing current.

The power generated. According to Joule's law.

Calculate: p=i2 r.

Rated power. : Refers to the maximum allowable power at a certain temperature, usually the rated power at an ambient temperature of 70°C.

Rated voltage. : The rated voltage can be calculated according to the following formula.

Rated voltage (V) =

Rated power (W) Nominal resistance ( ).

Maximum Operating Voltage: The maximum voltage that can be applied to both ends of the chip resistor.

The relationship between the package, power and voltage of the chip resistor is as follows:

The 0603 resistor power is 1 10W. According to the size of the chip resistor, there are 9 package sizes, and its rated power is different for different package sizes. The package size of the chip capacitor is the same as the chip resistor.

Power measurement is used to measure the power consumed by electrical equipment, and is widely used in research and development and production lines for household appliances, lighting equipment, industrial equipment, etc.

Advantages of SMD componentsSMD components have the advantages of small size, light weight, high installation density, strong shock resistance, strong anti-interference ability, good high-frequency characteristics, etc., and are widely used in computers, mobile phones, electronic dictionaries, medical electronic products, camcorders, electronic watt-hour meters and VCD machines. SMD components can be divided into three categories according to their shape: rectangular, cylindrical and special-shaped.

There are resistors, capacitors, inductors, transistors, and small integrated circuits. The nominal method of SMD components is different from that of general components.

Thank you for your guidance and wish you a happy family life and a safe life.

The unit of chip resistance is ohms, if it is a chip resistance with an error of 5%, the third bit is the number representing 0 or the n in the power of 10, and the first place is representing the significant number, if the chip resistor is printed with 473, it represents 47000 ohms, that is, 47k, if it is printed with 510, it represents 51 * 10 to the power of 0, that is, 51 ohms, and must not be considered to be 510 ohms, because 511 represents 510 ohms. If there is a resistance to the decimal point, then the decimal point is represented by "r", e.g. 5r6 represents ohms.

However, some precision resistors with an error of plus or minus 1% are represented by 4 digits, such as 1201, which represents 1200 ohms, with an error of plus or minus 1%. There are also precision resistors printed on the number does not represent the resistance value, can only be measured with a bridge or multimeter to know the resistance value.

SMD resistor: one of the metal glass glaze resistors.

Guanfa chip resistor, also known as chip fixed resistor, is a resistor made by mixing metal powder and glass uranium powder and printing it on a substrate by screen printing. There are many subdivisions of chip resistors, which are commonly divided into conventional thin film chip resistors and high-precision and high-stability chip resistors.

01a：100ω

01b：1000ω

01c：10000ω

01d：100000ω

01 represents 100, and a, b, c, and d are to the power of 0, 1, 2, and 3 of 10 respectively. So 01b=100 10=100

This method is called the e96 numeric ** mixed letter nominal method.

The numeric ** and alphabetic mixed nominal method also uses three digits to indicate the resistance value, that is, "two digits plus one letter", where the two digits represent the E96 series resistors Schedule 2. Its third digit is the magnification indicated by the letter **. For example:

51d" means "332 10 3;332kω”；249y" means "249 10 -2;"。