The patch element has the advantages of small size, light weight, high installation density and strong shock resistance. Strong anti-interference ability, good high frequency characteristics and other advantages, widely used in computers, mobile phones, electronic dictionaries, medical electronic products, video recorders, electronic watt-hour meters and VCD machines. According to its shape, patch components can be divided into three categories: rectangle, cylinder and special-shaped [2]. There are resistors, capacitors, inductors, transistors and small integrated circuits. The nominal method of the patch component is different from that of the general component.

The following is mainly about the resistance nominal method of chip resistor:

The resistance values of sheet resistors are indicated on the resistance body as for regular resistors. There are three kinds of nominal resistance value, but the nominal method is not exactly the same as the general resistor.

Digital cable position nominal method

(General rectangular sheet resistance uses this nominal method)

Digital cable nominal method is to use three digits on the resistance body to indicate its resistance value. The first and second digits are significant digits, and the third digit represents the number of zeros added to the significant digit. There will be no letters in this one.

For example, "472" means "4700Ω"; "151" indicates "150Ω". If it's a decimal. "R" for "decimal point". It takes one significant digit, and the other two are significant digits.

For example, 2R4 indicates 2.4 ohms. R15 indicates 0.15Ω.

Color ring nominal method

(General cylindrical fixed resistor uses this nominal method)

Patch resistors, like general resistors, mostly use four (sometimes three) rings to indicate their resistance value. The first and second rings are significant numbers, and the third ring is the multiplier (the color ring code is shown in Table 1). For example, "brown, green and black" means "15Ω"; "Blue gray orange silver" indicates a "68kΩ" error of ±10%.

E96 numeric code mixed with letter nominal method

The digital code and letter mixed nominal method also uses three digits to indicate the resistance value, that is, "two digits plus one letter", in which two digits represent the E96 series resistance Schedule 2. Its third digit is the multiplier represented by a letter code (see Table 3). For example, 51D indicates 332×103. 332k "; "249Y" means "249 x 10-2; 2.49".