Marking of SMD resistors

Marking of SMD resistors All surface-mount resistors are usually marked. It should be noted that chip resistors in 0402 case are not marked because of their size. Resistors with other sizes are marked in 2 ways. If SMD resistors have the resistance limit of 2%, 5% or 10%, their marking code consists of three digits: the first 2 represent the mantissa, and the 3rd - the degree for the decimal base. Thus we obtain the resistance value of the resistor in Ohms. For example, the resistor code is 106 - the first two digits 10 are the mantissa, 6 is the degree, finally we get 10x106, or 10 megaohms. Sometimes the digital marking of the resistors has the Latin letter R. It is like an additional multiplier, and is put to denote the decimal point. SMD resistors of the type size 0805 and more, with 1% accuracy, are denoted by a 4-digit code: the first 3 digits designate the mantissa, and the 4th - the degree for the decimal base. So we get the value of the resistor in Ohms. The given code can also have the letter R - the decimal point indication. For example, the resistor code is 3303 -- the first 3 digits of 330 are the mantissa, and the 4th is the degree, so eventually we get 330x103 that is 33kiloohms. The code marking of SMD resistors with the limit of 1% and the size of 0603 is indicated by two digits and a letter with the help of a special table. The digits show the code for which the value of the mantissa is selected from the table, and the letter is a multiplier with the decimal base, so we get the value of the resistor in Ohms. For example, the resistor code is 14R - the first 2 digits 14 are the code. In the table we get the mantissa value for the code 14, which is 137. R is the degree equal to 10-1. In the end we get 137x10-1 that is 13.7 Ohms. It should also be noted that the resistors with zero resistance, the so-called jumpers, are marked simply by the digit 0.