SMD resistor codes

How to read it

Yageo and Bourns use three digits for ±5% resistors in the E24 series and four for ±1% and tighter, where the value needs a third significant digit. So 472 is 4,700 Ω, 1002 is 10 kΩ and 3160 is 316 Ω. A three-digit code ending in 0 is not a round hundred: TT Electronics points out that 330 is 33 Ω, not 330 Ω. Below 10 Ω the letter R takes the place of the decimal point, as in 4R7 (4.7 Ω), 2R2 (2.2 Ω) or 34R8 (34.8 Ω). TT Electronics says the tolerance is not marked on its chips. Vishay’s marking table follows the same scheme: 1R0 to 9R1 for 1 Ω to 9.1 Ω, 103 to 913 for 10 kΩ to 91 kΩ, and 1002 to 9762 for 1% values from 10 kΩ.

Also searched as: 103 resistor, 4R7 resistor, chip resistor marking, EIA-96 code, R in resistor value, SMD resistor code, surface mount resistor code.

EIA-96 codes

On 1% chips of the 0603 size, Yageo, Bourns and TT Electronics print an EIA-96 code: two digits and a letter. The digits are an index to the 96 values of the E96 series, from 01 for 100 to 96 for 976, and the letter is the multiplier. Yageo and Bourns give Y for ×0.01, X for ×0.1, and A to F for ×1 up to ×100,000. So 01C is 100 × 100, 10 kΩ, and Yageo’s example 88A is 806 Ω. TT Electronics’ table also accepts S for Y, R for X and H for B; its example 07B is 1.15 kΩ.

The letter R

R means two things. In a three- or four-character code it is the decimal point (4R7 is 4.7 Ω), and in TT Electronics’ EIA-96 table it is another letter for X, ×0.1. An EIA-96 code is two digits then the letter; a decimal R sits between digits or in front of them.

The same values as color bands

103 is the chip marking of the resistor that is brown, black, orange in color bands, and 102 is 1 kΩ: Vishay’s table runs 102 to 912 for 1 kΩ to 9.1 kΩ and 103 to 913 for 10 kΩ to 91 kΩ. A single 0 on a chip is a zero-ohm jumper in Yageo’s marking specification.