SMD Resistors Code

What are SMD Resistors?

A chip resistor is a surface mount electronic component commonly used in the manufacture and assembly of electronic equipment and circuit boards. It is made of thin film material and is directly attached to the surface of the circuit board, taking up less space and improving assembly efficiency.

Unlike traditional through-hole resistors, chip resistors can be attached to circuit boards automatically, which leads to higher production efficiency and lower cost. In addition, due to their small size and light weight, chip resistors can be more easily integrated into modern electronic devices to meet higher circuit density and smaller size requirements.

The basic structure of a chip resistor is a thin film composed of resistive material and conductive material, usually made into a rectangular shape, and has a pair of electrode connection terminals. They usually use thin metal or carbon films as the resistive material, and metals such as copper for the conductive material. The thickness of the film is usually between a few microns and tens of microns.

One of the advantages of chip resistors is their high precision, usually 1% or better. In addition, the stability of chip resistors is also very good, it can be kept within a certain range of resistance value, and it can also remain stable under the condition of temperature and humidity changes.

Another advantage is that they can handle high power. In some high power applications, the power of chip resistors can be as high as several watts. This makes chip resistors widely used in some applications that need to withstand high power and high voltage.

Chip resistors are usually available in many different values and sizes. Resistor values range from a few ohms to several megaohms, and sizes range from very small micro components to large resistors.

In conclusion, a chip resistor is a surface mount electronic component with high precision, high stability, high power and small size, which has become an indispensable component in the manufacture of modern electronic equipment and circuit boards.

SMD Resistor Code

The encoding method of chip resistors is usually different from that of resistor color code. The common encoding methods include digital encoding and letter encoding. It should be noted that the size of chip resistors is usually very small, so when choosing a resistor, not only the resistance value and accuracy need to be paid attention to, but also whether the size and power of the resistor meet the requirements.

Three Digit Code

The format of the three-digit coded chip resistor is XYZ, where X and Y represent significant figures, and Z represents the order of magnitude. The effective figure refers to the first two digits of the resistance value, the order of magnitude refers to the magnitude of the resistance value, and its value is expressed as 10 to the Z power.

Here are some examples in three-digit codes:

• 101: Indicates 100 ohms (Ω), where X=1, Y=0, Z=1.

• 222: Indicates 2.2 kiloohms (kΩ), where X=2, Y=2, Z=2.

• 473: Indicates 47 kiloohms (kΩ), where X=4, Y=7, Z=3.

It should be noted that the three-digit code is usually only suitable for chip resistors with relatively small resistance values, such as resistors in the range of 100Ω to 1MΩ.

Four Digit Code

The format of the four-digit coded chip resistor is WXYZ, where W, X and Y represent significant figures, and Z represents the order of magnitude. The effective figure refers to the first three digits of the resistance value, and the order of magnitude refers to the magnitude of the resistance value, and its value is expressed as 10 to the Z power.

Here are some examples in four-digit codes:

• 1001: Indicates 1 ohm (Ω), where W=1, X=0, Y=0, Z=1.

• 2210: Indicates 22.1 ohms (Ω), where W=2, X=2, Y=1, Z=0.

• 4751: Indicates 47.5 kiloohms (kΩ), where W=4, X=7, Y=5, Z=1.

It should be noted that the four-digit code is usually suitable for chip resistors with relatively large resistance values, such as resistors in the range of 1Ω to 10MΩ.

EIA-96

EIA-96, a coding system proposed by the Electronics Industry Association (EIA), aims to provide a convenient and reliable marking method for surface mount components.The EIA-96 marking system is based on the E96 series and therefore for resistors with a 1% tolerance

The EIA-96 encoding system is characterized by the use of a 96-character identifier symbol table. Among them, A to Z represent 26 letters, and numbers 0 to 9 represent 10 numbers. Each character represents a different resistance range (see table below).

Here are some examples in EIA-96:

• 02A ⇒ Code 02 = 102 with Multiplier A = 1 ⇒ 102 x 1 = 102 Ω ±1%

• 50C ⇒ Code 324 = 324 with Multiplier C = 100 ⇒ 324 x 100 = 32,400 Ω ±1%

• 93Z ⇒ Code 93 = 909 with Multiplier Z = 0.001 ⇒ 909 x 0.001 = 0.909 Ω ±1%

SMD Numbering Code Table based on E96 series

Code	Value	Code	Value	Code	Value	Code	Value	Code	Value	Code	Value
01	100	17	147	33	215	49	316	65	464	81	681
02	102	18	150	34	221	50	324	66	475	82	698
03	105	19	154	35	226	51	332	67	487	83	715
04	107	20	158	36	232	52	340	68	499	84	732
05	110	21	162	37	237	53	348	69	511	85	750
06	113	22	165	38	243	54	357	70	523	86	768
07	115	23	169	39	249	55	365	71	536	87	787
08	118	24	174	40	255	56	374	72	549	88	806
09	121	25	178	41	261	57	383	73	562	89	825
10	124	26	182	42	267	58	392	74	576	90	845
11	127	27	187	43	274	59	402	75	590	91	866
12	130	28	191	44	280	60	412	76	604	92	887
13	133	28	196	45	287	61	422	77	619	93	909
14	137	30	200	46	294	62	432	78	634	94	931
15	140	31	205	47	301	63	442	79	649	95	953
16	143	32	210	48	309	64	453	80	665	96	976

SMD Resistor Multiplication Factors

Code	Multiplication Factor
Z	0.001
Y | R	0.01
X | S	0.1
A	1
B | H	10
C	100
D	1000
E	10,000
F	100,000