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Surface Mount Resistors

SMD Resistors Surface mount resistors, SMD resistors use surface mount technology, SMT to provide considerable advantages in terms of space saving and automated manufacture of printed circuit boards.

Surface mount resistors are electronic components used in a wide range of electronic circuits. They are designed to be mounted directly onto the surface of a printed circuit board (PCB), as opposed to through-hole resistors which are mounted by leads passing through holes in the board and soldered on the other side. Surface Mount Resistors, also known as SMT Resistors or SMD Resistors, are designed for use on printed circuit boards (PCBs). Unlike their through-hole counterparts, these resistors are mounted directly on the surface of the PCB, hence the name Surface Mount Resistors. They are a key component in surface mount technology, a method that allows for more efficient use of space on a circuit board and has revolutionized electronics manufacturing.

Characteristics and Construction:

  • Size: They are generally smaller than through-hole resistors, making them popular for applications where space on the PCB is limited.

  • Shape: Surface mount resistors come in various shapes, including rectangular, cylindrical, and chip-like designs.

  • Construction: Typically, they consist of a ceramic substrate with a resistive element (often made of metal such as nichrome or tantalum nitride) deposited on one surface. This resistive element is then coated with a protective layer to prevent damage.

  • Terminal Configuration: Surface mount resistors have terminations on either end that are soldered directly onto the PCB pads. This direct surface mounting makes them suitable for automated assembly processes.

Advantages:

  • Size: Their compact size allows for high component density on PCBs, crucial for miniaturization of electronics.

  • Improved Performance: Due to their smaller size, they have lower parasitic inductance and capacitance, which can improve high-frequency performance.

  • Automation: Surface mount technology (SMT), including resistors, enables efficient automated assembly processes, reducing manufacturing costs.

Types of Surface Mount Resistors:

  1. Thick Film Resistors: These are made by screen printing resistive paste onto a ceramic substrate and firing it at high temperatures. They are cost-effective and commonly used.

  2. Thin Film Resistors: These are made by depositing a thin resistive layer onto a ceramic substrate using methods like sputtering or chemical vapor deposition. They offer higher precision and stability but are usually more expensive.

  3. Chip Resistors: This is a common form factor for surface mount resistors, shaped like a small rectangular chip. They are available in a range of sizes and power ratings.

  4. Arrays: These are multiple resistors housed in a single package, providing space-saving and consistent matching for applications requiring multiple resistors.

Applications:

  • Surface mount resistors are used in virtually all types of electronic devices, including smartphones, computers, automotive electronics, medical devices, and more.

  • They are used for current limiting, voltage dividing, biasing transistors, terminating transmission lines, and various other applications where precise resistance values are needed.

  • Their small size and reliability make them particularly suited for portable and miniaturized electronics.

SMD Resistors (Surface Mount Resistors & Chip Resistors) are available at IBS Electronics from industry leading manufacturers. IBS Electronics is an authorized distributor for many smd resistor manufacturers including ASJ, ASC, IRC, Ohmite, Panasonic, Susumu, RCD, HTR, Welwyn, Yageo & many more. SMD Resistors are also known as Chip Resistors or Surface Mount Resistors. Please view our large selection of SMD resistors below.
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SMD resistor sizes

The size of SMD resistors is indicated by a numerical code, such as 0603. This code contains the width and height of the package. So in the example of 0603 Imperial code, this indicates a length of 0.060 and a width of 0.030.

Code Length (l) Width (w) Height (h) Power
Imperial Metric inch mm inch mm inch mm Watt
0201 0603 0.024 0.6 0.012 0.3 0.01 0.25 1/20 (0.05)
0402 1005 0.04 1.0 0.02 0.5 0.014 0.35 1/16 (0.062)
0603 1608 0.06 1.55 0.03 0.85 0.018 0.45 1/10 (0.10)
0805 2012 0.08 2.0 0.05 1.2 0.018 0.45 1/8 (0.125)
1206 3216 0.12 3.2 0.06 1.6 0.022 0.55 1/4 (0.25)
1210 3225 0.12 3.2 0.10 2.5 0.022 0.55 1/2 (0.50)
1218 3246 0.12 3.2 0.18 4.6 0.022 0.55 1
2010 5025 0.20 5.0 0.10 2.5 0.024 0.6 3/4 (0.75)
2512 6332 0.25 6.3 0.12 3.2 0.024 0.6 1

Solder pad land pattern

Code Pad length (a) Pad width (b) Gap (c)
Imperial Metric inch mm inch mm inch mm
0201 0603 0.012 0.3 0.012 0.3 0.012 0.3
0402 1005 0.024 0.6 0.020 0.5 0.020 0.5
0603 1608 0.035 0.9 0.024 0.6 0.035 0.9
0805 2012 0.051 1.3 0.028 0.7 0.047 1.2
1206 3216 0.063 1.6 0.035 0.9 0.079 2.0
1218 3246 0.19 4.8 0.035 0.9 0.079 2.0
2010 5025 0.11 2.8 0.059 0.9 0.15 3.8
2512 6332 0.14 3.5 0.063 1.6 0.15 3.8