Through hole resistors, also known as TH resistors or fixed carbon film resistors, are used to reduce the flow of electrical current within a circuit. As fixed resistors, they have predetermined values (voltage range compatibility), unlike variable resistors where the voltage range values can be adjusted.
Through hole resistors are constructed from metal film for general usage or carbon film for devices that require high tolerance. They have long, pliable leads that are inserted (either automatically or manually) into holes in printed circuit boards.
What Are Through Hole Resistors Used For?
Through hole resistors are widely used in various industries due to their versatility and ease of installation. They are particularly well-suited for larger circuit boards and prototyping projects where manual assembly or troubleshooting is common.
Industry Applications and Use Cases:
- Automotive: TH resistors are employed in various automotive systems, including engine control units, lighting systems, and audio equipment. They ensure proper voltage and current regulation for reliable operation.
- Telecommunications: These resistors are vital components in communication devices, such as routers, switches, and base stations, helping to maintain signal integrity and filter unwanted noise.
- Medical Equipment: Through hole resistors contribute to the functionality of medical devices like patient monitors, diagnostic tools, and imaging equipment. They ensure precise control and accurate measurements.
- Consumer Electronics: From televisions and audio systems to household appliances, through hole resistors play a role in controlling power distribution and filtering signals for reliable operation.
- Industrial Automation: In industrial settings, TH resistors are widely used in control panels, robotics, and machinery, offering robustness and ease of replacement in demanding environments.
How to Select the Right Through Hole Resistor
Consider the following factors when selecting a through hole resistor for your circuit or project needs:
- Resistance Value and Tolerance: Determine the required resistance value and tolerance based on your circuit's specific needs.
- Power Rating (Wattage): The through hole resistor wattage should be able to comfortably handle the expected power dissipation without overheating. Higher wattage ratings are necessary for applications with higher currents or voltages.
- Thermal Stability: Consider the operating temperature range of your application and select a resistor with suitable thermal stability. Carbon film resistors generally offer good thermal stability for most applications, while metal film resistors may be preferred for high-precision or high-temperature environments.
- Size and Package: Choose a resistor size and package that fits your circuit board layout and mounting requirements. TH resistors come in various sizes, from small 0201 packages to larger ones for higher power ratings.
- Application-Specific Requirements: Consider any special requirements for your application, such as high-frequency performance, high-voltage capability, or low noise.
Types of Through Hole Resistors
The most common types of through hole resistors are wire wound and axial components:
- Axial packages have flat profiles and cylindrical or box-shaped formats with leads on both ends. They are used for short distance applications.
- Wire wound resistors have metal wires wrapped around cores made from ceramic, plastic or fibreglass, which give them higher power ratings.
Advantages of Through Hole Resistors
Through hole resistors are especially advantageous for applications demanding durability and reliability. Their robust construction and secure soldering through the PCB create strong mechanical bonds, making them ideal for high-stress environments prone to vibrations or physical shocks.
- Superior Mechanical Strength: The leads pass through the board and are soldered on both sides, ensuring a sturdy connection.
- High-Temperature Resistance: Many through hole resistors can handle elevated temperatures, making them suitable for demanding applications.
- Ease of Replacement: When repairs are needed, TH resistors are relatively easy to desolder and replace compared to surface-mount components.
Comparing Through Hole Resistors and Surface Mount Resistors
Through hole resistors and surface mount resistors have their own strengths, making them suitable for different applications.
- Size: Through hole resistors are generally larger, while surface mount resistors are significantly smaller, enabling compact circuit designs.
- Assembly : TH resistors can be soldered manually or by machine, whereas surface mount resistors require automated pick-and-place machines for efficient assembly.
- Durability: The through hole construction offers greater mechanical strength, making them suitable for high-stress environments. Surface mount resistors, while smaller, may be more susceptible to damage from bending or impact.
- Performance: Both types perform well in most applications. However, surface mount resistors excel in high-frequency circuits due to their lower inductance and parasitic capacitance.
- Applications: Through hole resistors are often used in prototyping and applications requiring high durability. Surface mount resistors are favoured in mass production and high-density PCBs due to their small size and automated assembly compatibility.
Your Trusted Through Hole Resistors Supplier & Manufacturer
RS carries high-quality through hole resistors and carbon film resistors from leading brands like TE Connectivity, Vishay, Yageo, and more. To buy our TH resistors, simply visit our product page and filter according to your specific requirements. In addition, we also offer a range of passive components like electrolytic capacitors, barrier diodes and more. Need more information on delivery? Check out our Delivery page for details on services and fees.