top of page
Circuit Board_edited.jpg



A capacitor is a passive electronic component that is commonly used on printed circuit boards (PCBs). It is designed to store electric charge temporarily and release it when needed. A capacitor consists of two metal plates separated by a dielectric material. When voltage is applied across the plates, charge builds up on them, and an electric field is created between them.

Capacitors are used in PCBs for a variety of purposes, such as smoothing out power supply voltage, blocking DC current while allowing AC current to pass through, filtering out noise, and stabilizing oscillations. They come in a wide range of values, sizes, and types, including ceramic, electrolytic, tantalum, and film capacitors. The specific type and value of capacitor used on a PCB depends on the application and design requirements.



  • Energy Storage: Capacitors can store electrical energy and release it when needed. This is useful for applications that require a sudden burst of energy, such as in motor starting circuits or flash cameras.

  • Filtering: Capacitors can be used to filter out unwanted noise or signal components from a circuit. This is particularly useful in power supplies or audio circuits where unwanted noise can affect the quality of the output.

  • Decoupling: Capacitors can decouple a sensitive circuit from a noisy or fluctuating power supply. By placing a capacitor across the power supply rails, any noise or fluctuations are absorbed by the capacitor, ensuring that the sensitive circuit operates in a stable and consistent manner.

  • Timing: Capacitors can be used to create timing circuits or delay circuits, by controlling the rate at which the capacitor charges or discharges.

  • Size: Capacitors are available in a wide range of sizes and capacitance values, making them very versatile in PCB design. They can be used in both surface mount and through-hole components, allowing for flexibility in component placement and layout.

  • Cost: Capacitors are relatively inexpensive components, making them a cost-effective solution for a variety of applications.



Capacitors are typically manufactured in large quantities, and their values and ratings are standardized for compatibility and ease of use. However, it is possible to customize capacitors for specific PCB applications by altering their physical dimensions, dielectric material, and electrode material.



  • Power Supplies: Capacitors are often used in power supply circuits to smooth out voltage fluctuations and filter out unwanted noise. They can be used to stabilize the output voltage and reduce ripple, ensuring a stable and reliable power supply.

  • Timing Circuits: Capacitors can be used in timing circuits to control the frequency of oscillators or the duration of pulses. They can be used to create accurate and reliable timing signals in a wide range of applications, from simple timers to complex digital circuits.

  • Signal Coupling and Decoupling: Capacitors can be used to couple or decouple signals between different stages of a circuit. They can be used to block DC components, allowing only AC signals to pass through, or to filter out unwanted noise and interference.

  • Audio Amplifiers: Capacitors are commonly used in audio amplifier circuits to filter out unwanted noise and to block DC components from the output signal. They can also be used to create frequency-dependent filters to shape the tone or timbre of the audio signal.

  • Motor Control: Capacitors can be used in motor control circuits to provide a surge of power when starting up a motor, or to control the speed and direction of the motor. They can be used to smooth out the motor current and reduce electromagnetic interference.

  • RF Circuits: Capacitors are often used in RF circuits to tune the frequency response of antennas and filters. They can be used to create resonant circuits that match the frequency of the signal, improving the efficiency and sensitivity of the circuit.

Electronic Circuit Board

Procurement Process:

  1. Defining Capacitor Requirements: The first step is to define the requirements for the capacitors in your PCB design. This may include specifications such as capacitance value, voltage rating, temperature range, and size. It is important to select capacitors that meet the required performance specifications and are compatible with your PCB layout.

  2. Quotation: After identifying the requirement, we make a quotation for customers. This should include the quantity required, lead time, and any specific requirements for the capacitors.

  3. Production.

  4. Inspection: Once the capacitors have been manufactured, the next step is to receive and inspect them. This should include a visual inspection of the capacitors for any defects or damage, as well as testing them to ensure they meet the required specifications.

  5. Delivery and Storing Capacitors: Once the capacitors have been inspected, they should be delivered to customers and stored in a controlled environment that is free from moisture and other contaminants. This can help to ensure that the capacitors remain in good condition until they are used in the PCB assembly process.


Advantages of Ronghua:

  • Strong product supply capacity, all quantities are available here.

  • Reliable product quality, with ISO9001, ISO14001, CQC, IATF, UL approvals.

  • Customized products, workable for all brands such as TOSHIB, UTC, HOSONIC, TEAPO, BM, MURATA, TPSEMI, CHILISIN, LITEON, SEOUL SEMICONDUCTOR, MARCHING POWER, etc. 

  • Fast delivery, sample available, Ronghua provides one-stop services to meet different needs.

  • Favorable price, working with factories directly, Ronghua just provides factory prices.

  • Flexible response, solving problems quickly without delay, we know your concern and we can handle it flexibly.

  • Rich experience, complete management, and quality control system. 

  • Professional global trade team for your services from pre-sales to after-sales.

  • Grateful heart, all Ronghua people are working with a grateful heart, and making customers feel our gratitude.

bottom of page