{"id":3206,"date":"2026-08-30T19:24:29","date_gmt":"2026-08-30T11:24:29","guid":{"rendered":"http:\/\/www.privilege55.com\/blog\/?p=3206"},"modified":"2026-08-30T19:24:29","modified_gmt":"2026-08-30T11:24:29","slug":"what-are-the-charging-circuits-used-in-pcb-power-supplies-for-batteries-46f3-dbb687","status":"publish","type":"post","link":"http:\/\/www.privilege55.com\/blog\/2026\/08\/30\/what-are-the-charging-circuits-used-in-pcb-power-supplies-for-batteries-46f3-dbb687\/","title":{"rendered":"What are the charging circuits used in PCB power supplies for batteries?"},"content":{"rendered":"

As a seasoned supplier of PCB power supplies, I’ve witnessed firsthand the critical role that charging circuits play in battery – powered devices. In today’s technology – driven world, batteries have become the primary energy source for a vast array of products, from smartphones and laptops to electric vehicles and industrial equipment. The efficiency, safety, and longevity of these batteries largely depend on the charging circuits integrated into the PCB power supplies. In this blog, I’ll delve into the various charging circuits used in PCB power supplies for batteries. PCB Power Supply<\/a><\/p>\n

<\/p>\n

1. Constant Current (CC) Charging Circuit<\/h3>\n

The Constant Current (CC) charging circuit is one of the most fundamental and widely used charging methods. At the beginning of the charging process, a battery typically has a relatively low voltage. The CC charging circuit provides a steady current to the battery regardless of its voltage. This is crucial because when a battery is deeply discharged, applying a high – voltage directly can cause damage.<\/p>\n

The working principle of a CC charging circuit is based on the feedback mechanism. A current – sensing resistor is placed in series with the battery. The voltage across this resistor is proportional to the charging current. An operational amplifier (op – amp) compares this voltage with a reference voltage. If the charging current deviates from the set value, the op – amp adjusts the output of a power transistor to maintain a constant current.<\/p>\n

For example, in a lithium – ion battery charging system, the CC phase is often used at the start. A typical charging current might be set at 1C (where 1C means the current at which the battery would be fully charged in one hour). This phase helps to rapidly bring the battery voltage up to a certain level, but it cannot be continued indefinitely as the battery voltage will continue to rise.<\/p>\n

2. Constant Voltage (CV) Charging Circuit<\/h3>\n

Once the battery voltage reaches a certain threshold during the CC charging phase, the charging process switches to the Constant Voltage (CV) mode. In the CV charging mode, the charging circuit maintains a constant voltage across the battery terminals. As the battery charges, its internal resistance gradually decreases, and the charging current naturally tapers off.<\/p>\n

The main purpose of the CV charging phase is to fully charge the battery without overcharging it. Overcharging can lead to a variety of problems, including reduced battery life, increased heat generation, and in extreme cases, safety hazards such as battery swelling or even explosion.<\/p>\n

A common way to implement a CV charging circuit is by using a voltage – reference source and a voltage – regulating component. A zener diode can be used as a simple voltage reference. The op – amp compares the battery voltage with the reference voltage provided by the zener diode. If the battery voltage is lower than the reference, the op – amp increases the output of the power transistor to boost the charging voltage. Once the battery voltage reaches the reference level, the op – amp adjusts the power transistor to maintain a constant voltage.<\/p>\n

3. CC – CV Charging Circuit<\/h3>\n

Most modern battery charging systems use a combination of CC and CV charging, known as the CC – CV charging circuit. This two – stage charging process takes advantage of the benefits of both CC and CV charging.<\/p>\n

In the first stage, the CC charging circuit quickly charges the battery to a certain voltage level, which is usually around 80% – 90% of its full charge capacity. This rapid charging is efficient and reduces the overall charging time. Once the battery voltage reaches the set threshold, the charging circuit switches to the CV mode. In the CV mode, the battery is slowly charged to its full capacity while ensuring that it does not overcharge.<\/p>\n

For instance, in a smartphone battery charger, the CC – CV charging circuit is commonly employed. When you plug in your nearly – dead smartphone, the charger initially provides a high – current charge (CC mode) to quickly get the phone back to a usable state. As the phone’s battery approaches full charge, the charger switches to CV mode to top – off the battery safely.<\/p>\n

4. Trickle Charging Circuit<\/h3>\n

Trickle charging is a low – current charging method used to maintain the charge of a battery when it is in a standby or storage state. This is especially important for batteries that are subject to self – discharge over time, such as lead – acid batteries.<\/p>\n

A trickle charging circuit provides a very small, constant current to the battery. The current is typically just enough to compensate for the self – discharge of the battery. This helps to keep the battery at a full charge without overcharging it.<\/p>\n

The implementation of a trickle charging circuit can be quite simple. A resistor can be used to limit the charging current to a very low level. For example, a large – value resistor in series with a power source can reduce the current to a few milliamperes, which is suitable for trickle – charging small – capacity batteries.<\/p>\n

5. Pulse Charging Circuit<\/h3>\n

Pulse charging is an advanced charging technique that involves applying a series of high – current pulses to the battery, followed by short rest periods. This method has several advantages over traditional charging methods.<\/p>\n

During the pulse – on period, a high – current pulse is applied to the battery. This high – current pulse can help to break down the internal resistance of the battery and improve the charging efficiency. The rest period allows the battery to recover and reduces the heat generated during charging.<\/p>\n

Pulse charging circuits are often more complex to implement than other charging circuits. They usually involve a pulse – generating circuit that can control the pulse width, frequency, and amplitude. These parameters need to be carefully adjusted according to the type and capacity of the battery.<\/p>\n

6. Fast Charging Circuits<\/h3>\n

With the increasing demand for quick charging in modern devices, fast – charging circuits have become a key area of development. Fast charging circuits aim to significantly reduce the charging time of batteries without sacrificing safety.<\/p>\n

One common approach to fast charging is to increase the charging current during the CC phase. However, this requires careful management of the battery’s temperature and voltage to prevent overheating and overcharging. Another approach is to use multi – stage charging algorithms that optimize the charging process based on the battery’s state of charge.<\/p>\n

For example, Qualcomm’s Quick Charge technology uses a combination of high – voltage and high – current charging in a controlled manner. The charger communicates with the device to determine the optimal charging parameters, allowing for rapid charging while maintaining the safety and longevity of the battery.<\/p>\n

Why Choose Our PCB Power Supplies with These Charging Circuits<\/h3>\n

As a professional PCB power supply supplier, we understand the importance of high – quality charging circuits in battery – powered applications. Our products are designed and manufactured with the latest technologies and strict quality control measures.<\/p>\n

We offer a wide range of PCB power supplies with different charging circuits to meet the diverse needs of our customers. Whether you need a simple CC charging circuit for a low – cost device or a sophisticated fast – charging circuit for a high – end smartphone, we have the solution.<\/p>\n

Our engineering team has extensive experience in designing and developing charging circuits. We can customize the charging circuits according to your specific requirements, ensuring that the power supply is perfectly matched with your battery and device.<\/p>\n

<\/p>\n

In addition, we are committed to providing excellent customer service. We offer technical support throughout the entire product development cycle, from design consultation to after – sales service. If you have any questions or need assistance with your battery charging application, our team is always ready to help.<\/p>\n

PCB Power Supply<\/a> If you are looking for a reliable PCB power supply with high – performance charging circuits, we invite you to contact us for a procurement discussion. We are confident that our products and services will meet your expectations and help you achieve success in your projects.<\/p>\n

References<\/h3>\n