What are the categories of charging chips?

Charging chips are key components responsible for managing the battery charging process in electronic devices. They come in various categories and can be roughly classified into the following categories based on their different functions, application scenarios, and technical characteristics:
1、 Classified by charging method
Linear charging chip
Principle: Constant current/constant voltage charging is achieved by adjusting the voltage drop of internal transistors, operating in linear mode.
Features: Simple structure, low cost, low EMI interference, but low efficiency (especially noticeable heating under high voltage difference), suitable for low-power scenarios (such as headphones, wristbands).
Typical applications: Charging single lithium batteries and button batteries.
Switching charging chip (PWM/PFM)
Principle: Efficient energy conversion is achieved through high-frequency switch action (Buck/Boost topology), combined with feedback circuit to achieve constant current/constant voltage control.
Features: High efficiency (85% -95%), support for high-power charging, but complex design and high cost.
Typical applications: Charging large capacity batteries such as mobile phones, tablets, laptops, etc.
2、 Classified by charging protocol
Universal Charging Protocol Chip
Supporting protocols: Basic protocols such as USB BC1.2 and DCP (dedicated charging port).
Features: Wide compatibility, but slow charging speed (usually ≤ 5V/2A).
Application scenarios: low-power devices, basic charging requirements.
Fast charging protocol chip
Support agreement:
Private protocols: Qualcomm QC (Quick Charge), Huawei SCP/FCP, OPPO VOOC, vivo FlashCharge, etc.
Universal protocols: USB PD (Power Delivery), PPS (Programmable Power Supply), Samsung AFC, etc.
Features: Fast charging is achieved by dynamically adjusting voltage/current (such as PD 3.0 supporting up to 20V/5A).
Application scenarios: High end mobile phones, tablets, game consoles, and other devices that require rapid energy replenishment.
3、 Classified by charging architecture
Single chip integration solution
Features: Integrating charging management, power path management, battery protection and other functions into one chip, simplifying peripheral circuits.
Advantages: Save PCB space, reduce costs, and improve reliability.
Typical chips: TI BQ25895 (supporting QC3.0/PD), Southchip SC8815 (supporting bidirectional fast charging).
Separate architecture
Composition: Charging IC+Battery Protection IC+Power MOSFET and other standing devices.
Advantages: High flexibility, allowing for the selection of devices with different performance according to needs.
Disadvantages: Complex design and high cost.
4、 Classified by special functions
Wireless charging chip
Principle: Based on electromagnetic induction (Qi standard) or magnetic resonance technology, wirelessly transmit electrical energy to the battery.
Composition: transmitter (TX) chip+receiver (RX) chip.
Typical chips: IDT P9221 (transmitter), TI BQ51013 (receiver).
Battery balancing chip
Function: When multiple batteries are connected in series, the voltage of each battery is balanced through active or passive means to extend the battery life.
Application scenarios: power tools, drones, energy storage systems, etc.
Multi port charging chip
Function: Supports multiple USB ports for simultaneous charging and dynamic power allocation.
Typical chip: Yingjixin IP6538 (supports 2C1A three port fast charging).
5、 Classified by battery type
Li-ion Battery Charger
Support types: Lithium ion (Li ion), Lithium polymer (Li Po), Lithium iron phosphate (LiFePO4), etc.
Key parameters: Pre charge threshold (usually 3.0V), constant voltage cut-off voltage (such as 4.2V/4.35V), charging current (such as 1A-5A).
Super capacitor charging chip
Features: Supports fast charging and discharging with high voltage (such as 5.5V) and high current (such as 10A), suitable for peak power compensation scenarios.
6、 Classified by packaging form
SOP/QFN packaging: suitable for small and medium power scenarios, with average heat dissipation performance.
BGA packaging: high integration, suitable for high-power, multi pin requirements (such as car charging modules).
WLCSP (Wafer Level Chip Packaging): The smallest size, suitable for wearable devices.
Key considerations for selecting charging chips
Battery parameters: voltage range, capacity, charging current requirement.
Efficiency and heat dissipation: High power scenarios require attention to thermal design (such as adding heat sinks or using thermal conductive adhesive).
Protocol compatibility: Select supported protocols based on the target market (such as QC/SCP for domestic devices and PD for export devices).
Cost and volume: Consumer electronics tend to prefer high integration solutions, while industrial equipment may choose a discrete architecture.
Future Trends
GaN (Gallium Nitride) technology: increases switching frequency, reduces volume, and lowers heat generation.
Bidirectional charging: Supports discharging batteries to external devices (such as charging a laptop to a mobile phone).
Intelligent charging management: integrating AI algorithms to dynamically adjust charging strategies based on battery status.
Based on the above classification, suitable charging chips can be selected according to specific application scenarios to balance performance, cost, and reliability.