Overview
The BQ24725A, produced by Texas Instruments, is a high-efficiency, synchronous battery charger designed for multi-chemistry battery charging applications. It is particularly suited for space-constrained designs due to its low component count. This charger supports the charging of one to four series Li+ cells and features SMBus host control for programmable input current, charge current, and charge voltage. The BQ24725A utilizes internal charge pumps to drive n-channel MOSFETs, enabling automatic system power source selection between the adapter and battery.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package | VQFN (RGR) | - |
| Pins | 20 | - |
| Operating Temperature Range | -40 to 85 | °C |
| Switching Frequencies | 615kHz, 750kHz, 885kHz | - |
| Charge Voltage Accuracy | ±0.5% up to 19.2V | - |
| Charge Current Accuracy | ±3% up to 8.128A | - |
| Input Current Accuracy | ±3% up to 8.064A | - |
| Adapter Current or Charge Current Amplifier Output Accuracy | ±2% | - |
| AC Adapter Operating Range | 4.5V-24V | - |
| Off-state Battery Discharge Current | 5µA | - |
| Adapter Standby Quiescent Current | 0.65mA (0.8mA max) | - |
Key Features
- SMBus host-controlled NMOS-NMOS synchronous buck converter with programmable switching frequencies (615kHz, 750kHz, 885kHz)
- Automatic N-channel MOSFET selection of system power source from adapter or battery driven by internal charge pumps
- Enhanced safety features for over voltage protection, over current protection, battery, inductor, and MOSFET short circuit protection
- Programmable input current, charge voltage, and charge current limits
- Integrated soft start and loop compensation
- Real-time system control on ILIM pin to limit charge current
- Programmable battery depletion threshold and battery LEARN function
- Programmable adapter detection and indicator
Applications
The BQ24725A is designed for multi-chemistry battery charging applications, particularly in space-constrained environments. It is suitable for a variety of devices that require efficient and reliable battery charging, such as:
- Portable electronics (laptops, tablets, smartphones)
- Power tools and equipment
- Electric vehicles and hybrid vehicles
- Medical devices requiring precise battery management
Q & A
- What is the BQ24725A?
The BQ24725A is a high-efficiency, synchronous battery charger produced by Texas Instruments.
- What types of batteries does the BQ24725A support?
The BQ24725A supports the charging of one to four series Li+ cells.
- What are the programmable switching frequencies of the BQ24725A?
The BQ24725A has programmable switching frequencies of 615kHz, 750kHz, and 885kHz.
- What safety features does the BQ24725A include?
The BQ24725A includes enhanced safety features for over voltage protection, over current protection, battery, inductor, and MOSFET short circuit protection.
- How accurate is the charge voltage of the BQ24725A?
The charge voltage accuracy of the BQ24725A is ±0.5% up to 19.2V.
- What is the operating temperature range of the BQ24725A?
The operating temperature range of the BQ24725A is -40 to 85°C.
- What is the AC adapter operating range of the BQ24725A?
The AC adapter operating range of the BQ24725A is 4.5V-24V.
- Does the BQ24725A have integrated soft start and loop compensation?
Yes, the BQ24725A has integrated soft start and loop compensation.
- How does the BQ24725A control charge current in real-time?
The BQ24725A controls charge current in real-time through the ILIM pin.
- What is the off-state battery discharge current of the BQ24725A?
The off-state battery discharge current of the BQ24725A is 5µA.
