In today's increasingly intelligent portable electronic devices and power tools, charging management chips should not only be efficient and safe, but also have flexible configuration and communication capabilities. CXLB73306 is a fully integrated buck-boost charging management IC that supports I2C interface and automatic fast charging protocol application. It is suitable for 1-4 lithium ion batteries and 1-5 lithium iron phosphate batteries with a maximum charging current of 3A. This article will analyze its architecture, functional configuration and typical applications in depth.
-
[ CXLB73306 ]"
CXLB73306 intelligent buck-boost charging chip: highly integrated, programmable, fast charge compatible complete power supply solution
In today's increasingly intelligent portable electronic devices and power tools, charging management chips should not only be efficient and safe, but also have flexible configuration and communication capabilities. CXLB73306 is a fully integrated buck-boost charging management IC that supports I2C interface and automatic fast charging protocol application. It is suitable for 1-4 lithium ion batteries and 1-5 lithium iron phosphate batteries with a maximum charging current of 3A. This article will analyze its architecture, functional configuration and typical applications in depth.
1. Chip Overview and Technical Highlights
CXLB73306 have significant advantages in integration, intelligent control and safety protection:
· Complete set success rate pathBuilt-in 4-switch MOSFET, current detection and loop compensation, greatly simplifying the peripheral circuit.
· Wide input voltage: 3.6V ~ 21V,BAT terminal withstand voltage 30V, suitable for various power supply environments.
· I2C programmable interface: Support flexible configuration of charging parameters, including current, voltage, protection threshold, etc.
Automatic fast charging application: Automatically identify and apply for fast charging voltage (9V/12V) through DP/DM pin to improve charging efficiency.
· Multiple intelligent loops: Including CC/CV, temperature adjustment, input adaptation, etc., the system runs more reliably.
Detailed explanation of 2. core functions
2.1. Intelligent charging management and I2C control
The CXLB73306 supports complete TC/CC/CV three-stage charging, and the key parameters can be adjusted in real time through I2C:
· Current elimination charging: Activate with low current when battery voltage <67% VCV.
· Constant current charging: The current can be set together with I2C through RS resistor, formula:
Default VICC = 50mV, supporting 1.25mV step adjustment.
· Constant voltage chargingFloat voltage is set by external FB divider resistor and I2C:
2.2. Input adaptive and fast charge protocol.
· input adaptive: Set the input voltage drop point through the VSEN pin to prevent the adapter from overloading.
· Automatic fast charging application: The chip automatically applies for 9V or 12V input through DP/DM, and returns to 5V if it fails, which is compatible with various fast charging protocols.
2.3. Temperature protection compatible with JEITA
NTC Configuration: Support dual temperature windows (low temperature 70% REGN, high temperature 47.5% REGN), JEITA1/JEITA2 mode can be selected through I2C:
· JEITA1: The charging current is reduced to 50% at low temperature and the floating voltage is reduced at high temperature.
· JEITA2: In addition to current and voltage regulation, the high temperature section further limits the current to 60% ICC.
2.4. Status indication and interrupt output
2.4.1. STAT Pin：
· Charging: low level (LED on)
· Full: high resistance (LED off)
· Abnormal: 1.5Hz flicker
2.4.2. INT PinOpen-drain output, support system interrupt response, real-time reporting of faults and state changes.
3. I2C Register Configuration Overview
CXLB73306 provide rich I2C register, address is 0x4C, support single byte and continuous read and write:
| Register | Function |
|---|---|
| REG[0]-[2] | System status reading (including interrupt flag) |
| REG[8] | Setting of charging termination current and current elimination current |
| REG[9] | Battery Cell Number, CV Voltage Setting |
| REG[A] | NTC mode, REGN voltage, LED behavior |
| REG[B] | Constant current, current elimination conversion point |
| REG[C] | Charging enable, timeout setting, frequency jitter control |
| REG[D] | Input voltage, VSEN adaptation point |
For example:
· Set 4 batteries, 4.2V/section: REG[9] = 0b00011011
· Enable NTC[1:0] for JEITA2:REG[A] = 0b10
4. typical application scenarios
CXLB73306 is widely used in the following areas:
· Smart Bluetooth Speaker: Support fast charging and multiple batteries to enhance user experience.
· Power Tools & Toys: 3A high current fast recharging, suitable for high power scenarios.
· Electronic Cigarettes and Portable Medical DevicesPrecise voltage and temperature control to ensure safety.
· Interphone and Emergency Equipment: Wide input voltage adaptability, suitable for outdoor changeable environment.
5. packaging and design points
5.1. Encapsulation form: QFN4x4-32L, with good heat dissipation and welding process.
5.2. Thermal resistance parameters: & theta;JA = 52 ℃/W, it is recommended to cooperate with the heat dissipation via design.
5.3. Layout recommendations：
· The large current paths (VIN, SW, BAT) are as short and wide as possible.
· RS resistors should be placed in close proximity to the CSP/CSN to reduce noise interference.
· The FB sampling line should be directly connected to the positive electrode of the battery to reduce the line loss error.
6. Typical Application Schematic Diagram
Why did 7. choose CXLB73306?
With its highly integrated, flexible I2C control and automatic fast charging protocol support, CXLB73306 has become an ideal choice for smart device charging management. Whether developing a new generation of portable devices or upgrading existing power systems, the chip provides an efficient, reliable and safe charging solution.
About JTM-IC
JTM-IC (official website:jtm-ic.com) Focus on the development and sales of high-performance power management chips, providing customers with full-process services from selection to technical support. CXLB73306 is one of our recommended intelligent buck charging chip, welcome to visit the official website for more product information and technical information.
