Detailed explanation of fast charging solution based on TI controller

　　As mobile phone screens get bigger and bigger, processors become more powerful and multi-core. To ensure battery life, mobile phone battery capacity also increases, which inevitably causes charging time to become longer. How to shorten charging time has become a major bottleneck for mobile phone applications. Fast charging solutions based on different manufacturers have emerged one after another, which can effectively improve charging efficiency in a short period of time.

　　1. Solution diagram

　　TI Solution Block Diagram

　　2. Features of the solution

　　Less than 10mW no-load power consumption capability

Optocoupler feedback 　　for constant voltage (CV) and primary side regulation (PSR) for constant current (CC)

　　±1% voltage regulation and ±5% current regulation at line and load

　　700V start switch

　　100kHz maximum switching frequency enables high power density charger designs

　　Resonant ring valley switching operation for highest overall efficiency

　　Frequency jittering to simplify electromagnetic interference (EMI) compliance

　　Clamped gate drive output for MOSFET

　　Overvoltage, low line and overcurrent protection functions

　　3. Main components of this solution

　　UCC28740  Constant Voltage, Constant Current Flyback Controller with Optocoupler Feedback

　　The UCC28740 isolated flyback power supply controller uses an optocoupler device to provide a constant voltage (CV) to improve transient response to large load steps. Constant current (CC) regulation is achieved through primary side regulation (PSR) technology. The device processes information from the optocoupler feedback and the auxiliary flyback winding to achieve precise, high-performance control of the output voltage and current.

UCC28740 Application Block Diagram

　　Details: UCC28740 Constant Voltage, Constant Current Flyback Controller

　　UCC24610  Secondary-Side Synchronous Rectifier Controller

　　UCC24610 Application Block Diagram

　　Details: UCC24610 Secondary-Side Synchronous Rectifier Controller

　　4.TI solution photos