Texas Instruments UCG2882x High Frequency QR Flyback Converters
Texas Instruments UCG2882x High-Frequency Quasi-Resonant (QR) Flyback Converters feature a built-in 750V GaN high-electron-mobility transistor (HEMT) with a low Rds(on) of 170mΩ, enabling efficient AC-to-DC power conversion. The UCG2882x is designed for high-power-density applications, such as cell phone fast chargers and notebook adapters. The key feature of this device is its self-bias and auxiliary-less sensing scheme, which eliminates the need for an auxiliary winding and simplifies system design with higher efficiency.
This device also features intelligent mode transition (CCM/QR/DCM), enabling high efficiency across a wide power range and < 30mW standby power consumption. In addition, UCG2882x includes a comprehensive list of protections, including brown-in and brown-out protection, SCP, OVP, OPP, LPS, OFB, and OTP. The cycle-by-cycle current limit enables a fast response to fault conditions, safeguarding the system and improving its reliability. In a small 5mm × 5mm package, the Texas Instruments UCG2882x has dedicated configuration pins, offering more flexibility. Only resistors are needed to tune specific parameters for each system, enabling a platform design with a single device.
Features
- Integrated 750V GaN with 170mΩ Rds(on) option
- Dynamic QR/DCM/CCM modes of operation
- High power density with up to 500kHz switching frequency
- Enable low BoM cost by integration
- Remove auxiliary winding with self-bias
- Integrated input and output voltage sensing
- Integrated current sense
- Integrated HV start-up
- Integrated X-cap discharge
- High efficiency and low EMI performance
- Ultra-low standby power of < 30mW
- Frequency foldback and burst mode
- Valley locking
- Frequency dithering
- Switching slew rate control
- Comprehensive protection features
- Overtemperature protection
- Overvoltage protection
- Short-circuit protection
- Cycle-by-cycle current limit
- Two-level over-power protection with LPS
- Brown-in and brown-out protection
- Open feedback protection
- Flexible configurability through external resistors
- X-cap discharge and CCM mode disable
- Selectable switching slew rate
- Multiple clamping frequency settings
- Fault latch or auto-restart
- Maximum and minimum peak current ratio
- Dithering amplitude
Applications
- USB-PD adapter for portable electronics
- USB wall outlets and docking stations
- Industrial DIN rail power supplies
- Server aux power supplies
Simplified Schematic
