Offline flyback power ICs achieve sub-30-mW standby power for 5- to 100-W adapters

March 17, 2014 // By Graham Prophet
Texas Instruments has introduced two flyback power solutions that achieve the highest energy efficiency and lowest standby power consumption for 5- to 100-W AC/DC power supplies. The UCC28910 700-V flyback switcher and UCC28630 high-power, Green-Mode controller expand TI's leading portfolio of flyback controllers covering the complete power range of AC/DC adapters and power supplies.

Combining high density with high efficiency, TI's UCC28910 switcher with integrated high-voltage power MOSFET achieves very low stand-by power consumption for 5- to 10-W designs and features the lowest constant-current output tolerance of 5%, providing an accurate, maximum current across different input voltages. The UCC28630 controller's ability to support primary side regulation (PSR) technology improves reliability in 10- to 100-W power supplies.

The UCC28910 achieves 80% average efficiency in 7.5-W designs and 78% efficiency at 10% load. The UCC28630 achieves greater than 88% average efficiency in 65-W to 130-W designs, and 87% efficiency at a 10% load.

Stand-by power consumption meets and exceeds European Commission (EC) standby regulations, including the IPP 5-star mobile charger rating of less than 30-mW power performance for no-load, stand-by power and the EC Code of Conduct (Tier 1 and 2) for 5- to 10-W designs (UCC28910) and for 30-W designs (UCC28630).

Both flyback solutions support primary side regulation and eliminate the need for an optocoupler feedback circuit to increase reliability.

You can use and adapt any of six tested PowerLab reference designs using the UCC28910:

PMP9045 - 85VAC-265VAC Input for 5V, 7.5W low-cost, small flyback

PMP9171 – Primary-side regulated flyback for Universal AC Input and 15V, 0.25A output

PMP9115 – Primary-side regulated flyback for universal AC input and 15V, 0.33A output

PMP9061 – Primary-side regulated flyback for universal AC input and 16 V, .25A output

PMP9176 – Ultra-wide input voltage range AC-DC buck converter

PMP9053 – Universal 3-phase, AC input with 3.3V, 0.5A output (functional isolation)

PMP8583 – Universal input to 12.2V at 500mA non-isolated quasi-resonant flyback

In a 7-pin SOIC package, the UCC28910 is priced at $0.75 and the UCC28630 is priced at $0.60, (1000). Evaluation boards, UCC28910FBEVM and UCC28630EVM, are $99.

TI; www.ti.com/ucc28910-pr or www.ti.com/ucc28630-pr