Power Supply Reference Design Advances Set-Top Boxes February 29, 2008
Accelerating set-top box designs, the GreenPoint 50W ac/dc power supply reference design reportedly overcomes the challenges of delivering high efficiency on four output voltages by employing synchronous rectification and soft-switching quasi resonance. The reference design addresses all functional blocks of the adapter, utilizing several of the company’s power management devices. It includes an NCP1308 controller integrating a true current mode modulator and a demagnetization detector and an NCP1586 controller packing a 1A gate driver and an internally set 275-kHz oscillator. Other devices include a TL431A three-terminal programmable shunt regulator diode, MC79L05 100 mA/5V negative voltage regulator, MURA110 1A/100V rectifier, NTD4808N 30V/63A N-channel MOSFET, and an NTB60N06L 60A/60V N-channel logic level MOSFET. All devices are RoHS compliant and individually priced from $0.21 to $0.86 each in volume. ON SEMICONDUCTOR, Phoenix, AZ. (800) 282-9855.
