Patent Number: 6,295,217

Title: Low power dissipation power supply and controller

Abstract: An exemplary power supply provides low power dissipation in standby mode by disabling the start-up circuit and by implementing variable frequency operation independent of the feedback signal. A standby mode detection circuit automatically implements the variable frequency operation, and an under voltage lockout signal implements the start-up circuit disable. Once the start time expires or when feedback control enables, the start-up circuit is disabled so that it dissipates negligible power. A voltage controlled oscillator responsive to the rectified DC line voltage provides for variable frequency operation in standby mode. The frequency output of the VCO is inversely proportional to the line voltage--as line voltage increases the switching frequency decreases, which decreases the output power.

Inventors: Yang; Min-Sung (Seoul, KR), Pletcher; Timothy Allen (Eastampton, NJ), Amantea; Robert (Manalapan, NJ), Choi; Jae-Young (Seoul, KR), Yu; Joo-Dong (Kyunngi-Do, KR), So; Jae-Hwan (Kyunngi-Do, KR)

Assignee: Sarnoff Corporation

International Classification: H02M 1/00 (20060101); H02M 3/24 (20060101); H02M 3/335 (20060101); H02M 001/12 ()

Expiration Date: 09/25/2018