PWM Controllers Target AC-DC Adapter Apps
Mon, 03/07/2011 - 9:48am
ON Semiconductor expanded its portfolio of AC-DC power solutions for home electronics with the introduction of the NCP1234 and NCP1236 family of fixed frequency pulse width modulation (PWM) current mode controllers. These solutions are targeted at AC-DC adapter applications for laptop/notebook computers, LCD displays, printers and household consumer electronics. The family allows high performance offline power supplies to be designed into systems, while minimizing the footprint and board space area required. Using a high voltage process technology, they integrate multiple features such as over power compensation, brownout (NCP1236 only) and ramp compensation without increasing power dissipation or adding external components. High voltage Dynamic Self-Supply (DSS) technology enables direct connection to the line voltage eliminating the need for startup resistors. This technology combined with the family’s ability to automatically decrease frequency at light loads before entering skip mode, ensures maximum efficiency across the entire load range.