Buck converters enable smarter power regulation

November 19, 2014 // By Graham Prophet
For low output voltage power regulation in digital TV, monitor and other high density point-of-load system architectures, Diodes Inc. has a series of synchronous buck converters employing adaptive constant on-time (AdCOT) control; the AP65450, AP65452 and AP65552 promise high DC output accuracy, high efficiency and fast transient response.

For the 4A rated AP65450 converter, the AdCOT control supports seamless transition between a continuous conduction mode (CCM) at high loads to a discontinuous conduction mode (DCM) at light loads. The 4A AP65452 and 5A AP65552 variants are designed to remain in CCM to help achieve better system noise reduction and filtering.

Up to 92% efficient and with the added option of automatic light loading to further improve performance, the converters help to simplify compliance with regional low power consumption regulations. In addition, their 4.5V to 18V, operating voltage range will suit 5V, 9V and 12V bus systems.

The devices' high switching frequency of 650 kHz - fixed for the AP65452 and AP65552, variable for the AP65450 under low load conditions – combined with the AdCOT control, enables designers to achieve good output stability while shrinking PCB size, through the use of fewer and smaller external inductive and capacitive components. To help save more space, the three devices are provided in the SO-8EP package. The buck converters incorporate a wide range of protection features including, under voltage lockout, thermal shutdown and over current protection.

The AP65450, AP65452 and AP65552 are priced at $0.78 (10,000).

Diodes; www.diodes.com