Digital power controller is fast and software-configurable
By Margery Conner -- EDN, December 22, 2005
Ron Van Dell, president and chief executive officer of Primarion, likes to preface his introduction of the company’s new digital power-conversion and -management family with a detailed explanation of exactly what ”digital power” is—and isn’t. “If you put a serial interface on an analog controller, that doesn’t make it a digital controller. It’s an analog controller with a serial interface. A true digital controller allows you to both configure and communicate with it over an interface and doesn’t require any outside hardware changes.” With this definition, you must be able to both configure and debug the design through a GUI for the power controller/manager to merit the designation “digital.”
Primarion’s entry into the growing field of digital-power-management and -control ICs for nonisolated dc/dc converters is the PX7510, which incorporates fast on-chip nonvolatile memory, as well as the industry-standard PMBus to allow software-controlled configuration and real-time system monitoring. The IC’s combination of true digital management and nonvolatile memory enable it to allow for less-than-ideal off-chip components and their effect on the control loop. According to Van Dell, this ability breaks the analog paradigm that dictates that overall dc/dc converter precision can never be better than the precision of the surrounding resistors and capacitors. In addition to external tolerances, the controller can calibrate for other variations, such as drift and aging, allowing designs to use lower tolerance, lower cost external components.
The PX7510 operates on a 5V supply and has a frequency-switching range of 150 kHz to 2 MHz. It can share current and thus can adapt from single-phase to a multiphase operation by synchronizing as many as four controllers to balance the power supply current between phases. The PX7510 is available in an ROHS (reduction-of-hazardous-substances)-compliant, 535-mm, 32-lead micro-lead-frame package. Prices start at $1.75 (1000).
Primarion, www.primarion.com.
