AN4027 Datasheet, PDF (1/41 Pages) STMicroelectronics – This application note describes the EVL6699-150W-SR demonstration

AN4027
Application note
12 V - 150 W resonant converter with synchronous rectification
using the L6563H, L6699 and SRK2000A
Claudio Spini
Introduction
This application note describes the EVL6699-150W-SR demonstration board features,
a 12 V - 150 W converter tailored to a typical specification of an all-in-one (AIO) computer
power supply or a high power adapter.
The architecture is based on a two-stage approach: a front-end PFC pre-regulator based on
the L6563H TM PFC controller and a downstream LLC resonant half bridge converter using
the new L6699 resonant controller. The L6699 device integrates some very innovative
functions such as self-adjusting adaptive deadtime, anti-capacitive mode protection and
proprietary “safe-start” procedure preventing hard switching at startup.
Thanks to the chipset used, the main features of this power supply are very high efficiency,
compliant with ENERGY STAR^® eligibility criteria for adapters (ENERGY STAR^® rev. 2.0 for
external power supplies) and with the latest ENERGY STAR^® qualification criteria for
computers (ENERGY STAR^® ver. 6.0 for computers). The power supply also has very good
efficiency at light load too and no load input power consumption is very low as well, making
the board compliant with the requirements of the latest European Code of Conduct (CoC)
Tier 2 and EuP Lot 6 Tier 2.
Figure 1. EVL6699-150W-SR: 150 W SMPS demonstration board
April 2014
DocID022604 Rev 3
1/41
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