September 2011

Doc ID 18164 Rev 2

1/27

AN3303

Application note

Secondary-side rectification for an LLC resonant converter

featuring the SRK2000

Introduction

The EVLSRK2000 is a family of demonstration boards designed for the evaluation of the

SRK2000 in LLC resonant converters with synchronous rectification (SR).

The first part of this application note is a brief description of the IC features while the second

is dedicated to the board description. Finally, some considerations regarding circuit

optimization and performance are given.

This board was realized in four different configurations depending on the mounted SR

MOSFETs. Different board codes are shown in Table 1:

Figure 1.

EVLSRK2000: smart driving control for an LLC resonant converter

Table 1.

Demonstration board ordering codes

Ordering code

SR MOSFET P/N

MOSFET

package

EVLSRK2000-L-40

STL140N4LLF5

PowerFLAT™

2.75 m

Ω

40 V

EVLSRK2000-L-60

STL85N6F3

PowerFLAT™

5.70 m

Ω

60 V

EVLSRK2000-D-40

STD95N4F3

DPAK

5.80 m

Ω

40 V

EVLSRK2000-S-40

STS15N4LLF3

SO-8

5.00 m

Ω

40 V

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