AN2644 datasheet(4/64 Pages) STMICROELECTRONICS

Part #	AN2644

Description	An introduction to LLC resonant

Download	64 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

Logo

4 / 64 page

List of figures

AN2644

4/64

List of figures

Figure 1.

LLC resonant topology schematics and waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Figure 2.

General block diagram of a resonant inverter, the core of resonant converters . . . . . . . . . . 5

Figure 3.

LLC resonant half-bridge schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Figure 4.

LLC resonant half-bridge with split resonant capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Figure 5.

Equivalent schematic of a real transformer (left, tapped secondary; right, single

secondary) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Figure 6.

Example of high-leakage magnetic structures (cross-section) . . . . . . . . . . . . . . . . . . . . . . . 9

Figure 7.

Equivalent schematic of a transformer including parasitic capacitance . . . . . . . . . . . . . . . 12

Figure 8.

Power MOSFET totem-pole network driving a resonant tank circuit in a half-bridge

converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 9.

Detail of Q1 ON-OFF and Q2 OFF-ON transitions with soft-switching for Q2 . . . . . . . . . . 14

Figure 10.

Q2 gate voltage at turn-on: with soft-switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 11.

Q2 gate voltage at turn-on: with hard-switching (no ZVS) . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 12.

Q1 ON-OFF and Q2 OFF-ON transitions with hard switching for Q2 and recovery for

DQ1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 13.

Bridge leg transitions in the neighborhood of inductive-capacitive regions boundary . . . . 17

Figure 14.

Bridge leg transitions under no-load conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Figure 15.

Reference LLC converter for the analysis of the fundamental operating modes . . . . . . . . 21

Figure 16.

Operation at resonance (f = fR1): main waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Figure 17.

Operation above resonance (f > fR1): main waveforms in CCMA operation at heavy load 25

Figure 18.

Operation above resonance (f > fR1): main waveforms in DCMA operation at medium

load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Figure 19.

Operation above resonance (f > fR1): main waveforms in DCMAB operation at light

load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 20.

Operation below resonance (fR2 < f < fR1 , R>Rcrit): main waveforms in DCMAB

operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 21.

Operation below resonance (fR2 < f < fR1, R>Rcrit): main waveforms in DCMB2 operation 32

Figure 22.

Capacitive mode operation below resonance (fR2 < f < fR1, R<Rcrit): main waveforms . . . 35

Figure 23.

No-load operation (cutoff): main waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Figure 24.

Circuit's equivalent schematic under: no-load conditions . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Figure 25.

Circuit's equivalent schematic under: short-circuit conditions. . . . . . . . . . . . . . . . . . . . . . . 38

Figure 26.

Converter's startup: main waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Figure 27.

High-side driving with bootstrap approach and bootstrap capacitor charge path . . . . . . . . 41

Figure 28.

Frequency compensation with an isolated type 3 amplifier (3 poles + 2 zeros) . . . . . . . . 45

Figure 29.

Comparison of gate-charge characteristics with and without ZVS . . . . . . . . . . . . . . . . . . . 48

Figure 30.

Equivalent circuit to analyze the transitions of the half-bridge midpoint node when Q2

turns off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Figure 31.

Voltage of HB node vs time (see Equation 32) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Figure 32.

Resonant current vs time (see Equation 34) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Figure 33.

Capacitance associated to the half-bridge midpoint node . . . . . . . . . . . . . . . . . . . . . . . . . 54

Figure 34.

Coss capacitances vs. half-bridge midpoint's voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Figure 35.

Simplified schematic to analyze transition times of the node HB when Q2 turns off . . . . . 56

Figure 36.

Schematization of Q2 turn-off transient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Figure 37.

Input current components in a split-capacitor LLC resonant half-bridge. . . . . . . . . . . . . . . 61

Figure 38.

Timing diagram showing currents flow in the converter of Figure 37 . . . . . . . . . . . . . . . . . 61

Similar Part No. - AN2644

Manufacturer	Part #	Datasheet	Description
STMicroelectronics	AN2640	1Mb / 36P	Intelligent multipower digital ballast for fluorescent lamps
List of Unclassifed Man...	AN2640K	301Kb / 4P	VHD VIDEO DISC PLAYER CHROMA AND LUMINANCE PROCESSING CIRCUIT
STMicroelectronics	AN2641	424Kb / 37P	Using the color LCD controller
	AN2645	529Kb / 36P	Migration and compatibility guidelines for STM8S microcontroller applications
	AN2646	446Kb / 43P	Smartcard interface with the STM8S microcontroller

More results

Similar Description - AN2644

Manufacturer	Part #	Datasheet	Description
ON Semiconductor	AND8085	23Kb / 2P	An Introduction to FST April, 2002 ??Rev. 0
STMicroelectronics	AN3303	2Mb / 27P	Secondary-side rectification for an LLC resonant converter
Microchip Technology	TB003	100Kb / 12P	An Introduction to KELLOQ짰 Code Hopping 1996 - 1999
MPS Industries, Inc.	P6503	462Kb / 1P	HALF BRIDGE LLC RESONANT TRANSFORMER
Shindengen Electric Mfg...	MCZ5207SG	1Mb / 24P	LLC Current resonant bridge controller
Fairchild Semiconductor	AN-4151	1Mb / 17P	Half-bridge LLC Resonant Converter
MPS Industries, Inc.	P6504	463Kb / 1P	HALF BRIDGE LLC RESONANT TRANSFORMER
ON Semiconductor	FAN7688	1Mb / 32P	Advanced Secondary Side LLC Resonant Converter November 2015 Rev. 1.3
STMicroelectronics	AN2142	705Kb / 16P	This document provides an introduction to the Tasking toolchain
STMicroelectronics	AN4240	1Mb / 30P	This application note provides an easy introduction to the usage

More results

AN2644 Datasheet(PDF) 4 Page - STMicroelectronics

AN2644 Datasheet(HTML) 4 Page - STMicroelectronics

Similar Part No. - AN2644

Similar Description - AN2644

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64

Datasheet Download

Link URL