Low Standby Power AC Adapter L6562 + L6668 90W 19V/4.7A AC-DC Converter Reference Design.

Low Standby Power AC Adapter L6562 + L6668

90W 19V/4.7A AC-DC Converter Reference Design

90W Adaptor General Features

• Input Voltage range: 100 to 240Vac

• Output Voltage and current: 19V/4.7A

• Power Factor Correction: Above 0.98

• Low Standby < 0.4W at no load condition

• High Efficiency, typical 82% at low line full load

• Latched OVP

L6562 - Power Factor Correction

• Transition Mode Control

• Very Precise Adjustable Output Over

Voltage Protection

• Ultra-Low Startup Current (<70A)

• ON-CHIP Filter ON Current Sense

• Disable Function

• 1% internal reference voltage

• -600mA/+800mA Totem Pole Gate Driver

L6668 - PWM Controller

• Current Mode Controller with

sophisticated standby feature

• On board high voltage startup

• Low quiescent current (<2mA)

• Slope Compensation

• Pulse-by-pulse & Hiccup-Mode OCP

• Interface with PFC Controller

• Disable Function (on/off control)

• Latched Disable for OVP/OTP Function

• Programmable soft start

L6668 – Standby Operation

The device operates in different modes depending on the converter’s load condition

1.) Fixed Frequency at heavy load

2.) Frequency-foldback at medium load

3.) Burst Mode Control with no or very light load.

This MOSFET has to withstand

high stress for short period.

L6668 + L6562 Operation

Points to note:

• PWM is powered up before PFC.

• PFC is switched off during standby mode.

PWM MOSFET has to withstand high stress for a short period of time under low line, full load before bulk capacitor voltage build up!

L6668 -- Programmable Frequency Foldback

L6668 -- Load Dependent Operating Mode

L6668 -- Interface with PFC Controller

L6668 -- Converter Output in Short Circuit

90W Demoboard Schematic

Demoboard Layout

PFC Inductor

Inductance 0.7mH

Main Transformer

Inductance 0.7mH

Demoboard Test Result – Power Factor

PFC

0. 000

0. 100

0. 200

0. 300

0. 400

0. 500

0. 600

0. 700

0. 800

0. 900

1. 000

0. 00 0. 50 1. 00 1. 50 2. 00 2. 50 3. 00 3. 50 4. 00 4. 50 5. 00

A输出电流（）

PFC

Demoboard Test Result – Standby power loss

0.00

50.00

100.00

150.00

200.00

250.00

100 120 140 160 180 200 220 240 260

No Load Power (mW)

Input Voltage (Vac)

Demoboard Test Result – Load Regulation

19.16

19.18

19.20

19.22

19.24

19.26

19.28

19.30

19.32

0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 4.50 5.00

220Vac

100Vac

Output Voltage

Output Current

Demoboard Test Result -- Line Regulation

19.1619.1819.2019.2219.2419.2619.2819.3019.32

100 110 120 130 140 150 160 170 180 190 200 210 220 230 240

0A output current

5A output current

Output Voltage

Input AC Voltage

PFC Waveforms

At 110Vac

Ch.1 Current Waveform Ch2.: Bridge Rectifier output waveform

At 220Vac

Ch.1 Current Waveform Ch2.: Bridge Rectifier output waveform

Main Converter Vdrain Normal Operating Waveform

At 110Vac At 220Vac

Main Converter Vdrain during Short Circuit Condition

At 110Vac At 220Vac

Demoboard BOM

Item Reference Part Description

1 　　 Assembly Dwg.

2 　　 Schematic

3 　 PC Board PC Board,1-Layers,136mm x62mm

4 F101 3.15A/250V fuse

5 RT NTPA78R0LBMB0 Murata NTR

6 RV G471 varistor

7 R101,R102 1.5M resistor

8 R103 22K resistor

9 R104 75K resistor

10 R105 20ohm resistor

11 R106,R107 750K resistor

12 R108,R121 9.1K resistor


14 R111 68K 3W resistor



17 R114 4K resistor

Demoboard BOM

18 R115 2.2K resistor

19 R116 150K resistor





24 R124,R125,R126 2M resistor



27 R201 30ohm 3W resistor




31 R205,R206,R207 1K resistor


33 CX101 0.22uF/275V X2 capacitor

34 CY 2.2nF/400V Murata DE1E3KX222M

35 C101 0.47uF/400V Capacitor

Demoboard BOM

36 C102,C109,C113 10nF/50V Capacitor

37 C103 680nF/50V Capacitor

38 C104,C116 1uF/50V Capacitor

39 C105,C110,C111 100nF/50V Capacitor

40 C112 3.3nF/50V Capacitor

41 C107 82uF/450V 电解电容

42 C108 100uF/35V 电解电容


44 C117 22uF/35V 电解电容

45 C201 1nF/1KV Capacitor

46 C202,C203,C204 1000uF/35V 电解电容

47 C205 220uF/35V 电解电容


49 BR101 KBL810G bridge rectifier

50 D101 STTH310S rectifier

51 D102 P6KE250 rectifier

52 D104 FR107 rectifier

53 D201,D202 STPS20150CT rectifier

Demoboard BOM

54 Z101 20V zener diode

55 Z102 13V zener diode

56 Q101 STP12NM50 MOSFET

57 Q102 STP10NK70Z MOSFET

58 Q103 3904 transistor

59 Q104 3906 transistor

60 Q201 ST TL431 voltage reference

61 COM101 400uH 共模

62 COM102 22mH 共模

63 COM201 360uH 共模

64 L101 22uH 差模色环电感

65 L201 10uH 差模磁棒

66 OPT K817P6 opto-coupler

67 IC101 L6562D PFC IC

68 IC102 L6668 PWM IC

69 TR1 PQ32/20 Transformer

70 TR2 PQ32/20 Transformer

Low Standby Power AC Adapter L6562 + L6668 90W 19V/4.7A AC-DC Converter Reference Design.

Documents

Transcript of Low Standby Power AC Adapter L6562 + L6668 90W 19V/4.7A AC-DC Converter Reference Design.