AC/DC Power Conversion Sell Sheet

AC/DC Power Conversion
Low-Power Low-Cost Offline Power Conversion Solutions
Examples
Linear Regulator
LR8 is a high-voltage, low-output current, adjustable linear
regulator. It has a wide operating input voltage range of
13.2–450 V. The output current limit is typically 20 mA.
*
VIN
VOUT
LR8
ADJ
R1
C1
RLOAD
C2
R2
*Required for conditions where VIN is less than VOUT.
Summary
Many applications require their low-power controller
circuits to operate from an offline power source. An AC/
DC converter is also required to provide safety isolation
from the application to the AC line and to meet EMI
emission requirements.
Microchip provides a broad-range of cost-effective
solutions for AC/DC power conversion to help bring a
design to market in the shortest time possible.
Non-Isolated AC/DC Application
An alternative use for the HV9922, originally designed as
an LED driver, is an offline, non-isolated, bias power supply
for line-side circuitry. An example of an application would
be to provide 50 mA bias for a motor drive controller. It will
operate from 85 VAC to 256 VAC, is stable with open and
short-circuit loads and since there is no feedback loop, it
is unconditionally stable.
1
D
Applications
■
■
■
■
■
Smart appliances
Smart meters
Telecom/network equipment
Offline MCU or DSC power supply
Offline SMPS start-up circuits
Available Reference Material
D
6
D7
4
D5
2
U1
HV9922
GND
VDD
C1
0.1 µF
50V
C5
3.3 µF
400V
Varistor
DR
C3
0.1 µF
400V
C4
0.033 µF
400V
RV1
AC1
L2
2.2 mH
1
L1
2
22 mH
D1
MUR160
R1
VOUT+
200 Ω
D2
C2
0.22 µF
50V
D2
VOUT−
AC2
This alternative circuit can be modified to provide high-side
referenced bias, useful for applications like biasing active
current sensing, as shown below.
Datasheets
■ HV9922 Datasheet
■ HV9910B Datasheet
■ LR8 Datasheet
AC
Fuse
+
Surge
Protection
VOUT = VZ
−
Application Notes
■ DN-H02
■ DN-H03
■ AN-D17
CO
VZ
R1
D1
MUR160
L1
22 mH
60 mA
C1
3.3 µF
VDD
C
0.1 µF
1
DR
HV9922
GND
Adjust C1 value to prevent
drop-out. Adjust R1 for
minimum duty cycle of 5%.
Adjust L1 for ripple control.
VZ = < 20 V.
Example of Products
Device
Packages
VIN (V)
LR8N8-G
Linear
12–450
1.2–440
10
−40 to 125
3-pin TO-252,
3-pin TO-92,
3-pin SOT-89
LR12
Linear
12–100
1.2–88
50
−40 to 125
3-pin TO-252,
3-pin TO-92,
8-pin SOIC
Inductorless
80–285 (VAC)
9–50
100
−40 to 125
8-pin SOIC
HV9921/2/3N8-G
Buck
20–400
Adj.
20/50/30
−40 to 125
TO-92, SOT-89
HV9910B
Buck
8–450
Adj.
External FET
−40 to 125
8-pin SOIC,
16-pin SOIC
HV9120/3NG-G
PWM
10–450
Adj.
External FET
−55 to 125
16-pin SOIC,
16-pin PDIP,
20-pin PLCC
Depletion Mode
MOSFETs
BVDSX Min. (V)
RDSON Max.
Min. (mA)
VDSOFF Max. (V)
ü
450
60
120
−3.5
SR086/7
Device
DN3145N8-G
Output Voltage (V) IOUT Max. (mA)
Operation
Temperature (°C)
Topology
Packages
SOT-89
Note: Please refer to Microchip's Analog and Interface Product Selector Guide (DS20001060) for more options and details.
Development Board
HV9922DB2 Demo Board (HV9922DB2)
www.microchip.com/analog
Visit our web site for additional product information and to locate your local sales office.
Microchip Technology Inc. • 2355 W. Chandler Blvd. • Chandler, AZ 85224-6199
Information subject to change. The Microchip name and logo and the Microchip logo are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. All other trademarks
mentioned herein are property of their respective companies. © 2014, Microchip Technology Incorporated. Energizer and other marks are trademarks owned by Energizer. All Rights Reserved. Printed in the
U.S.A. 12/14
DS20005364A
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