LM5007 High Voltage (80V) Step Down Switching Regulator
January 2004
LM5007
High Voltage (80V) Step Down Switching Regulator
General Description
The LM5007 Step Down Switching Regulator features all of
the functions needed to implement low cost, efficient, Buck
bias regulators. This high voltage regulator contains an 80 V,
0.7A N-Channel Buck Switch. The device is easy to apply
and is provided in the MSOP-8 and the thermally enhanced
LLP-8 packages. The regulator is based on a hysteretic
control scheme using an on time inversely proportional to
V
IN
. This feature allows the operating frequency to remain
relatively constant with load and input voltage variations. The
hysteretic control requires no control loop compensation,
while providing very fast load transient response. An intelli-
gent current limit is implemented in the LM5007 with forced
off time that is inversely proportional to V
OUT
. This current
limiting scheme reduces load current foldback. Additional
protection features include: Thermal Shutdown, Vcc under-
voltage lockout, gate drive undervoltage lockout, and Max
Duty Cycle limiter.
Features
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Integrated 80V, 0.7A N-Channel Buck Switch
Internal HV Vcc Regulator
No Control Loop Compensation Required
Ultra-Fast Transient Response
On Time Varies Inversely with Line Voltage
Operating Frequency Nearly Constant with Varying Line
Voltage
Adjustable Output Voltage
Highly Efficient Operation
Precision Reference
Low Bias Current
Intelligent Current Limit Protection
Thermal Shutdown
External Shutdown Control
Typical Applications
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Non-Isolated Buck Regulator
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Secondary High Voltage Post Regulator
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+42V Automotive Systems
Package
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MSOP - 8
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LLP - 8 (4mm x 4mm)
Connection Diagram
20078302
8-Lead MSOP, LLP
Ordering Information
Order Number
LM5007MM
LM5007MMX
LM5007SD
LM5007SDX
Package Type
MSOP-8
MSOP-8
LLP-8
LLP-8
NSC Package Drawing
MUA08A
MUA08A
SDC08A
SDC08A
Supplied As
1000 Units on Tape and Reel
3500 Units on Tape and Reel
Available Soon
Available Soon
© 2004 National Semiconductor Corporation
DS200783
www.national.com
NSC [ NATIONAL SEMICONDUCTOR ]
