LM5008_09 Datasheet, PDF (1/16 Pages) National Semiconductor (TI) – High Voltage (100V) Step Down Switching Regulator

LM5008
April 21, 2009
High Voltage (100V) Step Down Switching Regulator
General Description
The LM5008 Step Down Switching Regulator features all of
the functions needed to implement a low cost, efficient, Buck
bias regulator. This high voltage regulator contains an 100 V
N-Channel Buck Switch. The device is easy to implement 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. The hysteretic control requires no loop compensa-
tion. An intelligent current limit is implemented with forced
OFF time, which is inversely proportional to Vout. This
scheme ensures short circuit protection while providing min-
imum foldback. Other protection features include: Thermal
Shutdown, V_CC under-voltage lockout, Gate drive under-volt-
age lockout, and Max Duty Cycle limiter
Features
■ ^{Integrated 100V, N-Channel buck switch}
■ ^{Internal V}_CC ^regulator
■ ^{No loop compensation required}
■ ^{Ultra-Fast transient response}
■ ^{On time varies inversely with line voltage}
■ ^{Operating frequency remains constant with varying line}
voltage and load current
■ ^{Adjustable output voltage}
■ ^{Highly efficient operation}
■ ^{Precision internal reference}
■ ^{Low bias current}
■ ^{Intelligent current limit protection}
■ ^{Thermal shutdown}
Typical Applications
■ ^{Non-Isolated Telecommunication Buck Regulator}
■ ^{Secondary High Voltage Post Regulator}
■ ^{+42V Automotive Systems}
Package
■ ^{MSOP - 8}
■ ^{LLP - 8 (4mm x 4mm)}
Connection Diagram
20097902
8-Lead MSOP, LLP
Ordering Information
Order Number
LM5008MM
LM5008MMX
LM5008SD
LM5008SDX
LM5008SDC
LM5008SDCX
Package Type
MSOP-8
LLP-8
NSC Package Drawing
MUA08A
SDC08A
SDC08B
Supplied As
1000 Units on Tape and Reel
3500 Units on Tape and Reel
1000 Units on Tape and Reel
4500 Units on Tape and Reel
1000 Units on Tape and Reel
4500 Units on Tape and Reel
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