LM5007 Datasheet, PDF (1/17 Pages) National Semiconductor (TI) – High Voltage (80V) Step Down Switching Regulator

LM5007
www.ti.com
SNVS252F – SEPTEMBER 2003 – REVISED MARCH 2013
High Voltage (80V) Step Down Switching Regulator
Check for Samples: LM5007
FEATURES
1
•2 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
• VSSOP-8 and WSON-8 (4mm x 4mm) Packages
APPLICATIONS
• Non-Isolated Buck Regulator
• Secondary High Voltage Post Regulator
• +42V Automotive Systems
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 VSSOP-8 and the thermally enhanced WSON-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
intelligent 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 undervoltage
lockout, gate drive undervoltage lockout, and Max
Duty Cycle limiter.
Connection Diagram
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SW
2
BST
3
RCL
4
RTN
8
VIN
7
VCC
6
RON
5
FB
Figure 1. 8-Lead VSSOP or WSON
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2
PRODUCTION DATA information is current as of publication date.
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