1 Features
• Operating Input Voltage Range: 6 V to 95 V
• Integrated 100-V, N-Channel Buck Switch
• Internal VCC 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
• 8-Pin VSSOP and WSON Packages
• Create a Custom Design Using the LM5008 With
the WEBENCH® Power Designer

2 Applications
• Non-Isolated Telecommunication Buck Regulators
• Secondary High-Voltage Post Regulators
• 48-V Automotive Systems

3 Description
The LM5008 350-mA step-down switching converter
features all of the functions needed to implement a
low-cost and efficient buck regulator. This highvoltage
converter has an integrated 100-V N-channel
buck switch and operates over an input voltage range
of 9 V to 95 V. The device is easy to implement and
is provided in the 8-pin VSSOP and the thermally
enhanced 8-pin WSON packages. The converter
uses a hysteretic control scheme with a PWM on-time
inversely proportional to VIN. This feature allows the
operating frequency to remain relatively constant. The
hysteretic control requires no loop compensation. An
intelligent current limit is implemented with forced offtime,
which is inversely proportional to VOUT. This
scheme ensures short-circuit protection while
providing minimum foldback. Other protection
features include: thermal shutdown, VCC undervoltage
lockout, gate drive undervoltage lockout, and
maximum duty cycle limiter.