LM5007 Datasheet | National Semiconductor

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 VIN. This feature allows the operating frequency to remain relatively constant with load and input voltage variations. The hysteretic control requires no control loop pensation, 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 VOUT. 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. Features n n n n n n n n n n n n n Integrated 80V, 0.7A N-Channel Buck Switch Internal HV Vcc Regulator No Control Loop pensation 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 n Non-Isolated Buck Regulator n Secondary High Voltage Post Regulator n +42V Automotive Systems Package n MSOP - 8 n LLP - 8 (4mm x 4mm) Connection Diagram 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...