LM3475
LM3475 is Hysteretic PFET Buck Controller manufactured by National Semiconductor.
Description
The LM3475 is a hysteretic P-FET buck controller designed to support a wide range of high efficiency applications in a very small SOT23-5 package. The hysteretic control scheme has several advantages, including simple system design with no external pensation, stable operation with a wide range of ponents, and extremely fast transient response. Hysteretic control also provides high efficiency operation, even at light loads. The PFET architecture allows for low ponent count as well as 100% duty cycle and ultralow dropout operation.
Features n n n n n n n n n Easy to use control methodology 0.8V to VIN adjustable output range High Efficiency (90% typical) ± 0.9% ( ± 1.5% over temp) feedback voltage 100% duty cycle capable Maximum operating frequency up to 2MHz Internal Soft-Start Enable pin SOT23-5 package
Applications n n n n n n n TFT Monitor Auto PC Vehicle Security Navigation Systems Notebook Standby Supply Battery Powered Portable Applications Distributed Power Systems
Typical Application Circuit
© 2004 National Semiconductor Corporation
DS200701
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Connection Diagram
Top View
5 Lead Plastic SOT23-5 NS package Number MF05A
Package Marking and Ordering Information
Order Number LM3475MF LM3475MFX Package Type SOT23-5 SOT23-5 Package Marking S65B S65B Supplied As: 1000 units on Tape and Reel 3000 units on Tape and Reel
Pin Description
Pin Name FB GND EN VIN PGATE Pin Number 1 2 3 4 5 Description
Feedback input. Connect to a resistor divider between the output and GND. Ground. Enable. Pull this pin above 1.5V (typical) for normal operation. When EN is low, the device enters shutdown mode. Power supply input. Gate drive output for the external PFET.
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Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN PGATE FB EN Storage Temperature Power...