LM3481MMX LM3481MMX/NOPB LM3481QMM Power Path Management IC Switching Controllers

1 Features

• LM3481QMM are Automotive-Grade Products That are AEC-Q100 Grade 1 Qualified (–40°C to +125°C Operating Junction Temperature)

• 10-Lead VSSOP Package

• Internal Push-Pull Driver With 1-A Peak Current Capability

• Current Limit and Thermal Shutdown

• Frequency Compensation Optimized With a Capacitor and a Resistor

• Internal Softstart

• Current Mode Operation

• Adjustable Undervoltage Lockout With Hysteresis

• Pulse Skipping at Light Loads

• Key Specifications

  • – Wide Supply Voltage Range of 2.97 V to 48 V

  • – 100-kHz to 1-MHz Adjustable and Synchronizable Clock Frequency

  • – ±1.5% (Over Temperature) Internal Reference

  • – 10-μA Shutdown Current (Over Temperature)

• Create a Custom Design Using the LM3481 with

  the WEBENCH Power Designer

2 Applications

• Automotive Start-Stop Applications

• Automotive ADAS Driver Information

• One Cell/Two Cell Li-ion Battery Powered Portable Bluetooth Audio Systems

• Notebooks, PDAs, Digital Cameras, and Other Portable Applications

3 Description

The LM3481 device is a versatile Low-Side N-FET high-performance controller for switching regulators. The device is designed for use in Boost, SEPIC and Flyback converters and topologies requiring a low- side FET as the primary switch. The LM3481 device can be operated at very high switching frequencies to reduce the overall solution size. The switching frequency of the LM3481 device can be adjusted to any value between 100kHz and 1MHz by using a single external resistor or by synchronizing it to an external clock. Current mode control provides superior bandwidth and transient response in addition to cycle-by-cycle current limiting. Current limit can be programmed with a single external resistor.

The LM3481 device has built-in protection features such as thermal shutdown, short-circuit protection and overvoltage protection. Power-saving shutdown mode reduces the total supply current to 5 μA and allows power supply sequencing. Internal soft-start limits the inrush current at start-up. Integrated current slope compensation simplifies the design and, if needed for specific applications, can be increased using a single resistor.

Device Information