LM3478Q Datasheet | National Semiconductor

Description The LM3478 is a versatile Low-Side N-Channel MOSFET controller for switching regulators. It is suitable for use in topologies requiring a low side MOSFET, such as boost, flyback, SEPIC, etc. Moreover, the LM3478 can be operated at extremely high switching frequency in order to reduce the overall solution size. The switching frequency of the LM3478 can be adjusted to any value between 100k Hz and 1MHz by using a single external resistor. Current mode control provides superior bandwidth and transient response, besides cycle-by-cycle current limiting. Output current can be programmed with a single external resistor. The LM3478 has built in features such as thermal shutdown, short-circuit protection, over voltage protection, etc. Power saving shutdown mode reduces the total supply current to 5µA and allows power supply sequencing. Internal soft-start limits the inrush current at start-up. Key Specifications - Wide supply voltage range of 2.97V to 40V - 100k Hz to 1MHz Adjustable clock frequency - ±2.5% (over temperature) internal reference - 10µA shutdown current (over temperature) Features - LM3478Q in MSOP-8 package is AEC-Q100 qualified and manufactured on an Automotive Grade Flow - 8-lead Mini-SO8 (MSOP-8) and SO-8 packages - Internal push-pull driver with 1A peak current capability - Current limit and thermal shutdown - Frequency pensation optimized with a capacitor and a resistor - Internal softstart - Current Mode Operation - Undervoltage Lockout with hysteresis Applications - Distributed Power Systems - Battery Chargers - Offline Power Supplies - Tele Power Supplies - Automotive Power Systems Typical Application Circuit Typical High Efficiency Step-Up (Boost) Converter © 2011 National Semiconductor Corporation 101355 .national. LM3478/LM3478Q Connection Diagram 8 Lead Mini SO8 Package (MSOP-8 Package) 8 Lead SO-8 Package (SO-8 Package) Package Marking and Ordering Information Order Number LM3478MM LM3478MMX...