Texas Instruments LM3478 Low-Side MOSFET Controller IC, 1A, VSSOP-8

The Texas Instruments LM3478MM/NOPB is a versatile, high-efficiency low-side N-channel MOSFET controller designed for switching regulator applications. Engineered to deliver superior performance in a compact package, it is an ideal solution for advanced power management designs requiring precise control and robust protection features.

This controller is specifically suited for topologies that utilise a low-side MOSFET, such as boost, flyback, and SEPIC converters. A key advantage is its ability to operate at extremely high switching frequencies, up to 1 MHz, which allows for a significant reduction in the size of external inductors and capacitors, leading to a more compact overall solution size. The switching frequency is easily adjustable between 100 kHz and 1 MHz using a single external resistor, providing designers with exceptional flexibility.

Employing current mode control architecture, the LM3478 offers excellent bandwidth and transient response, alongside cycle-by-cycle current limiting for enhanced stability and safety. The output current can be conveniently programmed with another single external resistor. Comprehensive built-in protection features include thermal shutdown, short-circuit protection, and over-voltage protection, ensuring reliable operation under demanding conditions.

For power-sensitive applications, a power-saving shutdown mode reduces the total supply current to just 5 µA and facilitates power supply sequencing. An internal soft-start function limits inrush current at start-up, protecting both the controller and the load. The device incorporates an internal push-pull driver with a 1A peak current capability, under-voltage lockout with hysteresis, and a highly accurate ±2.5% internal voltage reference over temperature.

As a green product compliant with environmental standards (containing no antimony or bromine), the LM3478 is a responsible choice for modern electronics. Its robust feature set,