Low-side MOSFET driver with 3A/5A peak drive
The Texas Instruments LM5111-2MX/NOPB is a dual low-side gate driver designed to drive N-channel MOSFETs in switching power converters. It delivers 3A peak source current and 5A peak sink current, with typical rise and fall times of 14ns and 12ns respectively, which means it can charge and discharge the gate capacitance of a large power MOSFET quickly enough for high-frequency switching — a key parameter for minimizing crossover conduction losses in a synchronous buck or forward converter. Each of the two channels is independent with an inverting input, giving the layout engineer flexibility to route the PWM signal from the controller without extra inversion logic. The supply range of 3.5V to 14V covers common bias rails from a 5V or 12V auxiliary supply, though at the low end the gate drive voltage for the MOSFET will be limited to the supply rail, so check the Rds(on) curve of the selected FET at the actual drive voltage.
Logic compatibility: 3.3V and 5V PWM signals
The logic input thresholds are specified at VIL max 0.8V and VIH min 2.2V, which makes the LM5111-2MX/NOPB directly compatible with both 3.3V and 5V logic families from the controller without level-shifting. A 3.3V PWM signal from a typical MCU or DSP will reliably cross the 2.2V VIH threshold, and the 0.8V VIL ensures noise margin on the low side. The inverting input type means the output goes high when the input is low and vice versa — confirm the polarity matches the controller's PWM output or add an external inverter if needed.
Temperature grade and operating environment
Rated for a junction temperature range of -40°C to 125°C, the LM5111-2MX/NOPB is suited for industrial power supplies, motor drives, and automotive under-hood environments where the ambient temperature can exceed 85°C. The 8-SOIC package with a 0.154-inch body width (3.90 mm) is a standard footprint that fits most PCB layouts without needing a thermal pad, but at high switching frequencies and with large capacitive loads, the package's thermal impedance should be checked against the total power dissipation from gate charge losses and quiescent current.
Lifecycle and sourcing posture
The LM5111-2MX/NOPB carries an Active product status from Texas Instruments, with ROHS3 compliance.