7.3.10 Power MOSFET Gate Drivers

The LM27402 gate driver impedances are low enough to perform effectively in high output current applications where large die-size or paralleled MOSFETs with correspondingly large gate charge, Q_G, are used. Measured at V_VDD = 4.7 V, the LM27402's low-side driver has a low impedance pulldown path of 1 Ω to minimize the effect of dv/dt induced turn-on, particularly with low gate-threshold voltage MOSFETs. Similarly, the high-side driver has 1.7-Ω and 1.2-Ω pull-up and pulldown impedances, respectively, for faster switching transition times, lower switching loss, and greater efficiency.

Furthermore, there is a proprietary adaptive deadtime control on both switching edges to prevent shoot-through and cross-conduction, minimize body diode conduction time, and reduce body diode reverse recovery related losses. The LM27402 is fully compatible with discrete NexFET™ Power Block MOSFETs from TI.