The LM5146 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_VCC = 7.5 V, the low-side driver of the LM5146 has a low impedance pulldown path of 0.9 Ω to minimize the effect of dv/dt induced turn-on, particularly with low gate-threshold voltage MOSFETs. Similarly, the high-side driver has 1.5-Ω and 0.9-Ω pullup and pulldown impedances, respectively, for faster switching transition times, lower switching loss, and greater efficiency.

The high-side gate driver works in conjunction with an integrated bootstrap diode and external bootstrap capacitor, C_BST. When the low-side MOSFET conducts, the SW voltage is approximately at 0 V and C_BST is charged from VCC through the integrated boot diode. Connect a 0.1-μF or larger ceramic capacitor close to the BST and SW pins.

Furthermore, there is a proprietary adaptive dead-time control on both switching edges to prevent shoot-through and cross-conduction, minimize body diode conduction time, and reduce body diode reverse recovery losses.