650V, 230mΩ GaN half-bridge with integrated driver, protection and current sense

The LMG2656 is a 650V 230mΩ GaN power-FET half bridge. The LMG2656 simplifies design, reduces component count, and reduces board space by integrating half-bridge power FETs, gate drivers, bootstrap FET, and high-side gate-drive level shifter in a 6mm by 8mm QFN package.

Programmable turn-on slew rates provide EMI and ringing control. The low-side current-sense emulation reduces power dissipation compared to the traditional current-sense resistor and allows the low-side thermal pad to be connected to PCB power ground.

The high-side GaN power FET can be controlled with either the low-side referenced gate-drive pin (INH) or the high-side referenced gate-drive pin (GDH). The high-side gate-drive signal level shifter reliably transmits the INH pin signal to the high-side gate driver in challenging power switching environments. The smart-switched GaN bootstrap FET has no diode forward-voltage drop, avoids overcharging the high-side supply, and has zero reverse-recovery charge.

The LMG2656 supports converter light-load efficiency requirements and burst-mode operation with low quiescent currents and fast start-up times. Protection features include FET turn-on interlock, under-voltage lockout (UVLO), cycle-by-cycle current limit, and over-temperature shut down. Ultra low slew rate setting supports motor drive applications.