11

Schottky Selection

swing during the dead time between turning off the lower

MOSFET and turning on the upper MOSFET. The diode

must be a Schottky type to prevent the lossy parasitic

MOSFET body diode from conducting.

It is acceptable to omit the diode and let the body diode of

the lower MOSFET clamp the negative inductor swing, but

efficiency will drop one or two percent as a result. The

diode's rated reverse breakdown voltage must be greater

than the maximum input voltage

+12V

PGND

HIP6004A

GND

LGATE

UGATE

PHASE

BOOT

+5V OR LESS

NOTE:

NOTE:

Q1

Q2

+

-

FIGURE 10. UPPER GATE DRIVE - DIRECT VCC DRIVE OPTION

D2

HIP6004A