Datasheet

Device description L6730 - L6730B
20/52 Doc ID 11938 Rev 3
5.7 Driver section
The high-side and low-side drivers allow for the use of different types of power MOSFETs
(also multiple MOSFETs to reduce the R
DSON
), maintaining fast switching transitions. The
low-side driver is supplied by V
CCDR
while the high-side driver is supplied by the BOOT pin.
A predictive dead time control avoids MOSFETs cross-conduction maintaining very short
dead time duration (see Figure 13.).
The control monitors the phase node in order to sense the low-side body diode recirculation.
If the phase node voltage is less than a certain threshold (–350 mV typ.) during the dead
time, it will be reduced in the next PWM cycle. The predictive dead time control does not
work when the high-side body diode is conducting because the phase node does not go
Figure 12. Sink mode disabled: Inductor current during and after soft-start (L6730)
Vout
Vss
Vcc
I
L