6.3

VCC UVLO protection

Undervoltage protection is available on VCC and BOOT supply pins. In order to avoid intermittent operation, a

hysteresis sets the turn-off threshold with respect to the turn-on threshold.

When VCC voltage goes below the VCCthOFF threshold, all the outputs are switched off, both LVG and HVG.

When VCC voltage reaches the VCCthON threshold, the driver returns to normal operation and sets the LVG

outputs according to actual input pin status; HVG is also set according to input pin status if the corresponding VBO

section is not in UVLO condition. The FAULT output is kept low when VCC is in UVLO condition. The following

figures show some examples of typical operation conditions.

Figure 11. VCC power ON and UVLO, LVG timing

VCC

VCCthON

VCCthOFF

FAULT

LVG

LIN

UVLO VCC

0V

0V

0V

0V

VCC CHARGE

Vil

Vih

Figure 12. VCC power ON and UVLO, HVG timing

VCC

VCCthON

VCCthOFF

FAULT

HVG-OUT

HIN

UVLO VCC

0V

0V

0V

0V

VBO

VBOthON

VBOthOFF

0V

Vil

Vih

PWD5T60

Functional description

DS14558 - Rev 2

page 13/27