6.3

Supply pins and UVLO function

The VCCx supply pin supplies current to the low-side section of the gate driver and to the integrated bootstrap

diode used to charge the bootstrap capacitor. During output commutations, the average current used to provide

gate charge to the high-side and low-side MOSFETs flow through these pins.

The VCC1 and VCC2 pins separately supply power to the two drivers, even if they are usually connected together

at the power supply in final applications.

The PWD5F60 VCCx supply voltage is continuously monitored by undervoltage lockout (UVLO) circuits that turn

UVLO circuitry turns on the high-side or low-side MOSFET according to the input status as soon as the supply

Two separate UVLO circuits monitor VCC1 and VCC2 so that when a UVLO occurs on a single rail, only the

corresponding half bridge MOSFETs are turned off.

6.4

Dead time

The PWD5F60 automatically inserts a DT dead time on each half bridge. This avoids shoot-through as a

MOSFET gate discharges completely before charging starts on the other MOSFET gate.

The DT value is set by the resistor placed between the DTx pin and GNDx, as shown in Figure 4..

The minimum dead time value set with a 0 Ω resistor is normally sufficient to avoid shoot-through between high

side and low side.

Some applications, like those operating with soft turn-on commutations at low current seeking maximum

efficiency, might benefit from a longer dead time. The PWD5F60 lets you set the dead time for each half bridge for

maximum flexibility.

PWD5F60

Supply pins and UVLO function

DS12543 - Rev 1

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