Gate driving circuitry

AN4355

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Gate driving circuitry

The L648x devices integrate a programmable gate driving circuitry which allows to drive

a wide range of external N-channel MOSFETs.

The parameters which can be set are listed in Table 3.

Figure 10. Gate driving circuit diagram

Table 3. Gate driving circuit parameters

Parameter

Description

Gate source/sink current

The current used to charge/discharge the gate of the MOSFETs.

Controlled current time

(charging time)

The charging/discharging time of the gate of the MOSFETs.

Turn-off current boost time

The part of the discharging time during which the gate current is forced

to the maximum value.

Deadtime

The time between the turn-off of a MOSFET and the turn-on of the

opposite one.

Blanking time

The time after the MOSFETs commutation where the sensing circuitry is

disabled in order to avoid spurious triggering.