Application information

HVLED001B

26/33

DS12748 Rev 2

7.3

Gate driver

The output stage, connected to VCC potential and capable of 300 mA source and 600 mA

sink current, is suitable to drive high current MOSFETs. The resulting managed power can

be greater than 150 W.

7.4

IC supply management

The IC's voltage supply is managed by the UVLO circuitry together with high voltage startup

unit and reference generators. These logics also define supply currents during different

operating conditions.

7.4.1

VCC supply management

The IC is designed to operate with a range of supply voltage to ensure an optimum gate

driving. An active limiting device is embedded to prevent low energy fluctuations to bring the

VCC voltage above the technological constraints.

Both the active mode and the low consumption mode exhibit very low supply currents in

order to meet energy saving regulation.

The VCC pin can be driven independently from the HVSU pin's connection, for example

when auxiliary supply voltage is present. In this case the HVSU pin will be used solely to

monitor input voltage.

A bulk capacitor, having a capacitance of around 22 μF, followed by a ceramic capacitor,

having a typical capacitance of 100 nF and connected very tight to the VCC pin, are

necessary to properly sustain the VCC voltage during all operating phases.