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L6382D

filament heating when they are supplied by independent winding.

current from Vcc to PIN HSB when LSG in ON. A patented integrated bootstrap section replaces an

external bootstrap diode. This section together with a bootstrap capacitor provides the bootstrap voltage

to drive the high side power MOSFET. This function is achieved using a high voltage DMOS driver

which is driven synchronously with the low side external power MOSFET. For a safe operation, current

flow between BOOT pin and Vcc is always inhibited, even though ZVS operation may not be ensured.

5.4 INTERNAL LOGIC, OVER CURRENT PROTECTION (OCP) AND INTERLOCKING FUNCTION.

The DIM (

are low during the described start-up procedure; the DIM block controls the L6382D behaviour during both

When the voltage on pin CSI overcomes the internal reference of 0.5V (typ.) the block latches the fault

condition: in this state the OCP block forces low both HSD and LSD signals while CSO will be forced high.

This condition remains latched until LSI and HSI are simultaneously low and CSI is below 0.5V.

This function is suitable to implement an over current protection or hard-switching detection by using an

external sense resistor.

As the voltage on pin CSI can go negative, the current must be limited below 2mA by external compo-

nents.

Another feature of the DIM block is the internal interlocking that avoids cross-conduction in the half-

bridge FET's: if by chance both HGI and LGI input's are brought high at the same time, then LSG and HSG

are forced low as long as this critical condition persists.