5.3

Control logic

The device integrates a control logic providing two input strategies. The driving method is selected according to

DT/MODE pin status:

•

DT/MODE connected to the ground through an RDT resistor: digital inputs provide enable and input lines for

each half-bridge and an internal deadtime is generated according to RDT value (ENx/INx mode).

•

DT/MODE shorted to ground: digital inputs provide high and low-side driving lines for each half-bridge, no

deadtime is internally generated (INHx/INLx mode). In any case, the high and low-side outputs of same half-

bridge cannot be simultaneously driven high because of the integrated interlocking function.

Note:

The DT/MODE pin status must not be changed during device operation.

All the input lines have an internal pull-down to guarantee the low logic level even if no driving input is present.

Table 7. INxL and INxH inputs truth table

INxH

INxL

GHSx

GHLx

‘x’ Half-bridge condition

L

L

L

L

Disabled

L

H

L

H

Low-side on

H

L

H

L

High-side on

H

H

L

L

Disabled (interlocking)

Table 8. ENx and INx inputs truth table

ENx

INx

GHSx

GLSx

‘x’ Half-bridge condition

L

X

L

L

Disabled

H

L

L

H

Low-side on

H

H

H

L

High-side on

Note:

X: don't care

5.3.1

Deadtime

When the DT/MODE pin is connected to the ground through an RDT resistor (ENx/INx mode selected), the device

internally generates a deadtime between the MOSFET turn-off and the turn-on of the opposite one.

Input pulses shorter than the deadtime cause an immediate turn on of the gate driver, back to the former status as

shown in Figure 13.

STDRIVE101

Control logic

DS13472 - Rev 1

page 17/32