AUIR08152S

8

Rev. A8.0

2015-11-09

Examples of system schematics with HVIC

This section shows how the AUIR08152S can be driven by IR High Voltage IC (HVIC).

All the examples refer to an inverter leg; floating voltage sources to supply the high side AUIR08152S are

named Vcch and Veeh, while voltage sources to supply the low side AUIR08152S are named Vccl and Veel.

In the examples, a 7V negative Veeh(l) is shown; this is usually enough to keep even big die size IGBT firmly

clamped in their OFF state during dV/dt transients; in case the IGBTs do not require a negative gate voltage,

Veeh(l) sources can simply be shorted to their relevant IC GND (h or l ).

It is straightforward to say that, when multiple legs are considered, floating supplies must have galvanic isolation

between each other (and w.r.to low side); low side supplies could be shared between the different legs but the

choice if using multiple or shared low side supplies mostly depend upon the system layout.

Especially important in the emitter impedance Zl, as shown in the figures. Non negligible value of the emitter

inductance creates imbalance between the emitter returns and may suggest using separate supplies also for the

low side gate drivers.

Example1 : IGBT gate driving by AUIRS2181S and two AUIR08152S buffer ICs.

AUIRS2181S

AUIR08152S

AUIR08152S

Vcc

HIN

LIN

COM

Vb

HO

Vs

LO

Vcch

Veeh

Vcc

IN

LPM

OUTH

OUTL

DC+

Vee

GND

Cb

Zl

Zl

DC-

Rin

Ron

Roff

Roff

Ron

GND

Vee

Vcc

Vcc

LPM

IN

Rin

VccL

VeeL

OUTH

OUTL

15V

15V

7V

7V

Cb

Figure A-1

The AUIRS2181S is a 8 pin SOIC and does not have separate COM (power GND) and Vss (signal GND) pins.

Therefore, COM is directly connected to the GND of the low side buffer IC but special care has to be taken when

layouting power and control section.