IX2120

R02

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7

1.9 IX2120 Typical Application

The IX2120 is a 1200V half bridge gate driver for high

voltage IGBTs and MOSFETs. Three input signals

(HIN, LIN, and SD) determine the state of the gate

driver outputs (HO and LO). HIN controls HO via a

high voltage interface. The high voltage interface is

integrated into the bootstrap supply by using two 600V

diodes (DD1 and DD2).

A two-stage bootstrap supplies current to the high side

and mid level circuitry. The two bootstrap circuits are

identical, and careful board layout and positioning of

the bootstrap components are required. Resistors

RD1 and RD2 form a resistive divider to keep the mid

supply very near the center of the high voltage supply

range. High value resisters (5M

) are recommended

to minimize power dissipation. The two-stage

bootstrap supply reduces the high side gate drive

application circuit shown is:

M2.

The high side bootstrap capacitor selection is a

function of the switching frequency and the on-time

insure adequate supply current:

and:

V

DD

V

SS

VHV

COM

M1

1200V

M2

1200V

DR2

1200V

DR1

1200V

RB1

5

RB2

5

R12

4.7

R22

4.7

R11

47

R21

47

V

S

1

V

B

2

N/C

3

HO

4

N/C

5

N/C

6

N/C

7

N/C

8

N/C

9

V

DD

10

HIN

11

SD

12

LIN

13

V

SS

14

LO

15

N/C

16

COM

17

N/C

18

V

CC

19

N/C

20

N/C

21

V

SM

22

V

BM

23

V

SM

24

N/C

25

N/C

26

N/C

27

N/C

28

IX2120

DG2

25V

DG1

25V

DB1

DB2

DD2

600V

DD1

600V

600V

600V

C1

1

µF

V

CC

HIN

SD

LIN

25V

CB1

0.33

µF

25V

CB2

0.33

µF

25V

C3

1

µF

25V

RD2

5M

RD1

5M

20VV

CC

V

BSUV+

2V

F

V

CE sat

++





CB1

I

QBS

t

ONTIME

V

CC

V

BSUV+

2VF

V

CE sat

++



–

---------------------------------------------------------------------------------------------





CB2

I

QBMSM

t

ONTIME

V

CC

V

BSUV+

2VF

V

CE sat

++



–

---------------------------------------------------------------------------------------------



