MC34271

http://onsemi.com

9

Figure 13. EL PANEL Drive Circuit

R

S

Q

Vin 6.0 V

D1

S1

SW1

Sync

Drv1

EN1

ELD

Mode

R

S

Q

RT

SS1

Vref

1.25 V

Ref1

FB1

Circuit #1 Bias Supply

VDD

VDD

Comp1

En

OSC

D2

S2

VB

V0

V1

V2

V3

V4

VDD

Circuit #2

Bias Supply

Ref2

FB2

Comp2

SS2

DS2

EN2

VA

Gnd

BIAS

VB

V2

V3

V4

VDD2

VDD2

VDD2

160 k

16

15

14

13

12

19

18

17

10

11

9

6

7

32

26

8

31

30

27

2

3

4

5

23

22

21

20

24

25

28

29

LCD

Display

÷ 2

÷ N

V1

V0

Vref

DS1

1

MC34271

DAC

VB

EL

PANEL

2.2 M

8.25 k

9.1 k

0.1

µF

4.3 M 15 pF

0.1

µF

8.2 k

1.0 k

400 Hz

0.1

µF

10

2.2 k

MTP3055EL

MR856

10

µF

4T

#36

4T

#36

65

34

MR856

8

7

0.22

µF

200 V

120T

#36

2

1

15 k

1.0 k

NOTES::1. Transformer information TDK Core # PC40EEM12.7/13.7–Z

Bobbin # BEPC–10–118G 2 mil gap. LP = 1.6 µhy.

2. EL PANEL: DUREL

™ 3/SL ORANGE

+

MPSA44

120T

#36

10 k

1.0 k

22 k

MMBT2907