MC34270 Datasheet, PDF (10/12 Pages) Motorola, Inc – LIQUID CRYSTAL DISPLAY AND BACKLIGHT INTEGRATED CONTROLLER

MC34270 MC34271
Figure 14. EL PANEL Drive Circuit
2.2 M
160 k
8.25 k
Vin 6.0 V
MC34270 or MC34271
SW1
32
ÎÎÎÎ ^EN1
26
VDD
8 Drv1
÷2
31 Sync
Circuit #1 Bias Supply
En
S
Q
R
÷N
OSC
9.1 k ₃₀ RT
Vref
Vref
0.1 27 1.25 V
µF
S
2 ^Ref1
Q
R
D1
7
S1 6
ELD ^{400 Hz}
9
0.1
µF
VDD
11
Mode
10
D2
18
S2 19
+
10 µF
MR856
8
0.22 µF
200 V
34
4T 4T
#36 #36
65
120T
1 #36
15 k
7 _MPSA44
120T
#36
2
1.0 k
MR856
EL
PANEL
10
MTP3055EL
2.2 k
4.3 M 15 pF ₃ FB1
22 k
4 Comp1
SS1
1.0 k
0.1 µF ⁵
10 k MMBT2907
DS1
1
1.0 k ^DAC
Ref2
23
VB
22 _FB2
Comp2
21 _SS2
20
8.2 k
DS2
24
25 EN2
VA
28
BIAS
Gnd
29
Î^VDD
VDD2
Circuit #2
Bias Supply
VB
VB
17
V0
V0
16
V1
15
V2
14
VDD2
V3
13
VDD2
V4
12
V1
V2
V3
LCD
Display
V4
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
10
MOTOROLA ANALOG IC DEVICE DATA