15
LED/LCD BACKLIGHT CONTROL CIRCUIT WITH MFT
0
S5U1C17801T1100 HARDWARE MANUAL
EPSON
37
(SOFTWARE EVALUATION TOOL FOR S1C17801)
15
LED/LCD Backlight Control Circuit
with MFT
0
The SVT
17801
is equipped with a LED that can be controlled by MFT
0
. The following diagram shows how the
EEPROM is connected to the SVT
17801
.
DIC-152-6P
1
1
5
3
5
3
2
6
4
2
4
G
V
V
DD
J12 11pin
(LCD backlight)
V
DD
JP3
JP3
MFT0
U20
TS5A3166
R90
470
LED3
LTW-170TK
C65
0.1µF
LCD_BL_ON
LCD_BL_PWM
D201_PWM
S1C17801
Fig.
15
.
1
Connection Circuit between MFT
0
and LED/LCD Backlight
Pre-stage switching IC (TS
5
A
3166
) is switched by changing phase in MFT
0
H/L areas, and brightness of the LED
can be changed visually by turning ON and OFF the backlight of LED and LCD panel repeatedly in accordance
with the MFT
0
phase.
∗
MFT
0
is an I/O port with
12
mA of drive current. A circuit shown in the figure
15
.
1
.has a pre-stage switch IC,
which however can be replaced simply by a
470
Ω
resistor for direct drive. (The drive current in this case is ap-
proximately
7
mA.)
Summary of Contents for S5U1C17801T1100
Page 4: ......