No. 6266-34/37

LC75804E, LC75804W

Sample Application Circuit 8

1/4 duty, 1/3 bias (for use with large panels)

+5.5V

+5V

*9

C

C

R

R

R

*11

S73

S9

P1/S1

P2/S2

P8/S8

(P1)

(P2)

(S75)

(S76)

(P8)

COM1

COM2

COM3

S74/COM4

VDD

OSC

DO

DI

CL

*10

RES

CE

VLCD1

VLCD2

VLCD

TEST

VSS

S

7

6

/

K

S

2

S

7

5

/

K

S

1

K

S

3

K

S

4

K

I

1

K

I

2

K

I

3

K

I

4

K

I

5

K

S

5

K

S

6

Notes on transferring display data from the controller

When using the LC75804E/W in 1/3 duty, applications transfer the display data (D1 to D228) in three operations, and in

1/4 duty, they transfer the display data (D1 to D300) in four operations. In either case, applications should transfer all of

the display data within 30 ms to maintain the quality of the displayed image.

From the controller

10 k

Ω ≥ R ≥ 1 kΩ

C

≥ 0.047 µF

(general-purpose output ports)

Used with the backlight

controller or other circuit.

To the controller

To the controller

power supply

Key matrix

(up to 30 keys)

*11. The DO pin, being an open-drain output, requires a pull-up resistor. Select a resistance (between 1 to 10 k

Ω) appropriate for the capacitance of

the external wiring so that signal waveforms are not degraded.