2–207

SCF5740/2/4

Table 4a. Display Brightness

Table 4b. Display Brightness

The SCF574X offers a unique Display Power Down feature

which reduces ICC to less than 50

µA. When EF

(Table 5) the display is set to 0% brightness. When in the

Power Down mode data may still be written into the RAM. The

display is reactivated by loading a new brightness Level Con-

trol Word into the display.

Table 5. Power Down

Figure 8. Row and Column Locations for a Character “D”

Op code

D7 D6

Control Word

D5

D4

D3

D2

D1

D0

Hex

Operation

Level

1

1

1

0

0

0

0

0

E0

100%

1

1

1

0

0

0

0

1

E1

53%

1

1

1

0

0

0

1

0

E2

40%

1

1

1

0

0

0

1

1

E3

27%

1

1

1

0

0

1

0

0

E4

20%

1

1

1

0

0

1

0

1

E5

13%

1

1

1

0

0

1

1

0

E6

6.6%

1

1

1

0

0

1

1

1

E7

0.0%

Op code

D7 D6

Control Word

D5

D4

D3

D2

D1

D0

Hex

Operation

Level

1

1

1

0

1

0

0

0

E0

100%

1

1

1

0

1

0

0

1

E1

53%

1

1

1

0

1

0

1

0

E2

40%

1

1

1

0

1

0

1

1

E3

27%

1

1

1

0

1

1

0

0

E4

20%

1

1

1

0

1

1

0

1

E5

13%

1

1

1

0

1

1

1

0

E6

6.6%

1

1

1

0

1

1

1

1

E7

0.0%

Op code

D7 D6

Control Word

D5 D4 D3 D2 D1 D0

Hex

Operation Level

1

1

1

0 1

1

1

1 1

EF

0% brightness

off LED

on LED

Row 0

Row 1

Row 2

Row 3

Row 4

Row 5

Row 6

Previously “on” LED

0 1 2 3 4

Columns

The user can activate four Control functions. These include:

LED Brightness Level, IC Power Down, Prescaler, or Display

Clear. OPCODEs and six bit words are used to initiate these

functions. The OPCODEs and Control Words for the Charac-

ter Address and Loading Column Data are shown in Tables 2

and 3 .

Table 2. Load Character Address

Table 3. Load Column Data

The user can select eight specific LED brightness levels,

Table 4. Depending on how D3 is selected either one (1) for

maximum peak current or zero (0) for 12.5% of maximum

peak current in the control word per Table 4a and 4b, the user

can select 16 specific LED brightness levels. These bright-

ness levels (in percentages of full brightness of the display)

depending on how the user selects D3 can be one (1) or zero

controlled by changing the duty factor of the row strobe

pulse.

Op code

D7 D6 D5

Character

Address

D4 D3 D2 D1 D0

Hex

Operation Load

1

0

1

0

0

0

0

0

A0

Character 0

1

0

1

0

0

0

0

1

A1

Character 1

1

0

1

0

0

0

1

0

A2

Character 2

1

0

1

0

0

0

1

1

A3

Character 3

Op code

D7 D6 D5

Column Data

D4 D3 D2 D1 D0

Operation Load

0

0

0

C0 C1 C2 C3 C4

Row 0

0

0

0

C0 C1 C2 C3 C4

Row 1

0

0

0

C0 C1 C2 C3 C4

Row 2

0

0

0

C0 C1 C2 C3 C4

Row 3

0

0

0

C0 C1 C2 C3 C4

Row 4

0

0

0

C0 C1 C2 C3 C4

Row 5

0

0

0

C0 C1 C2 C3 C4

Row 6