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AS1121

Datasheet - Detailed Descr i pti on

Setting Dot Correction

The AS1121 can perform independent fine-adjustments to the output current of each channel, i.e., dot correction. Dot correction is used to adjust

brightness deviations of LEDs connected to the output channels (OUT0:OUT15).

The device powers up with the following default seetings: DC = 63 and GS = 4095.

The 16 channels can be individually programmed with a 6-bit word. The channel output can be adjusted in 64 steps from 0 to 100% of the maxi-

Where:

DCn is the programmed dot correction value for output (DCn = 0 to 63);

n = 0 to 15

Dot correction data are simultaneously entered for all channels. The complete dot correction data format consists of 16 x 6-bit words, which

forms a 96-bit serial data packet (see Figure 19). Channel data is put on one by one, and the data is clocked in with the MSB first.

Figure 19. Dot Correction Data Packet Format

Figure 20. Dot Correction Data Input Timing Diagram

DCn

63

(EQ 3)

DC0.0

DC0.5

DC1.0

DC14.5

DC15.0

DC15.5

LSB

DC OUT0

DC OUT14:DC OUT1

...

...

...

DC OUT15

MSB

95

90

89

6

5

0

DCn

MSB-2

DCn

MSB-1

DCn

LSB+1

DCn

MSB

DCn-1

LSB

DCn

LSB

DCn+1

MSB

DCn+1

MSB-1

DCn-1

MSB-1

DCn-1

MSB-2

DCn-1

LSB+1

DCn-1

LSB

DCn

MSB

DCn

MSB-1

DCn

MSB-2

DCn-1

MSB

MODE

SDI

CLK

SDO

LD

Dot Correction Mode

Data Input Cycle n

Dot Correction Mode

Data Input Cycle n +1

12

1

2

1

95

96

GND