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AS1122

Datasheet - D e t a i l e d D e s c r i p t i o n

The input shift register shifts greyscale data into the greyscale register for all channels simultaneously. The complete greyscale data format con-

sists of 12 x 12 bit words, which forms a 144-bit wide data packet (see Figure 32) plus the 8-bit for the identifier.

Figure 32. PWM Data Packet Format

The PWM data is only valid if the exact identifier byte was send. Otherwise the data will be ignored.

Command Data

In the command register of the AS1122 some configuration of the device can be done. After sending the correct identifier the 8 bits of the com-

mand register are accessible.

The complete status information data packet is shown in Figure 33.

Figure 33. Command Packet Format

Table 7. Command Register Format

Bit

Bit Name

Default

Access

Bit Description

7:5

-

000

n/a

4

Read SID

0

W

0: normal operation

1: read Status Information Register (SID)

3

OPEN Test

0

W

0: no test is running

1: start OPEN test

2

Over Temperature

Power down

0

W

0: If an overtemperature condition occurs the OUTn are NOT switched off

automatically.

1: If an overtemperature condition occurs the OUTN are switched off

automatically.

1

Display One Time

0

W

0: The PWM is running endless

1: The PWM is running for one cycle

0

OEN

0

W

0: This bit must be ‘0’ as well as bit3 of the last valid identifier to turn ON all

channels.

1: all channels are OFF