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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

8 Detailed Description

Serial Interface

The AS1122 features a 4-pin (CLKI, CLKO, SDI, and SDO) serial interface, which can be connected to microcontrollers or digital signal proces-

sors.

The rising edge of the CLKI signal shifts data from pin SDI to the internal register. After all data are clocked in, the serial data are latched into the

and all Data are clocked in.

With the first 8 clk-cycles an 8 bit identifier needs to be send to the device to distinguish between Status Information, Dot Correction, PWM or

command data.

After the internal LD signal the internal counter is set to 0 again and the data are latched into the register according to the prior identifier. If the LD

triggers and the counter has no valid value (80 bit for Dot-Correction, 152 bit for PWM data or 16 bit for command data), the counter is set to 0

but the data will be ignored.

With the falling edge of the CLKO the data is shifted to SDO.

Figure 24. PWM Cycle Timing Diagram