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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

Status Information Data (SID)

The AS1122 contains an integrated status information register. After latching the correct identifier with a 16 bit data word the input shift register

data is replaced with status information data.

With the next 16 clock cycles the Open LED information, the Overtemperature-Warning and -Error flag as well as the power-on reset (POR) flag

can be read out at pin SDO. The status information data packet is 16 bits wide. Bits 11:0 contain the open LED detection status of each channel.

Bit 12 is the overtemperature-warning flag, bit 13 is the overtemperature-error flag and bit 14 indicates if the POR was triggered. The complete

status information data packet is shown in Figure 34.

Figure 34. Status Information Data Packet Format

Note:

Bit14 (POR) is set to ‘1’ after start-up and after triggering a power-on reset due to a supply voltage drop. Must be set to ‘0’ manually.

Readback the Status Information Data

To read out the SID the read bit in the command data needs to be set to “1”. After the new command data is lachted into the device the SID is

shifted to the SDO register and will be shifted out with the next running clk cycles on CLKI. After keeping the clk low for the time tlow, the device

is reset again and can be programmed with need information.

Figure 35. Reading of the Status Information Register

Setting Maximum Channel Current

tiplied by a factor of 31.5. The maximum output current is calculated as:

Where:

x 31.5

(EQ 3)