NOA1305

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equal to the threshold (and provided the INT pin is enabled,

see INT_SELECT register).

Changing the INT_THRESH register value can cause the

INT pin to change immediately if the ALS_DATA to

INT_THRESH comparison changes.

Powering down the device will cause the INT pin to

become inactive.

To program a value into the INT_THRESH register, use

the following write command sequence:

1. Issue Start command

0x39 followed by write−bit 0)

3. Issue 0x04 for the INT_THRES_LSB register

address

4. Issue the 8−bit LSB value

5. Issue Stop command

6. Issue Start command

0x39 followed by write−bit 0)

8. Issue 0x05 for the INT_THRES_MSB register

address

9. Issue the 8−bit MSB value

10. Issue Stop command

After a power−down and power−on sequence, wait at least

three integration times for the data to stabilize, before

accessing any ALS_DATA values from NOA1305.

ALS_DATA_LSB and ALS_DATA_MSB Registers

(0x06, 0x07)

The ALS_DATA register holds the ambient light intensity

count from the most recent measurement. The ALS_DATA

two 8−bit registers for the least and most significant bits

(LSB and MSB).

To read the ALS_DATA register, use the following read

command sequence:

1. Issue Start command

0x39 followed by write−bit 0)

3. Issue 0x06 for the INT_DATA_LSB register

address

4. Issue Start command

0x39 followed by read−bit 1)

6. Read the ALS_DATA_LSB byte

7. Read the ALS_DATA_MSB byte

8. Issue Stop command

DEVICE_ID_LSB and DEVICE_ID_MSB Registers

(0x08, 0x09)

The DEVICE_ID register is a pre−programmed register

that describes the device. For the NOA1305, the register

holds the decimal value of 1305 (0x0519). The DEVICE_ID

two 8−bit registers for the least and most significant bits

(LSB and MSB).

To read the DEVICE_ID register, use the following read

command sequence:

1. Issue Start command

0x39 followed by write−bit 0)

3. Issue 0x08 for the DEVICE_ID_LSB register

address

4. Issue Start command

0x39 followed by read−bit 1)

6. Read the DEVICE_ID_LSB byte

7. Read the DEVICE_ID_MSB byte

8. Issue Stop command