AN2827

Examples of register setup for each mode

Doc ID 15047 Rev 1

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8.5

Example 5: flash pulse longer than 1.5 s

Suppose the targeted value of the flash current is 240 mA. The task is to make a single flash

pulse with a 4-second duration.

FTIM must be reloaded into the COMMAND REGISTER before the internal flash timer

reaches zero. This guarantees that the flash will continue and not stop after 1.5 seconds.

The first packet must also contain the DIMMING REGISTER data if this data is different from

that which was used in the previous operation.

Packet 1

Sets flash mode with a 1.5 s duration and the proper dimming.

Packet 2

Sets flash mode with a 1.5 s duration. Dimming data is not reset since it is the same as for

Packet 1.

Packet 3

Sets flash mode with a 1.5 s duration. Dimming remains the same.

Packet 4

Sets flash mode with a 1 s duration. Dimming remains the same.

Table 26.

I²C data packet for activating flash mode

Byte

Hex

Binary

Comment

1

62

01100010

Device address + R/W bit

2

00

00000000

Command register address

3

DF

11011111

Data of the command register

4

05

00000101

Data of the dimming register

Table 27.

Byte

Hex

Binary

Comment

1

62

01100010

Device address + R/W bit

2

00

00000000

Command register address

3

DF

11011111

Data of the command register

Table 28.

Byte

Hex

Binary

Comment

1

62

01100010

Device address + R/W bit

2

00

00000000

Command register address

3

DF

11011111

Data of the command register