AS3649

Datasheet - Detailed Descr i p ti on

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1.0-2

19 - 39

8.7 ADC

The internal ADC is used to monitor LED temperature and DIE temperature. To operate the ADC, set the adc_channel (see page 27) and start

the conversion by adc_convert. When adc_convert returns to ‘0’ the result is available in register adc_result (see page 30) (Bits 9...7)and

adc_result_lsbs (Bits 1...0).

The DIE junction temperature measurement returns the value according to Table 6:

The AS3649 supports the I

receiver. The device that controls the message is called a master. The devices that are controlled by the master are referred to as slaves. A

master device that generates the serial clock (SCL), controls the bus access, and generates the START and STOP conditions must control the

bus. The AS3649 operates as a slave on the I

mode (400kHz maximum clock rate) are defined. The AS3649 works in both modes. Connections to the bus are made through the open-drain I/

O lines SDA and SCL.

The following bus protocol has been defined (Figure 27):



Data transfer may be initiated only when the bus is not busy.



During data transfer, the data line must remain stable whenever the clock line is HIGH. Changes in the data line while the clock line is HIGH

are interpreted as control signals.

Accordingly, the following bus conditions have been defined:

Table 6. Junction Temperature Measurement ADC result

Junction Temperature - ºC

ADC Return Value (10bit)

-30

352

-20

343

-10

334

0

325

10

316

20

306

30

297

40

287

50

278

60

268

70

259

80

249

90

239

100

229

110

219

120

209

130

199

140

189

150

179