AS1170 datasheet(30/53 Pages) AMSOSRAM

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AS1170

Detailed description

Datasheet

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DS001083

• v2-00 • 2024-Feb-05

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The following bus protocol has been defined:

•

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:

Bus not busy

Both data and clock lines remain HIGH.

Start data transfer

A change in the state of the data line, from HIGH to LOW, while the clock is HIGH, defines a

START condition.

Stop data transfer

A change in the state of the data line, from LOW to HIGH, while the clock line is HIGH, defines

the STOP condition.

Data valid

The state of the data line represents valid data when, after a START condition, the data line is

stable for the duration of the HIGH period of the clock signal. The data on the line must be

changed during the LOW period of the clock signal. There is one clock pulse per bit of data.

Each data transfer is initiated with a START condition and terminated with a STOP condition.

The number of data bytes transferred between START and STOP conditions are not limited,

and are determined by the master device. The information is transferred byte-wise and each

receiver acknowledges with a ninth bit.

Acknowledge

Each receiving device, when addressed, is obliged to generate an acknowledge after the

reception of each byte. The master device must generate an extra clock pulse that is

associated with this acknowledge bit.

A device that acknowledges must pull down the SDA line during the acknowledge clock pulse

in such a way that the SDA line is stable LOW during the HIGH period of the acknowledge-

related clock pulse. Of course, setup and hold times must be taken into account. A master

must signal an end of data to the slave by not generating an acknowledge bit on the last byte

that has been clocked out of the slave. In this case, the slave must leave the data line HIGH to

enable the master to generate the STOP condition.

AS1170 Datasheet(PDF) 30 Page - ams-OSRAM AG