Communication interfaces
A3M34SL039 Airfast Power Amplifier Module with Autobias Control, Rev. 0, September 2022
Data Sheet: Technical Data
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I
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C Write and Read combination sequence
Figure 9. I
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C Write and Read combination sequence
9.2.3 I
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C Device ID Read instruction
The Device ID is read only, hardwired in the device and can be accessed as follows:
1. START condition
2. The leader sends the Reserved Device ID I
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C bus address followed by the R/W bit set to ‘0’ (write): ‘1111 1000’.
3. The leader sends the I
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C bus follower address of the follower device it must identify. The LSB is a “don’t care” value. Only
one device must acknowledge this byte (the device that has the I
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C bus follower address).
4. The leader sends a RESTART condition.
Remark:
A STOP condition followed by a START condition resets the follower state machine and the Device ID read cannot
be performed. Also, a STOP condition or a RESTART condition followed by an access to another follower device resets the
follower state machine and the Device ID read cannot be performed.
1. The leader sends the Reserved Device ID I
2
C bus address followed by the R/W bit set to ‘1’ (read): ‘1111 1001’.
2. The Device ID read can be completed, starting with the 12 manufacturer bits (first byte + four MSBs of the second byte),
followed by the nine part identification bits (four LSBs of the second byte + five MSBs of the third byte), and then the three
die revision bits (three LSBs of the third byte).
3. The leader ends the reading sequence by NACKing the last byte, thus resetting the follower device state machine and
allowing the leader to send the STOP condition.
Remark:
The reading of the Device ID can be stopped anytime by sending a NACK.
