Datasheet

LTC2977
19
2977fa
For more information www.linear.com/LTC2977
OPERATION
SLAVE ADDRESS COMMAND CODE DATA BYTE LOWWr A A A P
2977 F02
S
7 8 8 1
DATA BYTE HIGH
81 1 1 1 11
A
SLAVE ADDRESS COMMAND CODE DATA BYTEWr A A A P
2977 F03
S
7 8 8 1
PEC
81 1 1 1 11
A
SLAVE ADDRESS COMMAND CODE DATA BYTE LOWWr A A A P
2977 F04
S
7 8 8 1
DATA BYTE HIGH
8
PEC
811 1 1 1 11
A A
Figure 1b. Write Byte Protocol
Figure 2. Write Word Protocol
Figure 3. Write Byte Protocol with PEC
Figure 4. Write Word Protocol with PEC
SLAVE ADDRESS Wr A A P
2977 F05
S
7 81 1 1 11
COMMAND CODE
SLAVE ADDRESS COMMAND CODE PECWr A A A P
2977 F06
S
7 8 81 1 1 1 11
Figure 5. Send Byte Protocol
Figure 6. Send Byte Protocol with PEC
Figure 1a. PMBus Packet Protocol Diagram Element Key
SLAVE ADDRESS COMMAND CODE DATA BYTEWr A A A P
2977 F01b
S
7 8 81 1 1 1 11
SLAVE ADDRESS COMMAND CODEWr A A P
2977 F01a
S
7 81 1 1 11
S
Sr
Rd
Wr
x
A
P
PEC
START CONDITION
REPEATED START CONDITION
READ (BIT VALUE OF 1)
WRITE (BIT VALUE OF 0)
SHOWN UNDER A FIELD INDICATES THAT THE
FIELD IS REQUIRED TO HAVE THE VALUE OF x
ACKNOWLEDGE (THIS BIT POSITION MAY BE 0
FOR AN ACK OR 1 FOR A NACK)
STOP CONDITION
PACKET ERROR CODE
MASTER TO SLAVE
SLAVE TO MASTER
CONTINUATION OF PROTOCOL
...
x x