ltc4259a Linear Technology Corporation, ltc4259a Datasheet - Page 7

• Manufacturer Part Number: ltc4259a
• Description: Quad Ieee 802.3af Power Over Ethernet Controller With Ac Disconnect
• Manufacturer: Linear Technology Corporation

TI I G DIAGRA S
SDA
SCL
W U
0
START BY
MASTER
1
SERIAL BUS ADDRESS BYTE
0
SDA
SCL
AD3 AD2 AD1 AD0
FRAME 1
0
START BY
MASTER
1
SERIAL BUS ADDRESS BYTE
R/W ACK
W
SDA
0
SCL
SDA
SCL
AD3 AD2 AD1 AD0
FRAME 1
A7
ACK BY
SLAVE
0
START BY
MASTER
0
START BY
MASTER
A6
Figure 9. Reading the Interrupt Register (Short Form)
REGISTER ADDRESS BYTE
ALERT RESPONSE ADDRESS BYTE
0
1
Figure 10. Reading from Alert Response Address
A5
SERIAL BUS ADDRESS BYTE
0
FRAME 2
0
A4
R/W ACK
AD3 AD2 AD1 AD0
1
FRAME 1
A3
Figure 8. Reading from a Register
FRAME 1
1
Figure 7. Writing to a Register
A2
A7
0
ACK BY
SLAVE
ACK BY
A1
SLAVE
A6
REGISTER ADDRESS BYTE
0
A0
A5
R/W ACK
R/W ACK
ACK
FRAME 2
A4
A3
0
D7
ACK BY
SLAVE
ACK BY
SLAVE
A2
0
1
D6
SERIAL BUS ADDRESS BYTE
ACK BY
1
REPEATED
START BY
MASTER
A1
SLAVE
0
D5
SERIAL BUS ADDRESS BYTE
A0
0
AD3
FRAME 2
DATA BYTE
D4
FRAME 2
AD3 AD2 AD1 AD0
ACK
AD2 AD1 AD0
FRAME 1
D3
D7
D2
NO ACK BY
NO ACK BY
D6
MASTER
MASTER
D1
D5
1
D0
R/W ACK
DATA BYTE
D4
FRAME 3
ACK
ACK
D3
4259A F10
4259A F09
STOP BY
MASTER
D7
D2
STOP BY
MASTER
ACK BY
SLAVE
D6
D1
ACK BY
SLAVE
D5
D0
DATA BYTE
FRAME 2
D4
ACK
4259A F07
LTC4259A
D3
STOP BY
MASTER
D2
NO ACK BY
MASTER
D1
D0
ACK
4259A F08
STOP BY
MASTER
4259afb
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