LTC4258 LINER [Linear Technology], LTC4258 Datasheet - Page 6

• Manufacturer Part Number: LTC4258
• Description: Quad IEEE 802.3af Power over Ethernet Controller with Integrated Detection
• Manufacturer: LINER [Linear Technology]

TI I G DIAGRA S
LTC4258
6
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
0
A6
Figure 8. Reading the Interrupt Register (Short Form)
REGISTER ADDRESS BYTE
START BY
MASTER
START BY
MASTER
ALERT RESPONSE ADDRESS BYTE
0
1
A5
Figure 9. Reading from Alert Response Address
SERIAL BUS ADDRESS BYTE
0
FRAME 2
0
A4
R/W ACK
AD3 AD2 AD1 AD0
1
FRAME 1
A3
Figure 7. Reading from a Register
FRAME 1
1
Figure 6. 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
NO ACK BY
MASTER
D2
NO ACK BY
D6
MASTER
D1
D5
1
D0
R/W ACK
DATA BYTE
D4
FRAME 3
ACK
ACK
D3
4258 F09
4258 F08
STOP BY
MASTER
D7
D2
STOP BY
MASTER
ACK BY
SLAVE
D6
D1
ACK BY
SLAVE
D5
D0
DATA BYTE
FRAME 2
D4
ACK
4258 F06
D3
STOP BY
MASTER
D2
NO ACK BY
MASTER
D1
D0
ACK
4258 F07
STOP BY
MASTER
4258p