AD5245

Rev. 0 | Page 11 of 16

Table 5. Write Mode

S

0

1

0

1

1

0 AD0 W

A

X

RS SD

X

X

X

X

X

A

D7 D6 D5 D4 D3 D2 D1 D0

A

P

Slave Address Byte

Instruction Byte

Data Byte

Table 6. Read Mode

S

0

1

0

1

1

0

AD0

R

A

D7

D6

D5

D4

D3

D2

D1

D0

A

P

Slave Address Byte

Data Byte

S = Start Condition

P = Stop Condition

A = Acknowledge

X = Don’t Care

W = Write

R = Read

SD = Shutdown connects wiper to B terminal and open

circuits A terminal. It does not change contents of wiper

register.

D7, D6, D5, D4, D3, D2, D1, D0 = Data Bits

PS

P

S

SCL

SDA

SCL

FRAME 1

FRAME 2

START BY

MASTER

ACK BY

AD5245

SLAVE ADDRESS BYTE

STOP BY

MASTER

INSTRUCTION BYTE

SDA

0

1

0

1

1

0

AD0

R/W

XRS

X

X

X

X

X

1

9

19

D7

D6

D5

D4

D3

D2

D1

D0

ACK BY

AD5245

FRAME 3

DATA BYTE

1

9

ACK BY

AD5245

SD

Figure 37

. Writing to the RDAC Register

NO ACK

BY MASTER

SCL

SDA

0

1

0

1

1

0

AD0

R/W

D7

D6

D5

D4

D3

D2

D1

D0

1

9

1

9

FRAME 1

FRAME 2

START BY

MASTER

ACK BY

AD5245

SLAVE ADDRESS BYTE

RDAC REGISTER

STOP BY

MASTER

Figure 38. Reading Data from a Previously Selected RDAC Register in Write Mode