Data Sheet

AD5172/AD5173

I2C INTERFACE

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Rev. J | 17 of 22

WRITE MODE

Table 10. AD5172 Write Mode

S

0

1

0

1

1

1

1

W

A

A0 SD

T

0

OW

X

X

X

A

D7 D6 D5 D4 D3 D2 D1 D0

A

P

Slave address byte

Instruction byte

Data byte

Table 11. AD5173 Write Mode

S

0

1

0

1

1

AD1 AD0 W

A

A0 SD

T

0

OW

X

X

X

A

D7 D6 D5 D4 D3 D2 D1 D0

A

P

Slave address byte

Instruction byte

Data byte

READ MODE

Table 12. AD5172 Read Mode

S

0

1

0

1

1

1

1

R

A

D7 D6 D5 D4 D3 D2 D1 D0

A

E1

E0

X

X

X

X

X

X

A

P

Slave address byte

Instruction byte

Data byte

Table 13. AD5173 Read Mode

S

0

1

0

1

1

AD1 AD0

R

A

D7 D6 D5 D4 D3 D2 D1 D0

A

E1 E0

X

X

X

X

X

X

A

P

Slave address byte

Instruction byte

Data byte

SDA BITS DESCRIPTIONS

Table 14. SDA Bits Descriptions

Bit

Description

S

Start condition.

P

Stop condition.

A

Acknowledge.

AD0, AD1

Package pin-programmable address bits.

X

Don’t care.

W

Write.

R

Read.

A0

RDAC subaddress select bit.

SD

Shutdown connects wiper to B terminal and open circuits the A terminal. It does not change the contents of the wiper register.

T

OTP programming bit. Logic 1 programs the wiper permanently.

OW

Overwrites the fuse setting and programs the digital potentiometer to a different setting. Upon power-up, the digital

potentiometer is preset to either midscale or fuse setting, depending on whether the fuse link was blown.

D7, D6, D5, D4, D3, D2, D1, D0

Data bits.

E1, E0

OTP validation bits.

00 = ready to program.

10 = fatal error. Some fuses not blown. Do not retry. Discard this unit.

11 = programmed successfully. No further adjustments are possible.

I2C CONTROLLER PROGRAMMING

Write Bit Patterns

Figure 47. Writing to the RDAC Register—AD5172