ad5259 Analog Devices, Inc., ad5259 Datasheet - Page 16

• Manufacturer Part Number: ad5259
• Description: Nonvolatile, I2c-compatible 256-position, Digital Potentiometer
• Manufacturer: Analog Devices, Inc.

AD5259
I
The following generic, write, read, and store/restore control
registers for the AD5259 all refer to the device addresses listed
in Table 5; the mode/condition reference key (S, P, SA, MA,
NA, W , R, and X) is listed below.
S = Start Condition
P = Stop Condition
SA = Slave Acknowledge
MA = Master Acknowledge
NA = No Acknowledge
W = Write
R = Read
X = Don’t Care
GENERIC INTERFACE
Table 6. Generic Interface Format
S
Table 7. RDAC-to-EEPROM Interface Command Descriptions
C2
0
0
0
1
1
1
WRITE MODES
Table 8. Writing to RDAC Register
S
Table 9. Writing to EEPROM Register
S
Table 10. Activating/Deactivating Software Write Protect
S
In order to activate the write protection mode, the WP bit in Table 10 must be logic high. To deactivate the write protection, the
command must be sent again, except with the WP in logic zero state. WP is reset to the deactivated mode if power is cycled off and on.
2
C-COMPATIBLE FORMAT
7-Bit Device Address
(See Table 5)
Slave Address Byte
7-Bit Device Address
(See Table 5)
Slave Address Byte
7-Bit Device Address
(See Table 5)
Slave Address Byte
7-Bit Device Address
(See Table 5)
Slave Address Byte
C1
0
0
1
0
0
1
C0
0
1
0
0
1
0
Command Description
Operation Between Interface and RDAC.
Operation Between Interface and EEPROM.
Operation Between Interface and Write Protection Register. See Table 10.
NOP.
Restore EEPROM to RDAC.
Store RDAC to EEPROM.
R/W
0
0
0
SA C2 C1 C0 A4 A3 A2 A1 A0 SA D7 D6 D5 D4 D3 D2 D1 D0 SA P
SA 0
SA 0
SA 0
Instruction Byte
Instruction Byte
Instruction Byte
Instruction Byte
0
0
1
0
0
1
Rev. A | Page 16 of 24
0
0
0
0
0
0
0
0
0
AD1 and AD0 are two-state address pins.
Table 5. Device Address Lookup
AD1 Address Pin
0
1
0
1
0
0
0
0
0
0
SA D7 D6 D5 D4 D3 D2 D1 D0 SA P
SA D7 D6 D5 D4 D3 D2 D1 D0 SA P
SA 0
Data Byte
Data Byte
Data Byte
Data Byte
AD0 Address Pin
0
0
1
1
0
0
0
0
0
I
0011000
0011010
1001100
1001110
2
C Device Address
0
WP SA P