AD5280BRU20 Analog Devices Inc, AD5280BRU20 Datasheet - Page 15

• Manufacturer Part Number: AD5280BRU20
• Description: IC DGTL POT 20K 256POS 14-TSSOP
• Manufacturer: Analog Devices Inc

Specifications of AD5280BRU20

• Rohs Status: RoHS non-compliant
• Taps: 256
• Resistance (ohms): 20K
• Number Of Circuits: 1
• Temperature Coefficient: 30 ppm/°C Typical
• Memory Type: Volatile
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 4.5 V ~ 16.5 V, ±4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 14-TSSOP
• Resistance In Ohms: 20K

input voltage applied to Terminal A and Terminal B is
For a more accurate calculation that includes the effect of wiper
resistance, V
Table 6. Serial Format of Data Accepted from the I
S
where:
Abbreviation
S
P
A
X
AD1, AD0
R/W
A/B
RS
SD
O , O
D7, D6, D5, D4, D3, D2, D1, D0
2
START BY
MASTER
0
SDA
V
V
1
SCL
W
W
1
( )
( )
D
D
0
=
=
W
Slave Address Byte
can be found as
256
R
D
1 1
WB
0
R
1
AB
V
( )
D
A
START BY
1
MASTER
+
SLAVE ADDRESS BYTE
AD1
V
SDA
SCL
256 −
A
0
256
+
FRAME 1
R
1
WA
AD
0
D
R
AB
V
( )
D
B
1 AD1
1
Figure 46. Reading Data from a Previously Selected RDAC Register in Write Mode
0
Midscale reset, active high (only affects selected channel)
Equals
Start condition
Stop condition
Acknowledge
Don’t care
Package pin programmable address bits
Read enable at high and write enable at low
RDAC subaddress select; 0 = RDAC1 and 1 = RDAC2
Shutdown; same as SHDN pin operation except inverse logic (only affects selected channel)
Output logic pin latched values; default Logic 0
Data bits
V
R/
W
B
1
AD0
SLAVE ADDRESS BYTE
0
A
R/W
AD5280/5282
FRAME 1
ACK. BY
A /B
1
9
1
Figure 45. Writing to the RDAC Register
A/B
2
RS
C Bus
AD1 AD0 R/W
1
Instruction Byte
RS
S
D
Rev. C | Page 15 of 28
(3)
(4)
INSTRUCTION BYTE
SD
AD5280/AD5282
O
FRAME 2
ACK. BY
1
O1
9
O
O2
DATA BYTE FROM PREVIOUSLY SELECTED
2
D7
Operation of the digital potentiometer in divider mode results
in a more accurate operation over temperature. Unlike rheostat
mode, the output voltage is dependent mainly on the ratio of
the internal resistors R
values; therefore, the temperature drift reduces to 5 ppm/°C.
1
X
X X X
D6
X
D5
AD5280/AD5282
X
FRAME 2
ACK. BY
D4
A
9
D3
D7
D7
1
D2
D6
D6
WA
D1
and R
D5
D0
NO ACK. BY
DATA BYTE
D
5
FRAME 3
MASTER
D4
9
WB
A
9
Data Byte
STOP BY
MASTER
D
4
D3
and not on the absolute
D2
AD5280/AD5282
D
3
D1
D
2
AD5280/5282
D0
ACK. BY
D
1
STOP BY
MASTER
D
0
A
P