AD5259BRMZ100 Analog Devices Inc, AD5259BRMZ100 Datasheet - Page 20

• Manufacturer Part Number: AD5259BRMZ100
• Description: IC DGTL POT 100K 256POS 10-MSOP
• Manufacturer: Analog Devices Inc

Specifications of AD5259BRMZ100

• Taps: 256
• Resistance (ohms): 100K
• Number Of Circuits: 1
• Temperature Coefficient: 500 ppm/°C Typical
• Memory Type: Non-Volatile
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 2.7 V ~ 3.3 V, 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 10-MSOP, Micro10™, 10-uMAX, 10-uSOP
• Resistance In Ohms: 100K
• End To End Resistance: 100kohm
• Track Taper: Linear
• Resistance Tolerance: ± 30%
• No. Of Steps: 256
• Supply Voltage Range: 2.7V To 5.5V
• Control Interface: I2C, Serial
• No. Of Pots: Single
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AD5259EVAL - BOARD EVAL FOR AD5259 DGTL POT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

AD5259
DISPLAY APPLICATIONS
CIRCUITRY
A special feature of the AD5259 is its unique separation of the
V
flexibility in applications that do not always provide needed
supply voltages.
In particular, LCD panels often require a V
range of 3 V to 5 V. The circuit in Figure 46 is the rare excep-
tion in which a 5 V supply is available to power the digital
potentiometer.
1F
In the more common case shown in Figure 47, only analog 14.4 V
and digital logic 3.3 V supplies are available. By placing discrete
resistors above and below the digital potentiometer, V
now be tapped off the resistor string itself. Based on the chosen
resistor values, the voltage at V
allowing the wiper to be safely operated all the way up to 4.8 V.
The current draw of V
it is only on the order of microamps. V
3.3 V digital supply because V
is needed when writing to the EEPROM. It would be imprac-
tical to try and source 35 mA through the 70 kΩ resistor,
therefore, V
C1
LOGIC
VCC (~3.3V)
MCU
and V
10k
R6
LOGIC
DD
10k
R5
supply pins. The separation provides greater
Figure 46. V
is not connected to the same node as V
5V
AD5259
DD
V
V
SCL
SDA
GND
DD
LOGIC
will not affect that node’s bias because
COM
14.4V
A
B
Adjustment Application
LOGIC
R1
70k
R2
10k
R3
25k
DD
W
in this case equals 4.8 V,
will draw the 35 mA which
LOGIC
–
+
AD8565
U1
COM
is tied to the MCU’s
voltage in the
3.5V < V
DD
COM
DD
can
.
< 4.5V
Rev. B | Page 20 of 24
For this reason, V
supply pins that can either be tied together or treated inde-
pendently; V
and V
flexibility.
1F
For a more detailed look at this application, refer to the article,
“Simple VCOM Adjustment uses any Logic Supply Voltage” in
the September 30, 2004 issue of EDN magazine.
C1
VCC (~3.3V)
Figure 47. Circuitry When a Separate Supply is Not Available for V
MCU
DD
10k
biasing up the A, B, and W terminals for added
R6
SUPPLIES POWER
TO BOTH THE
MICRO AND THE
LOGIC SUPPLY OF
THE DIGITAL POT
LOGIC
10k
R5
LOGIC
supplying the logic/EEPROM with power,
AD5259
and V
V
V
SCL
SDA
GND
DD
LOGIC
14.4V
DD
A
B
R1
70k
R2
10k
R3
25k
are provided as two separate
W
–
+
AD8565
U1
3.5V < V
COM
DD
< 4.5V