MCP4021-202E/SN Microchip Technology, MCP4021-202E/SN Datasheet - Page 43

• Manufacturer Part Number: MCP4021-202E/SN
• Description: IC DGTL POT 2.1K 1CH 8SOIC
• Manufacturer: Microchip Technology

Specifications of MCP4021-202E/SN

• Memory Type: Non-Volatile
• Taps: 64
• Resistance (ohms): 2.1K
• Number Of Circuits: 1
• Temperature Coefficient: 150 ppm/°C Typical
• Interface: Up/Down
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Resistance In Ohms: 2.10K
• End To End Resistance: 2.1kohm
• Resistance Tolerance: ± 20%
• No. Of Steps: 64
• Supply Voltage Range: 2.7V To 5.5V
• Control Interface: Serial
• No. Of Pots: Single
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: MCP4XXXDM-DB - BOARD DAUGHTER DIGIPOT MCP4XXXMCP402XEV - BOARD EVAL FOR MCP402X
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

6.1
6.1.1
When used as a rheostat, two of the three digital
potentiometer’s terminals are used as a resistive
element in the circuit. With terminal W (wiper) and
either terminal A or terminal B, a variable resistor is
created. The resistance will depend on the tap setting
of the wiper and the wiper’s resistance. The resistance
is controlled by changing the wiper setting.
The unused terminal (B or A) should be left floating.
Figure 6-2
used. Reversing the polarity of the A and B terminals
will not affect operation.
FIGURE 6-2:
This allows the control of the total resistance between
the two nodes. The total resistance depends on the
“starting” terminal to the wiper terminal. At the code
00h, the R
resistance in maximized (R
code 3Fh, the R
R
The resistance step size (R
resistor.
The change in wiper-to-end terminal resistance over
temperature is shown in
Figure 2-27
temperature will occur in the first few codes due to the
wiper
resistance. The remaining codes are dominated by the
total resistance tempco R
© 2006 Microchip Technology Inc.
BW
Note:
A
resistance in maximized (R
B
resistance
Resistor Configurations
BW
shows the two possible resistors that can be
RHEOSTAT CONFIGURATION
To avoid damage to the internal wiper
circuitry in this configuration, care should
be taken to insure the current flow never
exceeds 2.5 mA.
and
resistance is minimal (R
AW
Figure
W
resistance is minimal (R
coefficient
Rheostat Configuration.
2-37. The most variation over
AB
AB
S
) equates to one LSb of the
.
Figure
+ R
AB
W
affecting
). Conversely, at the
R
+ R
Resistor
2-6,
AW
W
W
), but the R
).
or
Figure
W
the
), but the
R
BW
2-17,
total
AW
6.1.2
When used as a potentiometer, all three terminals are
tied to different nodes in the circuit. This allows the
potentiometer to output a voltage proportional to the
input voltage. This configuration is sometimes called
voltage divider mode. The potentiometer is used to
provide a variable voltage by adjusting the wiper
position between the two endpoints as shown in
Figure
terminals will not affect operation.
FIGURE 6-3:
The temperature coefficient of the R
minimal by design. In this configuration, the resistors all
change uniformally, so minimal variation should be
seen.
The wiper resistor temperature coefficient is different
from the R
node V
resistance, just the ratio of the R
temperature coefficient in most cases can be
ignored.
Note:
6-3. Reversing the polarity of the A and B
3
(Figure
AB
POTENTIOMETER
CONFIGURATION
To avoid damage to the internal wiper
circuitry in this configuration, care should
be taken to insure the current flow never
exceeds 2.5 mA.
temperature coefficient. The voltage at
MCP4021/2/3/4
6-3) is not dependent on this wiper
A
B
Potentiometer Configuration.
V
V
2
1
W
AB
DS21945E-page 43
resistors, so this
V
AB
3
resistors is