MCP402XEV Microchip Technology, MCP402XEV Datasheet - Page 20

• Manufacturer Part Number: MCP402XEV
• Description: BOARD EVAL FOR MCP402X
• Manufacturer: Microchip Technology

Specifications of MCP402XEV

• Main Purpose: Digital Potentiometer
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: MCP4021
• Primary Attributes: 1 Single Pot, 10 kOhm, 64 Tap, Non Volatile
• Secondary Attributes: 2.7 ~ 5.5 V, 150 ppm/°C
• Processor To Be Evaluated: MCP402X
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

MCP401X/2X Evaluation Board User’s Guide
DS51546B-page 16
2.3.4
Table 2-3 shows the relation between the wiper position and the voltage on the wiper
when 5.0 volts is applied to the MCP402X Digital Potentiometer Evaluation Board
where the resistors R2 and R3 are 2500
10 k . Equation 2-4 shows the formula for these calculations.
EQUATION 2-4:
The typical step resistance for the 10 k
5V supply and a 15 k total resistance (2.5 k + 2.5 k
step is approximately 0.053V.
TABLE 2-3:
Position
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
Note 1:
(1)
Wiper
2:
Voltage
Wiper Voltages
0.833
0.866
0.939
0.992
1.045
1.098
1.151
1.204
1.257
1.310
1.362
1.415
1.468
1.521
1.574
1.627
(V)
Voltage at Wiper
This is zero-scale, wiper is connected to terminal B.
This is full-scale, wiper is connected to terminal A.
WIPER POSITION AND CORRESPONDING VOLTAGE
CALCULATING THE VOLTAGE ON THE MCP402X DIGITAL
POTENTIOMETER EVALUATION BOARD
Position
Where:
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
=
Wiper
System V
System V
Voltage
1.680
1.733
1.786
1.839
1.892
1.944
1.997
2.050
2.103
2.156
2.209
2.262
2.315
2.368
2.421
2.474
(V)
DD
R
R2
R3
DD
AB
MCP4021 is approximately 158.73 . With a
-----------------------------------------------------------------------------------------
and the MCP4011 resistor value (R
R3
=
=
=
=
+
Position
5.0V
2.5 k
2.5 k
10 k
Wiper Position
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
R3
Wiper
+
Voltage
R
2.526
2.579
2.632
2.685
2.738
2.791
2.844
2.897
2.950
3.003
3.056
3.108
3.161
3.214
3.267
3.320
AB
10 k ), the delta voltage per
(V)
© 2005 Microchip Technology Inc.
+
R2
R
AB
Position
63
63
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
(2)
Wiper
Voltage
3.373
3.426
3.479
3.532
3.585
3.638
3.690
3.743
3.796
3.849
3.902
3.955
4.008
4.061
4.114
4.167
AB
(V)
) is