Datasheet

MCP4021/2/3/4
DS21945E-page 46 © 2006 Microchip Technology Inc.
6.3.2 MONOTONIC OPERATION
Monotonic operation means that the device’s
resistance increases with every step change (from
terminal A to terminal B or terminal B to terminal A).
The wiper resistance is different at each tap location.
When changing from one tap position to the next (either
increasing or decreasing), the ΔR
W
is less than the
ΔR
S
. When this change occurs, the device voltage and
temperature are “the same” for the two tap positions.
FIGURE 6-7: Resistance, R
BW
.
0x3F
0x3E
0x3D
0x03
0x02
0x01
0x00
Digital Input Code
Resistance (R
BW
)
R
W
(@ tap)
R
S0
R
S1
R
S3
R
S62
R
S63
R
BW
= R
Sn
+ R
W(@ Tap n
)
n = 0
n = ?