X9421 Xicor, X9421 Datasheet - Page 18

• Manufacturer Part Number: X9421
• Description: Single Digitally Controlled (XDCP) Potentiometer
• Manufacturer: Xicor

X9421
APPLICATIONS INFORMATION
Electronic potentiometers provide three powerful application advantages: (1) the variability and reliability of a solid-
state potentiometer, (2) the flexibility of computer-based digital controls, and (3) the retentivity of nonvolatile
memory used for the storage of multiple potentiometer settings or data.
Basic Configurations of Electronic Potentiometers
Basic Circuits
REV 1.1.6 8/1/02
V
+V
IN
V
O
(REG) = 1.25V (1+R
Buffered Reference Voltage
R
V
Voltage Regulator
1
W
I
adj
317
R
Three terminal Potentiometer;
V
2
W
Variable voltage divider
2
/R
1
R
)+I
+
–
1
V
V
adj
+5V
–5V
H
L
V
R
OP-07
R
2
V
O
V
(REG)
OUT
V
W
= V
+12V
W
V
Offset Voltage Adjustment
10K
S
www.xicor.com
10K
Cascading Techniques
+V
+V
100K
-12V
(a)
R
1
10K
V
W
–
+
TL072
+V
R
2
(b)
Two terminal Variable Resistor;
X
V
W
Variable current
Characteristics subject to change without notice.
V
O
V
V
V
V
UL
LL
R
Comparator with Hysterisis
V
S
S
= {R
V
= {R
Noninverting Amplifier
O
I
= (1+R
1
1
/CR
R
/CR
1
R
1
1
+R
1
2
+R
+
–
/R
+5V
–5V
R
2
2
1
–
+
2
} V
} V
)V
O
S
O
LM308A
(min)
(max)
R
2
18 of 21
V
O
V
O