X9313 Datasheet, PDF (9/11 Pages) Xicor Inc. – E2POT™ Nonvolatile Digital Potentiometer

X9313
Applications Information
Electronic digitally controlled potentiometers (XDCP) 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
V_R
V_R
V_H
V_W/R_W
V_L
THREE-TERMINAL POTENTIOMETER;
VARIABLE VOLTAGE DIVIDER
Basic Circuits
BUFFERED REFERENCE VOLTAGE
R₁
+V
V_REF
+5V
V_W
OP-07
+
V_OUT
–
-5V
V_OUT = V_W/R_W
I
TWO-TERMINAL VARIABLE RESISTOR;
VARIABLE CURRENT
CASCADING TECHNIQUES
+V
+V
X
V_W/R_W
+V
V_W
(a)
(b)
NONINVERTING AMPLIFIER
+5V
V_S
+
LM308A
V_O
–
-5V
R₂
R₁
V_O = (1 + R₂ / R₁)V_S
VOLTAGE REGULATOR
OFFSET VOLTAGE ADJUSTMENT
COMPARATOR WITH HYSTERESIS
V_IN
317
V_O (REG)
R₁
I_adj
R₂
V_O (REG) = 1.25V (1 + R₂ / R₁) + I_ADJ R₂
R₁
V_S
100kΩ
10kΩ
R₂
–
+
TL072
10kΩ
10kΩ
+12V
-12V
V_S ^LT311A –
V_O
+
V_O
R₁ R₂
V_UL = [R₁ / (R₁ + R₂)] V_O(max)
V_LL = [R₁ / (R₁ + R₂)] V_O(min)
(for additional circuits see AN115)
9
FN8177.2
September 9, 2005