CAT5122SDI-10-T ON Semiconductor, CAT5122SDI-10-T Datasheet - Page 8

• Manufacturer Part Number: CAT5122SDI-10-T
• Manufacturer: ON Semiconductor

Specifications of CAT5122SDI-10-T

• Number Of Elements: 1
• # Of Taps: 16
• Resistance (max): 10KOhm
• Power Supply Requirement: Single
• Interface Type: Serial (2-Wire)
• Single Supply Voltage (typ): 3.3/5V
• Dual Supply Voltage (typ): Not RequiredV
• Single Supply Voltage (min): 2.7V
• Single Supply Voltage (max): 5.5V
• Dual Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 5
• Lead Free Status / RoHS Status: Compliant

CAT5120/5121/5122
Doc. No. 2121, Rev. B
APPLICATIONS INFORMATION
The Minipots are intended for circuits requiring digitally
controlled adjustable resistance, such as LCD contrast
control, where voltage biasing adjusts the display con-
trast.
Alternative Positive LCD Bias Control
Use an op amp to provide buffering and gain on the
output of the CAT5120. Connect the mechanical
potentiometer to the positive input of a noninverting op
amp (Figure 3) to select a portion of the input signal by
digitally controlling the wiper terminal. Figure 4 shows a
similar circuit for the CAT5121.
Figure 3. Positive LCD Bias Control
Figure 5a. Adjustable Gain Circuit
CAT5120
+5V
L
H
W
V
IN
H
L
CAT5121
V
CC
30V
V
OUT
V
OUT
8
Figure 4. Positive LCD Bias Control
Figure 5b. Adjustable Gain Circuit
Adjustable Gain
Figure 5 shows how to use the variable resistor to
digitally adjust the gain of a noninverting op amp
configuration. Connect the CAT5121 in series with a
resistor to ground to form the adjustable gain control of
a noninverting amplifier. The Minipots have a low 5ppm/
˚C ratiometric tempco that allows for a very stable
adjustable gain configuration over temperature.
CAT5121
L
V
IN
+5V
W
CAT5120
H
L
H
V
CC
Characteristics subject to change without notice
© 2005 by Catalyst Semiconductor, Inc.
30V
V
OUT
V
OUT