MCP4461T-502E/ML Microchip Technology, MCP4461T-502E/ML Datasheet - Page 95

• Manufacturer Part Number: MCP4461T-502E/ML
• Description: IC DGTL POT 257TAPS 5K 20QFN
• Manufacturer: Microchip Technology

Specifications of MCP4461T-502E/ML

• Package / Case: 20-VFQFN Exposed Pad
• Temperature Coefficient: 150 ppm/°C Typical
• Taps: 257
• Resistance (ohms): 5K
• Number Of Circuits: 4
• Memory Type: Non-Volatile
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Number Of Pots: Quad
• Taps Per Pot: 257
• Resistance: 5 KOhms
• Wiper Memory: Non Volatile
• Buffered Wiper: Buffered
• Digital Interface: I2C
• Operating Supply Voltage: 2.7 V to 5.5 V
• Supply Current: 600 uA
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Description/function: Quad I2C Digital POT with Nonvolatile Memory
• Mounting Style: SMD/SMT
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.7 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

B.2
The low-voltage nonlinear characteristics can be
minimized by application design. The section will show
two application circuits that can be used to control a
programmable reference voltage (V
Minimizing the low-voltage nonlinear characteristics is
done by keeping the voltages on the wiper switch
nodes at a voltage where either the NMOS or PMOS
transistor is turned on.
An example of this is if we are using a digital
potentiometer for a voltage reference (V
that we want V
In example implementation #1
window the digital potentiometer using resistors R1 and
R2. When the wiper code is at full scale, the V
voltage will be ≥ 0.6 * V
at zero scale the V
Remember that the digital potentiometers R
must be included.
voltage can be selected to be between 0.455 * V
0.727 * V
respect to the voltages on the resistor network node, at
1.8V the V
while the V
These voltages cause the wiper resistance to be in the
nonlinear region (see
mode, the variation of the wiper resistance is typically
not an issue, as shown by the INL/DNL graph
(Figure
In example implementation #2
the digital potentiometer in Rheostat mode. The
resistor ladder uses resistors R1 and R2 with R
the bottom of the ladder. When the wiper code is at full
scale, the V
the wiper code is at full scale the V
≤ 0.5 * V
R
the V
V
range. With respect to the voltages on the resistor
network node, at 1.8V the V
0.29V to 0.38V. These voltages cause the wiper
resistance to be in the linear region (see
© 2010 Microchip Technology Inc.
DD
AB
variation must be included.
OUT
and 0.687 * V
2-7).
DD
Optimizing Circuit Design for
Low-Voltage Characteristics
voltage can be selected to be between 0.50 *
DD
A
B
. Remember that the digital potentiometers
OUT
, which includes the desired range. With
voltage would range from 1.29V to 1.31V
voltage would range from 0.82V to 0.86V.
OUT
voltage will be ≥ 0.6 * V
to range from 0.5 * V
OUT
Table B-1
DD
DD,
Figure
, which includes the desired
voltage will be ≤ 0.5 * V
and when the wiper code is
W
voltage would range from
B-12). In Potentiometer
shows that the V
(Figure
Table B-2
OUT
OUT
(Figure
DD
).
OUT
voltage will be
B-16) we use
Figure
DD
to 0.6 * V
AB
B-15), we
shows that
). Let’s say
and when
variation
DD
B-12).
BW
OUT
OUT
and
DD
DD
at
.
.
FIGURE B-15:
TABLE B-1:
R1
R2
R
V
V
V
V
Legend: FS – Full Scale, ZS – Zero Scale
A
OUT
OUT
B
AB
(@ FS) 0.714 V
(@ ZS) 0.476 V
R2
R1
MCP444X/446X
A
B
0.714 V
0.476 V
12,000
20,000
EXAMPLE #1 VOLTAGE
CALCULATIONS
8,000
V
V
Min
B
A
Example Implementation #1.
W
DD
DD
DD
DD
V
Variation
0.70 V
0.50 V
0.70 V
0.50 V
W
12,000
20,000
10,000
Typ
V
DD
DD
DD
DD
DS22265A-page 95
OUT
0.727 V
0.455 V
0.727 V
0.455 V
12,000
20,000
12,000
Max
DD
DD
DD
DD