MCP4921-E/SN Microchip Technology, MCP4921-E/SN Datasheet - Page 31

• Manufacturer Part Number: MCP4921-E/SN
• Description: IC DAC 12BIT SNGL W/SPI 8SOIC
• Manufacturer: Microchip Technology

Specifications of MCP4921-E/SN

• Number Of Converters: 1
• Package / Case: 8-SOIC (3.9mm Width)
• Settling Time: 4.5µs
• Number Of Bits: 12
• Data Interface: Serial, SPI™
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Resolution: 12 bit
• Interface Type: Serial (3-Wire, SPI, Microwire)
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.7 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Package: 8SOIC N
• Architecture: Resistor-String
• Digital Interface Type: Serial (3-Wire, SPI, Microwire)
• Number Of Outputs Per Chip: 1
• Output Type: Voltage
• Full Scale Error: 1 %FSR
• Integral Nonlinearity Error: ±12 LSB
• Maximum Settling Time: 4.5(Typ) us
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power Dissipation (max): -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

6.6
In some applications, precision digital control of the
output range is desirable.
to use the DAC devices to achieve this in a bipolar or
single-supply application.
EXAMPLE 6-4:
 2010 Microchip Technology Inc.
Thevenin
Equivalent
V
V
V
V
IN+
O
OUTB
OUTA
Selectable Gain and Offset Bipolar
Voltage Output Using DAC
Devices
=
=
Offset Adjust Gain Adjust
V
V
----------------------------------------------- -
IN+
=
=
OUTB




V
V
1
REFB
REFA
V
R
+
R
V
IN+
3
R
----- -
R
4
45
+
2
1
V
+
BIPOLAR VOLTAGE SOURCE WITH SELECTABLE GAIN AND OFFSET.
V
G


G
R
REFB
=
SPI
=
REFA
V
B
–
4
A

CC-

V
---------------------------------------------- -
Example 6-4
V
V
------------------------------------------- -
D
------ -
D
------ -
2
2
OUTB
OUTA
CC+
N
N
B
A
R
3
3
V
V
R
R
R
DAC
DAC
DD
DD
4
3


4
R
R
----- -
R
+
+
45
+
2
1
R
R


V
+
A
B
Bipolar “Window” DAC using R
5
45
CC-
DAC
V
illustrates how
45
DAC
R
R
5
A
3
V
V
(Gain Adjust)
B
OUTA
OUTB
(Offset Adjust)
D
R
A
V
45
, D
O
G
R
R
N = DAC Bit Resolution
1
3
X
=
=
B
= Gain selection (1x or 2x)
Offset Adjust Gain Adjust
= Digital value of DAC (0-255) for MCP4901/MCP4902
= Digital value of DAC (0-4095) for MCP4912/MCP4922
= Digital value of DAC (0-1023) for MCP4911/MCP4912
------------------
R
V
R
4
IN+
4
+
R
V
V


R
5
1
This circuit is typically used in Multiplier mode and is
ideal for linearizing a sensor whose slope and offset
varies. Refer to Section 6.9 “Using Multiplier Mode”
for more information on Multiplier mode.
The equation to design a bipolar “window” DAC would
be utilized if R
CC
CC
5
+
R
MCP4901/4911/4921
+
R
–
R
----- -
R
4
5
2
1


–
0.1uF
4
V
and R
OUTA
3
, R


5
R
----- -
R
4
2
1


and R
V
V
CC
R
CC
2
+
–
5
are populated.
DS22248A-page 31
V
O