MCP3422/3/4
18-Bit, Multi-Channel Analog-to-Digital Converter with
2
I C Interface and On-Board Reference
Features Description
18-bit ADC with Differential Inputs: The MCP3422, MCP3423 and MCP3424 devices
(MCP3422/3/4) are the low noise and high accuracy
- 2 channels: MCP3422 and MCP3423
18-Bit delta-sigma analog-to-digital ( A/D) converter
- 4 channels: MCP3424
family members of the MCP342X series from Microchip
Differential Input Full Scale Range: -V to
REF
Technology Inc. These devices can convert analog
+V
REF
inputs to digital codes with up to 18 bits of resolution.
Self Calibration of Internal Offset and Gain per
The on-board 2.048V reference voltage enables an
Each Conversion
input range of 2.048V differentially (full scale
On-Board Voltage Reference (V ):
REF
range = 4.096V/PGA).
- Accuracy: 2.048V 0.05%
These devices can output analog-to-digital conversion
- Drift: 15 ppm/C
results at rates of 3.75, 15, 60, or 240 samples per
On-Board Programmable Gain Amplifier (PGA):
second depending on the user controllable
2
- Gains of 1, 2, 4 or 8
configuration bit settings using the two-wire I C serial
interface. During each conversion, the device
INL: 10 ppm of Full Scale Range
calibrates offset and gain errors automatically. This
Programmable Data Rate Options:
provides accurate conversion results from conversion
- 3.75 SPS (18 bits)
to conversion over variations in temperature and power
- 15 SPS (16 bits)
supply fluctuation.
- 60 SPS (14 bits)
The user can select the PGA gain of x1, x2, x4, or x8
- 240 SPS (12 bits)
before the analog-to-digital conversion takes place.
One-Shot or Continuous Conversion Options
This allows the MCP3422/3/4 devices to convert a very
Low Current Consumption: weak input signal with high resolution.
- 135 A typical
The MCP3422/3/4 devices have two conversion
(V = 3V, Continuous Conversion)
DD modes: (a) One-Shot Conversion mode and (b)
- 36 A typical Continuous Conversion mode. In One-Shot conversion
(V = 3V, One-Shot Conversion with 1 SPS) mode, the device performs a single conversion and
DD
enters a low current standby mode automatically until it
On-Board Oscillator
2 receives another conversion command. This reduces
I C Interface:
current consumption greatly during idle periods. In
- Standard, Fast and High Speed Modes
Continuous conversion mode, the conversion takes
- User configurable two external address pins
place continuously at the set conversion speed. The
for MCP3423 and MCP3424
device updates its output buffer with the most recent
Single Supply Operation: 2.7V to 5.5V
conversion data.
Extended Temperature Range: -40C to +125C
The devices operate from a single 2.7V to 5.5V power
2
supply and have a two-wire I C compatible serial
Typical Applications
interface for a standard (100 kHz), fast (400 kHz), or
high-speed (3.4 MHz) mode.
Portable Instrumentation and Consumer Goods
2
The I C address bits for the MCP3423 and MCP3424
Temperature Sensing with RTD, Thermistor, and
2
are selected by using two external I C address
Thermocouple
selection pins (Adr0 and Adr1). The user can configure
Bridge Sensing for Pressure, Strain, and Force
the device to one of eight available addresses by
Weigh Scales
connecting these two address selection pins to V ,
DD
2
Battery Fuel Gauges
V or float. The I C address bits of the MCP3422 are
SS
programmed at the factory during production.
Factory Automation Equipment
2009 Microchip Technology Inc. DS22088C-page 1MCP3424
MCP3423
MCP3422
MCP3422/3/4
The MCP3422 and MCP3423 devices have two The MCP3422 is available in 8-pin SOIC, DFN, and
differential input channels and the MCP3424 has four- MSOP packages. The MCP3423 is available in 10-pin
differential input channels. All electrical properties of DFN, and MSOP packages. The MCP3424 is available
in 14-pin SOIC and TSSOP packages.
these three devices are the same except the
2
differences in the number of input channels and I C
address bit selection options.
Package Types
MCP3424
MCP3422 MCP3423
SOIC, TSSOP
MSOP, SOIC MSOP
CH1+ 1 14
CH1+ CH4-
CH1+ 10 Adr1
8 CH2- 1
1
CH1-
CH1- 2 13
CH1- 2 9 Adr0 CH4+
7
2 CH2+
V 3 SCL 12
V 8 3
3 6 V SS CH2+ CH3-
DD
SS
CH2+ 4
7 SDA
4 5 SCL
SDA
CH2- 4 11
CH3+
V
CH2- 5 6
DD
5
V 10
Adr1
SS
6
9
V
Adr0
DD
MCP3422
MCP3423
7 8
SDA SCL
2x3 DFN*
3x3 DFN*
CH1+ 1 8 CH2-
CH1+ 1 10 Adr1
CH1- 2 7 CH2+
EP CH1- 2 9 Adr0
EP
9
V 3 6 V
V 3 8 SCL
DD SS SS
11
SDA 4 5 SCL CH2+ SDA
4 7
CH2- 5 6 V
DD
* Includes Exposed Thermal Pad (EP); see Table 3-1.
Functional Block Diagram
V
V
DD
SS
MCP3422
Voltage Reference
(2.048V)
V
REF
CH1+
SCL
2
I C
ADC
CH1-
PGA
Converter SDA
Interface
CH2+
Gain = 1,2,4, or 8
CH2-
Clock
Oscillator
DS22088C-page 2 2009 Microchip Technology Inc.
MUX