MCP3551 Datasheet, PDF (1/30 Pages) Microchip Technology – Low-Power, Single-Channel 22-Bit Delta-Sigma ADCs

MCP3551/3
Low-Power, Single-Channel 22-Bit Delta-Sigma ADCs
Features
• 22-bit ADC in Small 8-pin MSOP Package with
Automatic Internal Offset and Gain Calibration
• Low-Output Noise of 2.5 µV_RMS with Effective
Resolution of 21.9 bits (MCP3551)
• 3 µV Typical Offset Error
• 2 ppm Typical Full-Scale Error
• 6 ppm Maximum INL Error
• Total Unadjusted Error Less Than 10 ppm
• No Digital Filter Settling Time, Single-Command
Conversions through 3-wire SPI^™ Interface
• Ultra-Low Conversion Current (MCP3551):
- 100 µA typical (V_DD = 2.7V)
- 120 µA typical (V_DD = 5.0V)
• Differential Input with V_SS to V_DD Common Mode
Range
• 2.7V to 5.5V Single-Supply Operation
• Extended Temperature Range:
- -40°C to +125°C
Applications
• Weigh Scales
• Direct Temperature Measurement
• 6-digit DVMs
• Instrumentation
• Data Acquisition
• Strain Gauge Measurement
Block Diagram
V_REF
V_SS V_DD
V_IN+
V_IN-
3rd-Order
ΔΣ ADC
Modulator
w/ Internal
Calibration
Internal
Oscillator
V_DD
POR
SCK
SDO
RDY
CS
Description
The Microchip Technology Inc. MCP3551/3 devices
are 2.7V to 5.5V low-power, 22-bit Delta-Sigma
Analog-to-Digital Converters (ADCs). The devices offer
output noise as low as 2.5 µV_RMS, with a total
unadjusted error of 10 ppm. The family exhibits 6 ppm
Integral Non-Linearity (INL) error, 3 µV offset error and
less than 2 ppm full-scale error. The MCP3551/3
devices provide high accuracy and low noise
performance for applications where sensor
measurements (such as pressure, temperature and
humidity) are performed. With the internal oscillator
and high oversampling rate, minimal external
components are required for high-accuracy
applications.
This product line has fully differential analog inputs,
making it compatible with a wide variety of sensor,
industrial control or process control applications.
The MCP3551/3 devices operate from -40°C to +125°C
and are available in the space-saving 8-pin MSOP and
SOIC packages.
Package Types:
MCP3551/3
SOIC, MSOP
V_REF 1
V_IN+ 2
V_IN– 3
V_SS 4
8 V_DD
7 CS
6 SDO/RDY
5 SCK
Device Selection Table
Part
Number
Sample
Rate
Effective
Resolution
MCP3551 13.75 sps
21.9 bits
MCP3553
60 sps
20.6 bits
50/60 Hz
Rejection
50/60 Hz
(simultaneous)
N/A
© 2005 Microchip Technology Inc.
DS21950B-page 1