LMP90077 Datasheet, PDF (1/64 Pages) Texas Instruments – Multi-Channel, Low-Power 16-Bit Sensor AFE with True Continuous Background Calibration

LMP90077, LMP90078, LMP90079, LMP90080
www.ti.com
SNAS521F – JULY 2011 – REVISED MARCH 2013
LMP90080/LMP90079/LMP90078/LMP90077 Sensor AFE System: Multi-Channel, Low-
Power 16-Bit Sensor AFE with True Continuous Background Calibration
Check for Samples: LMP90077, LMP90078, LMP90079, LMP90080
FEATURES
1
•23 16-Bit Low-Power Sigma Delta ADC
• True Continuous Background Calibration at All
Gains
• In-Place System Calibration Using Expected
Value Programming
• Low-Noise Programmable Gain (1x - 128x)
• Continuous Background Open/Short and Out
of Range Sensor Diagnostics
• 8 Output Data Rates (ODR) with Single-Cycle
Settling
• 2 Matched Excitation Current Sources from
100 µA to 1000 µA (LMP90080/LMP90078)
• 4-DIFF / 7-SE Inputs (LMP90080/LMP90079)
• 2-DIFF / 4-SE Inputs (LMP90078/LMP90077)
• 7 General Purpose Input/Output Pins
• Chopper-Stabilized Buffer for Low Offset
• SPI 4/3-Wire with CRC Data Link Error
Detection
• 50 Hz to 60 Hz Line Rejection at ODR ≤13.42
SPS
• Independent Gain and ODR Selection per
Channel
• Supported by WEBENCH^® Sensor AFE
Designer
• Automatic Channel Sequencer
KEY SPECIFICATIONS
• ENOB/NFR: Up to 16/16 Bits
• Offset Error (typ): 8.4 nV
• Gain Error (typ): 7 ppm
• Total Noise: <10 µV-rms
• Integral Non-Linearity (INL Max): ±1 LSB
• Output Data Rates (ODR): 1.6775 - 214.65 SPS
• Analog Voltage, V_A: +2.85 to +5.5 V
• Operating Temp Range: -40 to 125°C
• Package: 28 Pin Exposed Pad
APPLICATIONS
• Temperature and Pressure Transmitters
• Strain Gauge Interface
• Industrial Process Control
DESCRIPTION
The LMP90080/LMP90079/LMP90078/LMP90077 are
highly integrated, multi-channel, low-power 16-bit
Sensor AFEs. The devices feature a precision, 16-bit
Sigma Delta Analog-to-Digital Converter (ADC) with a
low-noise programmable gain amplifier and a fully
differential high impedance analog input multiplexer.
A true continuous background calibration feature
allows calibration at all gains and output data rates
without interrupting the signal path. The background
calibration feature essentially eliminates gain and
offset errors across temperature and time, providing
measurement accuracy without sacrificing speed and
power consumption.
Another feature of the LMP90080/LMP90079
/LMP90078/LMP90077 is continuous background
sensor diagnostics, allowing the detection of open
and short circuit conditions and out-of-range signals,
without requiring user intervention, resulting in
enhanced system reliability.
Two sets of independent external reference voltage
pins allow multiple ratiometric measurements. In
addition, two matched programmable current sources
are available in the LMP90080/LMP90078 to excite
external sensors such as resistive temperature
detectors and bridge sensors. Furthermore, seven
GPIO pins are provided for interfacing to external
LEDs and switches to simplify control across an
isolation barrier.
Collectively, these features make the LMP90080
/LMP90079/LMP90078/LMP90077 complete analog
front-ends for low-power, precision sensor
applications such as temperature, pressure, strain
gauge, and industrial process control. The
LMP90080/LMP90079/LMP90078/LMP90077 are
ensured over the extended temperature range of -
40°C to +125°C and are available in a 28-pin
package with an exposed pad.
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
WEBENCH is a registered trademark of Texas Instruments.
2
All other trademarks are the property of their respective owners.
3
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2011–2013, Texas Instruments Incorporated