Pressure Transmitter Solutions PDF

Pressure Transmitter Solutions PDF
Project Code: APM-Pressure-Transmitter-2013
ADI Pressure Transmitter Solutions
Industrial Pressure Transmitter System Theory and Typical Architecture
A pressure transmitter can measure flow rate, pressure, level, and so on. Principles of a pressure sensor used in it, which are the piezoresistance effect type,
the capacitance type, and the micro resonator type, are diverse. Diaphragms of a single silicon crystal are used as pressure receiving elements in each type.
With a multiple piezoresistive gauge sensor for application to intelligent pressure transmitter, it can measure three quantities (i.e., differential and static
pressure and the temperature).
In general, a pressure transmitter could be powered by a battery, a line power, or a loop power and consist of power supplies, pressure/temperature sensors,
signal conditioning, ADC, processors, display, keyboard, logic I/Os, and multiple communications like 4 mA to 20 mA, HART, RS-485/RS-422/RS-232,
PROFIBUS, Modbus, and foundation.
Industrial Pressure Transmitter System Design Considerations and Major Challenges
To have an appropriate pressure transmitter system design, designers must consider many different system requirements including accuracy, zero drift,
temperature, and static pressure compensation.
• Characteristic compensation needs to be considered by means of temperature and static pressure signals, in addition to the differential pressure signal.
• Preventive maintenance function to detect sensor aging deterioration or any abnormality.
• Pressure transmitter product maximum range ability can be as high as 200:1, and the upper limit even up to 15,000 psi.
• Measurement accuracy can be high as 0.04% of full-scale range, which often requires a 16-bit to 24-bit analog-to-digital converter.
• Connectivity to different field buses like HART, PROFIBUS, Modbus, foundation, RS-485/RS-422/RS-232, wireless HART, and so on. Isolation might be needed
between sensors, conditioning circuits, system power supply, communication, and I/O; isolation grade varies from 1 kV to 2.5 kV.
• Isolation might be needed between sensors, conditioning circuits, system power supply, communication, and I/O; isolation grade varies from 1 kV to 2.5 kV.
• Both battery and loop-powered differential pressure transmitters require carefully selected ultralow power components like MCU, ADCs, and references.
Industrial site temperature environments are quite complex, even atrocious. Low temperature drift coefficient and low power consumption are very important
for differential pressure transmitters to endure wide working temperature ranges. ADI offers the perfect portfolio of precision amplifiers, precision references,
precision analog-to-digital converters, and low power ARM® Cortex™-M3 core microprocessors.
Besides that, EMC interference immunity under low power systems is also a big challenge for pressure transmitters, such as surge, EFT, and ESD. High level
ESD immunity components offered by ADI greatly help to improve reliability and robustness.
In addition, limited space inside the pressure transmitter is requiring dense systems. Therefore, the form factor has to be reduced to accommodate this.
Recently, advances in integration have allowed system designers to migrate to smaller, lower power, lower cost solutions, with performance approaching
those of larger systems. The challenge moving forward is to continue to drive the integration of these solutions, while increasing their performance and diagnostic
capabilities.
ADI offers market tailored solutions to aid in the design process. These solutions feature our industry-leading technologies and offer a range of design
options—from implementation of discrete components to fully integrated solutions, and everything in between.
Total Solutions from ADI
ADI’s amplifier, data conversion, signal processing, communications, and power technology and expertise provide leverage for high resolution, low noise, and
low power industry pressure transmitter systems.
instrumentation.analog.com
Signal Chain for Discrete Signal Conditioning
BATTERY
POWERED
OR
LINE
POWERED
OR
LOOP-POWERED
INTERFACES
POWER MANAGEMENT
DIFFERENTIAL PRESSURE
(MAIN VALUE MEASURED)
DC/DC
WIRELESS
LDO
RS-485/RS-422
IN-AMP
(PGA)
POWER
ISOLATION
PROFIBUS
PROCESSOR
STATIC PRESSURE
(COMPENSATION)
I/O
SIGNAL
ISOLATION
MCU
DAC
PWM
MUX
S-D
ADC
(24-BIT)
4mA TO 20mA
VREF
TEMPERATURE
(COMPENSATION)
V/I
DRIVER
HMI
KEYBOARD
+125 C
o
−40oC
(Note: dotted line sections may be optional or highly integrated according to various applications.)
Note: The signal chains above are representative of the system block diagram of a signal chain for discrete signal conditioning design. The technical requirements of the blocks vary,
but the products listed in the table below are representative of ADI's solutions that meet some of those requirements.
Signal Chain for Integrated Signal Conditioning
BATTERY
POWERED
OR
LINE
POWERED
OR
LOOP-POWERED
INTERFACES
POWER MANAGEMENT
DIFFERENTIAL PRESSURE
(MAIN VALUE MEASURED)
DC/DC
WIRELESS
LDO
S-D ADC
(24-BIT)
IN-AMP
(PGA)
VREF
S-D ADC
(24-BIT)
TEMPERATURE
(COMPENSATION)
POWER
ISOLATION
PROFIBUS
I/O
SIGNAL
ISOLATION
DAC
PWM
MUX
STATIC PRESSURE
(COMPENSATION)
PROCESSOR
MCU
RS-485/RS-422
4mA TO 20mA
V/I
DRIVER
HMI
KEYBOARD
+125 C
o
−40oC
(Note: dotted line sections may be optional or highly integrated according to various applications.)
Note: The signal chains above are representative of the system block diagram of a signal chain for integrated signal conditioning design. The technical requirements of the blocks
vary, but the products listed in the table below are representative of ADI's solutions that meet some of those requirements.
2 | ADI’s Pressure Transmitter Solutions
Main Product Introduction
Device
Description
Key Features
Benefits
ADC
AD7780/
AD7781
20-bit/24-bit, 1-channel, PGA,
sigma-delta ADC
Low power 500 μA maximum, 10 Hz to 16.7 Hz, 1 to 128 PGA,
p-p resolution over 17 bits
Cost very competitive + easy to use
AD7787/
AD7788/
AD7789/
AD7790/
AD7791
16-bit/24-bit, 1-channel/
2-channel, sigma-delta ADC
Ultralow power from 80 μA to 160 μA max, 9.5 Hz to 120 Hz,
50 Hz/60 Hz rejection
Ultralow power + small package
AD7796/
AD7797/
AD7798/
AD7799
16-bit/24-bit, 1-channel/
3-channel, sigma-delta ADC
with PGA
Low power 500 μA maximum, 4.17 Hz to 470 Hz, PGA 1 to 128,
reference, low noise
Low power + highly integrated with PGA
ADuCM360/
ADuCM361
Analog microcontroller
(ARM Cortex-M3 core)
Dual 24-bit Σ-Δ ADC (ADuCM360), single 24-bit Σ-Δ ADC (ADuCM361)
programmable ADC output rate (3.5 Hz to 3.906 kHz), 12-bit DAC,
programmable current sources, temperature sensor, internal reference,
4 ppm/°C, 16 MHz cortex, 128 kB flash, 8 kB RAM core consumes
290 μA/MHz, power-down mode: 4 μA (wake-up timer active)
Ultra low power, high precision,
leading integration chip solution
ADuCRF101
Embedded ISM band RF transceiver (862 MHz to 928 MHz and 431 MHz
to 464 MHz); Cortex-M3 32-bit processor, 16 MHz; 190 μA /MHz,
Analog microcontroller (ARM
Cortex in active mode; 1.6 μA, in power-down mode, MCU memory and
Cortex-M3 with RF transceiver)
transceiver memory retained; 128 kB/64 kB flash/EE memory, 16 kB/8 kB
SRAM; 6-channel, 14-bit or 12-bit ADC
Processor/MCU
ADUC7060/
ADUC7061
Analog microcontroller
(ARM7TDMI ® core)
Ultralow power, highly integrated with both
RF transceivers and analog channels
24-bit, 8 kSPS ADC, up to 10 ADC channels; 1-channel, 14-bit voltage DAC
outputs; 16-bit, 6-channel PWM; on-chip voltage reference ±10 ppm/°C
and temperature sensor; programmable sensor excitation current sources,
200 μA to 2 mA; up to 14 GPIO pins
High resolution, low power, and abundant
resources
AMP
AD8422
Instrumentation amplifier
Bandwidth = 2.2 MHz; Vos = 0.36 mV ; V NOISE density = 88 nV/√Hz;
IB = 1 nA; gain control interface = resistor; IQ = 330 μA; RRO
Third-generation AD620
AD8236
Instrumentation amplifier
Bandwidth = 23 kHz; Vos = 3.5 mV ; V NOISE density = 76 nV/√Hz; IB = 10 pA ;
gain control interface = resistor, Icc = 50 μA
Ultralow power and competitive price
AD8237
Instrumentation amplifier
Bandwidth = 200 kHz; Vos = 75 μV; drift 0.3 μV/ºC; gain error: 0.005%,
gain drift 0.5 ppm/ºC; IB <1 nA; single-supply: 1.8 V to 5.5 V; IQ = 150 μA
Low offset voltage, zero drift, low power,
and cost effective
AD8556/
AD8557
Instrumentation amplifier
Bandwidth = 2 MHz; Vos = 12 μV; VNOISE density = 32 nV/√Hz; IB = 25 nA;
gain control interface = digital
Good for fine tuning an analog transmitter
AD8276
Difference amplifier
Bandwidth = 550 kHz; Vos = 200 μV; VNOISE density = 70 nV/√Hz; low supply
Price competitive output solution for analog
current: 200 μA maximum per channel, rugged input overvoltage protection interface
AD5410/
AD5420
Current source DAC
12-bit/16-bit resolution; 0 mA to 24 mA ±0.01% FSR TUE;
±3 ppm/°C typical output drift; on-chip reference (10 ppm/°C maximum)
Universal output DAC and support HART
communication
AD5421
Current source DAC
16-bit resolution; 3.2 mA to 24 mA; NAMUR-compliant alarm; TUE error:
0.05% maximum; on-chip reference TC: 4 ppm/°C maximum
an range: 5.5 V to 52 V
Loop-powered universal output DAC
and support HART
AD5412/
AD5422
Current source and
voltage output DACs
12-bit/16-bit resolution; 0 mA to 24 mA ±0.01% FSR TUE; ±10 V with 10% Universal output with both voltage and
overrange ±0.01% FSR TUE; on-chip reference (10 ppm/°C maximum)
current
AD5660
nanoDAC ®
Single 16-bit, 5 ppm/°C on-chip reference; tiny 8-lead SOT-23/MSOP packages
Tiny package and high performance
AD693
Loop-powered sensor
transmitter
Loop-powered operation, instrumentation amplifier front end, precalibrated
30 mV or 60 mV input spans, precalibrated PT 100 interface, precalibrated
output spans, 4 mA to 20 mA unipolar, 12 ± 8 mA bipolar
A complete monolithic low-level, V-I, loop
signal conditioner
DAC
instrumentation.analog.com 
| 3
Main Product Introduction (Continued)
Part Number
Description
Temperature
Benefits
HART Modem
Low power HART modem
HART-compliant, fully integrated FSK modem, 1200 Hz and 2200 Hz sinusoidal
shift frequencies, 115 μA max in receive mode. Integrated receive bandpass filter, optional clocking configurations, buffered HART output,
2 V to 5.5 V power supply
Lowest power, smallest footprint,
on-chip oscillator
ADR29x
Voltage references
Initial accuracy: ±0.08% (maximum) maximum temperature coefficient:
8 ppm/°C; supply current 15 μA maximum
Super low quiescent current: 15 μA
(maximum)
ADR3412
Low power reference
1.2 V precision output, supply current: 100 μA max, low noise (<10 Hz):
8 μVp-p typ. Supply range: 2.3 V to 5.5 V, long term stability:
30 ppm/1000 hrs @ 50°C
Low power, small package
ADuM1100
Single channel digital isolators
2.5 kV rms; very low power operation, 3 V/5 V level translation;
high data rate: dc to 100 Mbps (NRZ)
Lowest power operation choice
ADuM140x
Quad channel digital isolators
2.5 kV rms; low power operation, 3 V/5 V level translation;
high data rate: dc to 90 Mbps (NRZ), output enable function
High data rate: dc to 90 Mbps (NRZ),
low power operation
ADuM744x
Quad channel digital isolators
1 kV rms isolation rating, low power operation; bidirectional communication,
Low power operation and competitive price
up to 25 Mbps data rate (NRZ), 3 V/5 V level translation
ADuM540x
Quad channel isolators with
integrated dc-to-dc converter
IsoPower integrated, isolated dc-to-dc converter, regulated 3.3 V or 5.0 V
output, up to 500 mW output power, high temperature operation: 105°C
Highly integrated isolation for both signal
and power
ADuM347x
PWM controller and
transformer driver with quad
channel isolators
Isolated PWM controller; integrated transformer driver; regulated adjustable
output: 3.3 V to 24 V; 2 W output power; 70% efficiency; quad dc-to-25
Mbps signal isolation channels; soft start function at power-up; thermal
shutdown, 2.5 kV rms isolation
More than 2 W output capability with good
efficiency and 200 kHz to 1 MHz adjustable
oscillator frequency
ADM2582/
ADM2587E
Isolated RS-485/RS-422
Half- or full-duplex, 16 M/ 500 kbps, 5 V or 3.3 V operation
Integrated isolated dc-dc ±15 kV ESD
ADM2483
Isolated RS-485 transceiver
with integrated transformer
driver
Half-duplex, 16 Mbps, integrated oscillator driver for external transformer,
5 V or 3.3 V operation, 50 nodes on bus
Low power operation and competitive price
ADM2485
Isolated RS-485 transceiver
with integrated transformer
driver
Half-duplex, 16 Mbps, Integrated oscillator driver for external transformer,
5 V or 3.3 V operation, 50 nodes on bus
PROFIBUS compliant
TMP05
Temperature sensor
±1°C accurate, 12-bit digital, PWM output interface, operation from 3 V to 5.5 V Small package with competitive price
ADT75
Temperature sensor
±1°C accurate, 12-bit digital, SMBus/I2C-compatible interface, operation
from 3 V to 5.5 V, over temperature indicator
Good performance with competitive price
ISM band FSK/GFSK/OOK/
MSK/GMSK transceiver IC
Frequency bands, 862 MHz to 928 MHz, 431 MHz to 464 MHz; ultralow
power; ISM band, data rates supported, 1 kbps to 300 kbps, single-ended
and differential power amplifiers
ISM band; data rate 1 kbps to 300 kbps;
very low power consumption
Multiplexers
4-channel/8-channel, 1.8 V to 5.5 V supply; 3 Ω maximum on resistance,
100 pA leakage current, up to 30 mA continuous current
Very low leakage current, cost competitive
AD5700/
AD5700-1
Ref
Isolator
Interface
Temp Sensor
Wireless
ADF7023
Mux
ADG759
4 | ADI’s Pressure Transmitter Solutions
Main Product Introduction (Continued)
Device
Description
Key Features
Benefits
Power
ADP2441
Step-down dc-to-dc regulator
Wide input voltage range of 4.5 V to 36 V, 1 A max, high efficiency of up
to 94%, ±1% ACC, adjustable switching frequency. 300 kHz to 1 MHz,
external soft start, overcurrent protection
Wide input range up to 36 V,
high efficiency, small package
ADP160
Linear regulator
2.2 V to 5.5 V input, 150 mA load current, 560 nA quiescent current,
195 mV @ 150 mA dropout voltage, PSRR 72 dB @ 100 Hz
Extremely low quiescent current,
high PSRR, low dropout voltage
ADP2108
Switching regulator
5.5 V input, 600 mA, 3 MHz, 18 μA quiescent current, 100% duty cycle,
1 μH inductor, SOT-23 package
Tiny solution size, small quiescent current,
and high light load efficiency
ADP1720
Linear regulator
Supply range: 4 V to 28 V, low light load current: 28 μA at 0 μA load, low
dropout: 275 mV @ 50 mA, initial accuracy: ±0.5%, enable logic control or
logic control enabled, current and thermal overload protection
Low power consumption
Reference Circuits
• Fully Isolated Input Module Based on the AD7793 24-Bit Σ-Δ ADC and the ADuM5401 Digital Isolator (CN0066)—www.analog.com/CN0066
• 4 mA to 20 mA Loop-Powered Temperature Monitor Using the ADuC7060/ADuC7061 Precision Analog Microcontroller (CN0145)—www.analog.com/CN0145
• Simplified 16-Bit, 4 mA to 20 mA Output Solution Using the AD5420 (CN0098)—www.analog.com/CN0098
• Weigh Scale Design Using the AD7781 20-Bit Sigma-Delta ADC with Internal PGA (CN0108)—www.analog.com/CN0108
• Precision Weigh Scale Design Using the AD7791 24-Bit Sigma-Delta ADC with External ADA4528-1 Zero-Drift Amplifiers (CN0216)—www.analog.com/CN0216
• Complete 4 mA to 20 mA Loop-Powered Field Instrument with HART Interface (CN0267)—www.analog.com/CN0267
• Complete 4 mA to 20 mA HART Solution with Additional Voltage Output Capability (CN0278)—www.analog.com/CN0278
• Complete 4 mA to 20 mA HART Solution (CN0270)—www.analog.com/CN0270
• 4 mA to 20 mA Loop-Powered Temperature Monitor Using the ADuC7060/ADuC7061 Precision Analog Microcontroller (CN0145)—www.analog.com/CN0145
• Complete Closed-Loop Precision Analog Microcontroller Thermocouple Measurement System with 4 mA to 20 mA Output (CN0300)—www.analog.com/CN0300
For more needs about pressure transmitters, please contact ADI.
Customer Interaction Center
Technical Hotline 1-800-419-0108 (India)
1-800-225-5234 (Singapore)
0800-055-085 (Taiwan)
82-2-2155-4200 (Korea)
Email [email protected]
EngineerZone ez.analog.com
Free Sample www.analog.com/sample
What ADI Can Provide to Customers
• ADC
• ADIsimADC—www.analog.com/zh/ADIsimADC
• Σ-Δ ADC register configuration assistant—
www.analog.com/SigmaDeltaRegisterConfigurationAssistant
• DAC
• ADIsimDAC—www.analog.com/ADIsimDAC
• Amp
• ADIsimOpAmp—www.analog.com/ADIsimOpAmp
• ADIsimDiffAmp—www.analog.com/ADIsimDiffAmp
• Power
• ADIsimPower—www.analog.com/ADIsimPower
• Processor
• Emulation tools and some software
instrumentation.analog.com 
| 5
Analog Devices China
Asia Pacific Headquarters
22/F One Corporate Ave.
222 Hu Bin Road
Shanghai, 200021
China
Tel: 86.21.2320.8000
Fax: 86.21.2320.8222
Analog Devices, Inc.
Korea Headquarters
6F Hibrand Living Tower
215 Yangjae-Dong
Seocho-Gu
Seoul, 137-924
South Korea
Tel: 82.2.2155.4200
Fax: 82.2.2155.4290
Analog Devices, Inc.
Taiwan Headquarters
5F-1 No.408
Rui Guang Road, Neihou
Taipei, 11492
Taiwan
Tel: 886.2.2650.2888
Fax: 886.2.2650.2899
Analog Devices, Inc.
India Headquarters
Rmz - Infinity
#3, Old Madras Road
Tower D, Level 6
Bangalore, 560 016
India
Tel: 91.80.4300.2000
Fax: 91.80.4300.2333
Analog Devices, Inc.
Singapore Headquarters
1 Kim Seng Promenade
Great World City
EastTower, #11-01
Singapore, 237994
Singapore
Tel: 65.6427.8430
Fax: 65.6427.8436
©2013 Analog Devices, Inc. All rights reserved.
Trademarks and registered trademarks are the
property of their respective owners.
BR11661-0-6/13
instrumentation.analog.com
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement