P51 pressure sensor

             PS-AN2 MediaSensor™ Absolute, Sealed, Gage Pressure Sensors Family Product Overview

Product Description：

The MediaSensor™ (P51) family of bulk micro-machined, absolute, sealed and gage pressure sensors are for both harsh and benign media with superior accuracy over an operating temperature of -40°C to 105°C. These compact, robust sensors measure pressures from 3 PSI to 5,000 PSI and are well suited for a variety of automotive, industrial and commercial applications.

Product Features
Superb Accuracy:
o +/- 0.5% Full Scale for 75 PSI to 5000 PSI
o +/- 1% Full Scale for 15 PSI to 60 PSI
o +/- 2% Full Scale for 3 PSI to 10 PSI
Pressure Ranges: 3 PSI to 5,000 PSI
Electronics:
o 0.5 – 4.5 Volt output (with 5V input)
o 0.5 – 4.5 Volt output with overvoltage protection (with 5V input)
o 1-5 Volt non output (with 8 - 30V input)
o 4 – 20 mA output (with 8 - 30V input)

Temperature Range: -40°C to 105°C
Maximum Flexibility: Custom ASIC provides signal conditioning for calibration and temperature compensation.

Standard and custom options available for OEM quantities

Excellent price/performance ratio

MediaSensor™ Family of Pressure Sensors with integrated signal conditioning
Compact, Robust Package: All laser-welded stainless steel design for optimal media isolation in compact size

Chemical Compatibilities: Any gas or liquid compatible with 304L & 316L Stainless Steel. For example, Motor Oil, Diesel, Hydraulic fluid, brake fluid, water, waste water, Hydrogen, Nitrogen, and Air.

Typical Applications: Refrigeration; Fuel Cells; Pumps; Hydraulics; Process Control; Spraying Systems; Pneumatics; Compressors; Flow; Robotics; Agriculture; Hydrogen Storage
 
Standard Full Scale Pressure Ranges
Gage: 3, 5,10, 15, 25, 30, 50, 60, 75, 100, 120, 130, 200, 225, 250 and 300 PSIG
Sealed: 50, 100, 150, 200, 300, 400, 500, 750, 1000, 1500, 2000, 3000 and 5000 PSIS
Absolute: 15, 30, 50, 65, 75, 100, 150, 200, 250, 300, 500, 750, 1000, 1500, 2000, and 3000 PSIA

Measurement Technology
In general, pressure measurement technology translates force from an induced pressure into an electrical quantity. The MediaSensor™ family of pressure transducers and transmitters use piezoresistive technology for its sensor signal processing to measure pressure.
A micro-machined stainless steel convoluted diaphragm with a silicon crystal semiconductor is used. Strain gauges (resistive elements) in the silicon crystal are used in a Wheatstone Bridge circuit. When pressure is applied, the resistivity of the strain gauges changes proportional to the pressure applied. Since a single silicon crystal is used it has a low mechanical hysteresis with good linearity.
One leg of the bridge measures the input pressures port. The other leg of the bridge is connected to the reference port the input pressure port is compared to. The connection to this reference port determines the pressure sensing convention used.
The MediaSensor™ family comes in a choice of three pressure sensing type conventions: absolute, gauge (vented or sealed).
Absolute MediaSensors™ measure pressure relative to perfect Vacuum pressure (0 PSI) which remains unchanged regardless of temperature, location or other ambient conditions such as weather. Absolute MediaSensors™ are calibrated to have 0.5 Vdc, 1 Vdc, or 4 mA respectively at 0 PSIA.
There are two different gauge pressure conventions – Vented Gauge and Sealed Gauge. Gauge MediaSensors™ measure pressure relative to ambient room pressure through a port that is vented (open) to the atmosphere. Gauge MediaSensors™ are calibrated to have 0.5 Vdc, 1 Vdc, or 4 mA respectively at 0 PSIG.
Sealed MediaSensors™ measure pressure relative to a port that is connected to a sealed perfect vacuum chamber. Sealed MediaSensors™ are calibrated to 14.5 PSI absolute. Sealed MediaSensors™ are calibrated to have 0.5Vdc, 1 Vdc, or 4 mA respectively at 14.5 PSIA.
The MediaSensor™ takes the two voltage output ports of the Wheatstone bridge and amplifies the signal. Piezoresistive pressure sensors are sensitive to changes in temperature. The MediaSensor™ uses signal conditioning to compensate for temperature and calibration. The output signal is then converted into one of four forms:
1) 0.5 – 4.5 Volt ratiometric output (transducer)
2) 0.5 – 4.5 V ratiometric output with Overvoltage protection (transducer)
3) 1 – 5 volt output (transducer)
4) 4 – 20 mA output (transmitters)
 
Ratiometric outputs vary as a ratio of the supply voltage.
Transmitters are very suitable in applications that use long cables. There is virtually no error from voltage drop introduced from the wire resistance when sending the signal as a current. They are also less sensitive to electromagnetic interference.
Some piezoresistive pressure transducers use only an unprotected silicon sensing element. Silicon is a brittle crystalline material, which can sometimes crack under severe cold transient environments. The MediaSensor™ pressure transducer uses an additional 316L stainless steel convoluted diaphragm with a protective non-silicone oil to protect the sensitive silicon sensing element from the harsh media and environmental conditions. The 316L stainless steel diaphragm not only provides for optimal water and chemical media isolation for the silicon crystal sensing element but can handle cold temperature transients without sustaining damage.
Under cold transient conditions and within our operating temperature range, the oil does not gel and acts as a buffer for the silicon sensing element from the extreme temperature transients found in certain applications such as refrigeration.
MediaSensor™ Compensations Features
All the compensation circuitry is internal to the MediaSensor™ pressure transducer. No external compensation modules are needed.
1) Zero balancing (Null Offset) Calibration

During manufacturing the Wheatstone Bridge resistive elements are closely matched and compensated, however an offset voltage (due to resistance differences) may still exist. SSI MediaSensor™ compensates for this offset over operating temperature range (refer to Table 1).
2) Span Calibration
The resistance of silicon gauges is temperature dependent. The span will shift with temperature to a final stabilized value as it warms up. SSI MediaSensor™ compensates for this span variation over operating temperature range.