At present time the improving of technological processes is very important for most of manufacturing companies. As known, the quality performance is impossible without monitoring of defined technological characteristics, particularly, temperature and pressure and others. For example, the values of pressure can characterise the ambience in technological processes of petrochemical industry when chemical processing of natural and synthetic substances. The maintenance of defined pressure level is sufficiently important task when using complicated devices, machines and other technique applied for different research works. Pressure measuring tools in automobile industry are being used in order to sustain the motor operation and safety of other systems. Iit's evident, that the measuring systems are characterised by rather strict requirements to both working characteristics and geometrical sizes and conponents design.

Among leading world producers of measuring devices and pressure contorolling systems in complicated industrial and laboratory equipment one can note TDK (Epcos). High-precision sensors developed by the company allow to get complex data on absolute and gage pressure in settings usable in different fields of application. Produced components are calibrated and have the built-in circuit with thermal compensation. The measurement accuracy is no more than 1%. Main advantages of Epcos sensors: miniature sizes of a case, high accuracy, stability of characteristics, reliability when operating. The absence of expensive materials in sensors and the easy construction allow to produce components with low cost in commercial batches.

The operating principle of Epcos sensors is based on piezoresistive effect. Particularly, mechanical strength appears due to the pressure overfall on different parts of a diaphragm seal. This leads to the sensor resistance changing. Piezoresistors are connected in a Wheatstone bridge and allow to convert tha resistance changing to the electrical signal. The value of this electrical signal is proportional to the value of applied pressure. The ambient pressure impacts on a sensitive element causes its deformation. The temeprature diffrence between surface which is in a contact with ambience and planar side leads to appearance of a heat flow within its volume. Under the impact of pressure and temperature piezoresistors and thermoresistors change its resistance proportionally deformation and temperature difference correspondingly. The changes are being converted in a bridge circuit to the voltage and current signals. After correction these signals are transmitted to the measuring receiver. The application of silica sensor converter allows to increase temporary and temperature stability of devices in comparance with other elements dor pressure measuring. depending on fields of application sensors can be used as a crystall - sensitive element and also as a sensor placed in a hermetic package wich allows to determine the power pressure.

Absolute pressure sensor dies need a vacuum as a reference point for the pressure to be measured. This reference vacuum is created by bonding the sensor to a solid glass base.

In case when measurements are being conducted in severe conditions and also in water environment it is recommended to avoid the application of chip's front side. These terms are being realized when using the enter of an opposite sensor side for a contact with the measured medium and creation of the field with vacuum on a front side.

Differential Pressure Sensors A pressure difference caused by a higher front side pressure leads to a positive change of the output signal. A higher back side pressure leads to a negative change of the output signal. A differential pressure sensor can be used for flow measurement by measuring the pressure drop across a restrictor.

Gauge Pressure Sensors A gauge pressure sensor is a special case of a differential pressure sensor where either the front or the back side is exposed to ambient pressure.

Pressure sensor dies

Pressure sensor dies consist of a piezoresistive silicon element with an anodically bonded glass base. Gauge pressure sensor dies with pressure to front and back side as well as absolute pressure sensor dies with pressure to front side are available. The C29 and C32 pressure sensor dies were developed for absolute pressure measurements in wet media. The difference to conventional absolute pressure sensor dies is the reference pressure chamber which is bonded to the front side and the pressure is applied to the back side.

Main technical characteristics:

Series	Rated pressure ranges, bar	Pressure measurement	Ta , °C	Umax, В	Dimensions, mm	Ordering code	Detailed information
С 41	0.025...0.060	Gauge/back side Measured media: Non-aggressive fluids and gases	-40...+135	10	5.05x5.05	B58601G5010A001 B58601G5010A002
С 27	0.025...1.0	Absolute/front side Measured media: Dry non-aggressive gases	-40...+135	10	3.05x3.05	B58600C5010A003 B58600C5010A004 B58600C5010A005
С 27	0.1...1.0	Gauge/Back side Measured media:Non-aggressive fluids and gases	-40...+135	10	3.05x3.05	B58601C5010A006 B58601C5010A007 B58601C5010A008 B58601C5010A009
С 28	2.5...25.0	Absolute/Front side Measured media: Non-aggressive fluids and gases	-40...+135	10	2.05x2.05	B58600D8010A011 B58600D8010A012 B58600D8010A013 B58600D8010A014
С 28	2.5...25.0	Gauge/back side Measured media: Non-aggressive fluids and gases	-40...+135	10	2.05x2.05	B58601D8010A016 B58601D8010A017 B58601D8010A018 B58601D8010A019
С 28	2.5...25.0	Gauge/Front side Среда: Dry non-aggressive gases	-40...+135	10	2.05x2.05	B58601D8010A024 B58601D8010A025 B58601D8010A026 B58601D8010A027
С 29	1.0...10.0	Absolute/back side Measured media: Non-aggressive fluids and gases	-40...+135	10	2.2х2.7	B58600E0410A020 B58600E0410A021 B58600E0410A022 B58600E0410A023 B58600E0410A002 B58600E0410A003 B58600E0410A00 B58600E0410A005
С 32	1.6...25.0	Absolute/back side Measured media:Non-aggressive fluids and gases	-40...+135	10	1.65х1.65	B58600H8400A037 B58600H8400A039 B58600H8400A038 B58600H8400A040
С 32	1.6...25.0	Absolute/Front side Measured media: Non-aggressive fluids and gases	-40...+135	10	1.65х1.65	B58600H8000A001 B58600H8000A002 B58600H8000A003 B58600H8000A004
С 32	1.6...25.0	Gauge/Back side Measured media: Non-aggressive fluids and gases	-40...+135	10	1.65х1.65	B58601H8000A035 B58601H8000A033 B58601H8000A036 B58601H8000A034
С 33	1.0...1.0	Absolute/face side Measured media: Non-aggressive fluids and gases	-40...+135	10	1.2	B58600I0000A001

Pressure sensors

АК2, АТ2, ASB 1200, T5100 Epcos sensorsare produced on the base of MEMS-technology. As in the case of sensors C27...C33 piezoeffect is been used in this series. AK2 and АТ2 have a strong casing made of steel/plastics and are characterised by improved mechanical properties. output signal is fixed without calibration and thermal compensation. T5100 components for pressure measuring are based on sensors series with monocrystall C33. A signal from a bridge circuit goes to the receiver without calibration and thermal compensation. All goods correspond RoHS.

Main technical characteristics:

Series	The range of working pressure, bar	Measurement media	Ta , °C	Umax, В	Dimensions, mm	Ordering code	Detailed information
AK2, KD	0,025...0,4	Gauge Media: Non-aggressive gases and fluids	-40...+125	10		B58611K1100A00 B58611K1100A002 B58611K1100A003 B58611K1100A004 B58611K1100A005
AK2, KС тип	1,0...25,0	Gauge Medua: Non-aggressive gases and fluids	-40...+125	10		B58611K1100A006 B58611K1100A007 B58611K1100A008 B58611K1100A009 B58611K1100A010
AT2	1,0...25,0	Absolute Media: Non-aggressive gases	-40...+125	10		B58610T4600A001 B58610T4600A002 B58610T4600A003 B58610T4600A004 B58610T4600A005 B58610T4600A006 B58610T4600A007
T5100	1,2	Absolute Media: Non-aggressive gases	-40...+125	10		-

Additional information

Full databook on pressure sensors

Полная информация по всем сериям датчиков давления представлена в полном каталоге Epcos.

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