With the device for pressure measurement of temperature drift compensation
The present invention relates to a kind of device for pressure measurement with temperature drift compensation, belong to device for pressure measurement field.
The common working pressure sensor of device for pressure measurement.Conventional pressure transducer is a kind of semiconductor mechanical quantity Sensitive Apparatus, conventionally forms electric bridge, and its parameter is acted upon by temperature changes very large, and this impact is commonly referred to temperature drift (being called for short " temperature is floated ").The main temperature of pressure transducer float be Sensitivity Temperature float with zero point temperature float.
Document " mechanical quantity Sensitive Apparatus and application thereof " ((Beijing) Science Press, 1987) propose a kind of method compensating that Sensitivity in Pressure Sensors temperature is floated, its principle is to utilize diode in the time that forward uses (being that diode cathode current potential is higher than negative pole), to be equivalent to the characteristic of the resistance of negative temperature coefficient.As shown in Figure 1, one end ground connection of pressure transducer in pressure sensor module excitation input, the other end meets the first power output end VD1 after meeting the 4th diode D4 that at least one forward uses.But known by analyzing or testing, this connection can be aggravated the temperature at zero point of pressure transducer and be floated.
Document " temperature compensation of pressure transducer " (robotization and instrument, the 3rd phase in 2002) propose a kind of pressure transducer temperature at zero point to be floated to the device compensating, utilize single-chip microcomputer and temperature sensor in whole operating temperature range, the zero-point voltage of pressure transducer to be recorded in storer, when pressure survey, measure temperature at that time simultaneously, the output voltage of pressure transducer is deducted to the zero-point voltage of this temperature in storer, compensate zero point temperature with this and float.But, this device zero point temperature drift compensation is not rejected the impact that under the same pressure of pressure transducer, Sensitivity Temperature is floated, compensation precision is not high, and how the document keeps linear output and low cost not to propose specific implementation to this device critical component temperature sensor in larger operating temperature range.
How designing a kind of Sensitivity Temperature and float device for pressure measurement higher with zero point temperature drift compensation efficiency and that cost is low, is that person skilled is made great efforts the problem solving.
Summary of the invention
The object of the invention is to solve Sensitivity Temperature and float and the inefficient problem of zero point temperature drift compensation, provide a kind of compensating circuit simple, produce demarcate easily, the compensation effect device for pressure measurement with temperature drift compensation remarkable, with low cost.
In order to achieve the above object, the invention provides a kind of device for pressure measurement with temperature drift compensation, comprise power supply/battery module, power supply/battery module comprises the first power output end, it is characterized in that, described power supply/battery module is connected with one end of pressure sensor module by the first diode, the other end of pressure sensor module is connected with ground by the second diode, the output terminal of pressure sensor module is connected with the input end of amplifier and A/D module, the input end of amplifier and A/D module is also connected with the output terminal of temperature sense module, the output terminal of amplifier and A/D module is connected with the input end of message processing module, the output terminal of message processing module is connected with pressure survey output module.
Preferably, described message processing module comprises temperature drift compensation data-carrier store and zero point temperature drift compensation module.
Preferably, described temperature sense module comprises the 3rd diode and the resistance that at least one forward uses, and the negative pole of the 3rd diode is connected with ground, and the positive pole of the 3rd diode is connected with the power output end after amplifier and A/D module and resistance in series respectively.
Preferably, the two ends of described pressure sensor module connect respectively the first diode and the second diode that at least one forward uses, and the difference of the number of the number of the first diode and the second diode is not more than one.
The present invention adopts the first diode and the second diode pair compensation of α TCS that are sub-packed in pressure transducer excitation two ends, adopt the good diode sample temperature of wide temperature range output linearity to change, circuit is simple, element is without selecting coupling, production staking-out work is simplified easily, have and reduce costs, reach the good result of higher measuring accuracy simultaneously, compensation effect is remarkable.
Accompanying drawing explanation
Fig. 1 is traditional composition schematic diagram with diode pair Sensitivity in Pressure Sensors temperature drift compensation;
Fig. 2 is a kind of composition schematic diagram of the device for pressure measurement with temperature drift compensation.
Description of reference numerals
VD1 is the first power output end, and VD2 is second source output terminal, and D1 is the first diode, and D2 is the second diode, and D3 is the 3rd diode, and D4 is the 4th diode, and R is resistance.
For the present invention is become apparent, hereby with preferred embodiment, and coordinate accompanying drawing to be described in detail below.
Following examples are available to those of ordinary skills and realize and use of the present inventionly, but not in order to limit the present invention, anyly do not depart from the modification that the spirit and scope of the present invention are done, and are still included in scope of patent protection of the present invention.Protection scope of the present invention is with being as the criterion that claims were defined.
The present invention is a kind of device for pressure measurement with temperature drift compensation, as shown in Figure 2, is a kind of composition schematic diagram of the device for pressure measurement with temperature drift compensation.The present embodiment is a kind of engine oil pressure pickup, and operating temperature range is very wide, is-40 ℃ to+125 ℃, and reaches higher measuring accuracy.Pressure sensor module comprises the pressure transducer and the initial zero-regulator resistor that adopt silicon piezoresistive transducer chip, the two ends of pressure sensor module excitation input connect respectively the first power output end VD1 and the ground that connect respectively power supply/battery module after the temperature drift compensation diode that a forward uses again, the first power output end VD1 connects the positive pole of a temperature drift compensation first diode D1, the negative pole of temperature drift compensation the first diode D1 connects one end of pressure sensor module excitation input, the positive pole of another temperature drift compensation of its another termination the second diode D2, temperature drift compensation the second diode D2 minus earth.Temperature sense module is made up of the 3rd diode D3 and resistance, and the 3rd diode D3 forward in-40 ℃ to+125 ℃ temperature ranges uses, and its exporting change still can keep good linearity.The 3rd diode D3 minus earth, anodal work meets second source output terminal VD2 after output resistance in series.Output access amplifier and the A/D module of pressure sensor module, the output of temperature sense module also accesses amplifier and A/D module, by amplifier and A/D module, A/D after the pressure signal of acquisition and temperature signal amplification is converted to digital quantity and is transferred to message processing module.Message processing module comprises temperature drift compensation data-carrier store and zero point temperature drift compensation module, one of their implementation method be use comprise microcontroller add write computer program realize.
The present invention is producing timing signal, zero point temperature drift compensation module can be in daily atmospheric pressure and full operating temperature range output sampling the A/D conversion of the output to temperature sense module and pressure sensor module, be recorded in non-volatile temperature drift compensation data-carrier store, the for example flash memory in microcontroller (FLASH), zero point temperature drift compensation module reads the relation table of setting up temperature and pressure sensor zero point after the data in temperature drift compensation data-carrier store.
When surveying work of the present invention, zero point temperature drift compensation module can be applied this relation table the output of pressure sensor module is carried out to zero point temperature drift compensation.Temperature drift compensation the first diode D1, temperature drift compensation the second diode D2 float and compensate Sensitivity in Pressure Sensors temperature, therefore, through Sensitivity Temperature float with zero point temperature drift compensation after pressure measuring value precision higher, can export by pressure survey output module.Pressure survey output module generally includes digital signal output buffer or serial data delivery outlet or D/A converter or PWM (width modulation) delivery outlet, respectively with the formal output pressure measuring value of parallel data, serial data, voltage/current amount, pwm signal.
The diode at pressure transducer of the present invention excitation two ends adopts one, each end, also can respectively hold multiplely, and its sum floats coefficient to the Sensitivity Temperature of pressure transducer and is directly proportional.Pressure transducer encourages the number of the first diode D1 and the number of the second diode D2 at two ends to equate as far as possible, and the difference of both quantity is not more than one, floats to reduce the temperature at zero point causing thus.
The 3rd diode D3 that the forward of temperature sense module of the present invention uses can adopt multiple series connection, respectively the negative pole of the 3rd diode D3 is connected with the positive pole of another the 3rd diode D3, the minus earth of last the 3rd diode D3, after the cathode series resistance R of the junior one a 3rd diode D3, meet second source output terminal VD2, and this positive pole is done the output of temperature sense module.Can increase like this sensitivity of temperature sense module output.