CN2058982U - Temp. transducer for computer - Google Patents

Abstract

The utility model relates to a production taking a thermistor as a temperature sensor for computer. A future time base block is taken as the main element of a resistor and frequency conversion circuit, the loop of an instant time base block from power end to earth end is connected with a triode, the thermistor and a capacitor in turn, and a diode is connected between the base electrode and the emitting electrode of the triode. The high and low triggered ends of the time base blocks are connected to a crossing point between the thermistor and the capacitor after connection. Since frequency is output, the count interface circuit of the computer can be utilized with convenience, low cost and high precision.

Description

Temp. transducer for computer

The utility model relates to the making of a kind of computing machine of time spent matrix formation with temperature sensor.

The existing technical scheme that adopts thermistor to make temperature sensor has multiple, as converting resistance value to respective frequencies, the multivibrator that adopts transistor or TTL to constitute, there is corresponding relation between its oscillation frequency and the thermistor resistance, but because of the electric current by thermistor big, influenced accuracy of detection, and adopt resistance bridge and amplifying circuit that the parameter of thermistor is transformed into electric signal, its anti-interference is poor, poor stability, and precision is not high yet, be connected inconvenient with computing machine, if improve precision, then need adopt high performance device, as high-precision modulus conversion chip etc.

The utility model is in order to overcome above-mentioned shortcoming, and a kind of ratio of performance to price height of making, and the precision height can directly connect the temperature sensor of computing machine.

The technical solution of the utility model such as following: thermistor is made temperature sensor,, the temperature-resistance of thermistor relation is transformed into temperature-frequency relation by the resistance-frequency-conversion circuit of a high precision high stability.Particularly: utilize basic integrated package in a period of time ［ 555 ］ to make the multivibrator of resistance-frequency transformation, with loop that thermistor is connected in, the triode of connecting replaces fixed resistance, promptly from the time matrix power end ［ 8 ］ extremely hold successive the loop of ［ 1 ］ connect triode, thermistor, the electric capacity of collector, emitter access; The high-triggering end and the low triggering end ［ 2 of base integrated package when lead-in wire connects between thermistor and the electric capacity, 6 ］, reset terminal ［ 4 ］ connects noble potential, connect diode between the emitter of triode and the base stage, and its anodal sending and receiving emitter-base bandgap grading, negative pole connects base stage, and the discharge end ［ 7 ］ of base integrated package when being connected to, voltage controling end ［ 5 ］ also connects a resistance by string one capacity earth between power end and discharge end, output terminal ［ 3 ］ just can obtain the frequency signal corresponding with the thermistor resistance.This sensor can be connected with the computing machine of any model by the counting interface circuit.Because its output loading capability is big, can be earlier direct driven for emitting lights device-, be connected with the counting interface circuit again by optically-coupled as light emitting diode.This and computer interface circuits make computing machine and external sensor not have being connected of electricity, can improve the antijamming capability of system greatly, and the circuit of this sensor is simple, cost is low, stable performance, conversion accuracy height, low in energy consumption, the resolution height is suitable for remote remote measurement, can be widely used in the temperature survey and automatic control of various industries.

The utility model is described in further detail below in conjunction with accompanying drawing:

Fig. 1 is a structural representation of the present utility model, thermistor ［ Rt ］ is selected the kind of high stable for use,＜need only in the temperature-measuring range of thermistor as available MF51 type, the utility model always can be made corresponding frequencies output 〉, generally between-80 degrees centigrade to+300 degrees centigrade, divide five kinds of temperature sections, the time matrix can be with homemade 5G1555 type＜also available other 555 type products in the world 〉, the available general miniwatt NPN type switch triode of triode ［ G ］＜as 3DK3 etc. 〉, the available general miniwatt germanium switching diode of diode ［ D ］, the value of electric capacity ［ C1 ］ is pressed the thermistor characteristic and is determined as 2AK9 etc., electric capacity ［ C2 ］ selects 0.01 μ, resistance ［ R ］ selects 1K-8K, and the element of other model also can be used certainly.Its output terminal can connect the counting interface circuit of various model computing machines, as can be used for TP series microcomputer, PC series microcomputer, single-chip microcomputer, STD industrial computer.Computing machine receive frequency count value has directly reflected the resistance-temperature of thermistor.The time connect an electric capacity ［ C1 ］ between the high-triggering end of matrix and low triggering end and the ground end span and thermistor characteristic, computing machine maximum count value and the frequency measurement software of counting the interface circuit passage relevant, its common span is that the frequency of matrix output terminal ［ 3 ］ when making is between 5KHz to 65KHz.

More than be essential element of the present utility model and connection thereof, and simple extension does not on its basis all exceed scope of the present utility model.

Claims (3)

1, a kind of temperature sensor of time spent matrix formation, elements such as matrix, thermistor, triode, diode, resistance when comprising, it is characterized in that from the time matrix power end [8] extremely hold triode, thermistor, the electric capacity that successive series connection collector, emitter insert the loop of [1]; The high-triggering end and the low triggering end [2 of base integrated package when lead-in wire connects between thermistor and the electric capacity, 6], reset terminal [4] connects noble potential, connect diode between the emitter of triode and the base stage, and its anodal sending and receiving emitter-base bandgap grading, negative pole connects base stage, and is connected to the discharge end [7] of time base integrated package, voltage controling end [5] also connects a resistance [R] by string one capacity earth between power end [8] and discharge end [7].

2, the temperature sensor of being addressed by claim 1 connects a resistance ［ R ］, its span 1K to 8K between the power end of matrix and the discharge end when it is characterized in that.

3, the temperature sensor of addressing by claim 1, the span that connects an electric capacity ［ C1 ］ when it is characterized in that between the high-triggering end of matrix and low triggering end and the ground end is relevant with maximum count value and frequency measurement software that thermistor characteristic, computing machine are counted the interface circuit passage, and its common span is 0.0005 μ to 0.1 μ.