CN1370982A

CN1370982A - Electronic thermometer integrated circuit

Info

Publication number: CN1370982A
Application number: CN 01103894
Authority: CN
Inventors: 陈敏镛; 谢志伟
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-02-21
Filing date: 2001-02-21
Publication date: 2002-09-25
Anticipated expiration: 2021-02-21
Also published as: CN1177564C

Abstract

The electronic thermometer integrated circuit has built-in resistor-capacitor combinatino and logic switch control system or formula compensation parameter list to correct system target values. Proper resistor-capacitor combination is selected and read into built-in or outer memory, or proper compensating resistor-capacitor combination is maintained in fuse mode. System vibration frequency and low battery voltage value are regulated to target values, so that the vibration frequency is uniform and the thermometer producing process is simplified.

Description

Electronic thermometer integrated circuit

The present invention relates to a kind of electronic thermometer integrated circuit (IC), particularly utilize the permutation and combination choose resistance, electric capacity, make the manufacturing process of clinical thermometer more simple and easy, IC circuit efficiently, and make the more perfect function of clinical thermometer.

The production run of existing clinical thermometer, be with thermistor and center resistance size according to its resistance value, be divided into several classifications, again with similar collocation production, because the positive negative error of this kind mode reaches 600 Ω and (approximates 0.6 ℃, and countries in the world are ± 0.1 ℃ to the accuracy requirement of clinical thermometer), cause the classification of classification limited, so very easily produce when making measure inaccurate, and because the classification of classification is too much, cause the stock to hoard and produce the collocation difficulty, increased production cost.

Fundamental purpose of the present invention is to provide a kind of electronic thermometer IC circuit, utilizes choosing and the combination of compensating parameter of resistance and electric capacity assembled arrangement, makes making more simple and easy, and makes the temperature of calculating out more accurate.

Described IC circuit, it is the compensating parameter table of setting up the combination of resistance and electric capacity and logic switch control system or formulism in IC inside, utilize software and hardware predetermined target value with corrective system, choose optimal compensating resistance and capacitance group permutation and combination or with optimal parameter group in the parameter list, the combination of choosing is write EEPROM or memory built-in or that add, to obtain predetermined target value.

Described IC circuit utilizes hardware and software predetermined target value, in the serial or parallel connection mode, chooses the permutation and combination of optimal compensating resistance and electric capacity, utilizes voltage, the current fusing mode of increasing, to keep the combination or the parameter group of resistance and electric capacity.

Described IC circuit is by RC oscillation principle decision systems oscillation frequency, and according to the predetermined target value of external software, resistance and electric capacity is compensated individually or simultaneously.

Described IC circuit comprises a logic judging circuit, before start and showing measured value, carries out Celsius (℃) and Fahrenheit (°F) switching, and with the result of sound and literal demonstration switching.

Described IC circuit at display (L.C.D) the demonstration English words ok and the go of clinical thermometer, with the clear testing result that shows, prevents the erroneous judgement of measured value, guarantees user's measurement safety.

Electronic thermometer IC circuit of the present invention makes the process of making electronic thermometer more simple and easy, and it is more accurate to measure temperature.

Principal feature of the present invention and novelty thereof will cooperate the following drawings and embodiment to describe in detail.

Fig. 1 is a making embodiment synoptic diagram of the present invention.

Fig. 2 is a corrective system synoptic diagram of the present invention.

Fig. 3 is that of the present invention another made the embodiment synoptic diagram.

Fig. 4 is an operational flowchart of the present invention.

Fig. 5 is an operational flowchart of the present invention.

Please consult Fig. 1,2 simultaneously, the present invention includes the inner resistance of setting up of clinical thermometer IC1 and electric capacity combination 11 and logic switch control system 12, or the compensating parameter table 13 of formulism, wherein, the C of IC1 _Osc, R _OsoBe the electric capacity and the resistance of decision systems oscillation frequency, R _LVBe the resistance of decision power shortage caution signal, TM is a thermistor, R _RefBe center resistance, except this thermistor TM, each basic resistance and capacitor C _Osc, R _Osc, R _LV, R _RefAll can be built-in or be external in IC1.

The present invention in process of production, use corrective system as Fig. 2, utilize software and hardware predetermined target value, choose optimal compensating resistance and capacitance group permutation and combination 11, or the optimal parameter group in the parametric compensation table 13, resulting combination is write EEPROM (or storer) 14 built-in or that add, make the program of IC1 read the interior resistance of this EEPROM14 and electric capacity combination or compensating parameter combination, after calculation, can obtain predetermined target value.

Please consult Fig. 2,3 simultaneously, the present invention also can be in process of production, utilize the corrective system (not being transported to EEPROM or memory) of Fig. 2, use software and hardware predetermined target value, mode with serial or parallel connection, choose optimal compensating resistance and electric capacity permutation and combination, utilize the mode that increases voltage, current fusing circuit, keep combination of aforementioned compensating resistance and electric capacity or parameter group.

No matter and with Fig. 1 or Fig. 3 mode, because the built-in temperature estimation formula of IC1 is to select when a certain specific (temperature is as 37 ℃) water temperature, when the center resistance value is the thermistor of a fixed value (as 30k Ω), the impedance that is had, temperature relation, in manufacturing process, allowing the center resistance error of thermistor is 1% (is 29.7k to 30.3k as 37 ℃ center resistances), nonlinear characteristic according to thermistor, the thermistor of concentricity resistance not, the relation of its impedance and temperature is also inequality, so that cause the error when measuring, especially when voltage is on the low side, by the present invention, in the predetermined value of self correcting system, choose suitable combination of collocation resistance or parameter, in order to compensate the error that different impedances and temperature relation are caused, make measurement result accurate, and in large-scale production run, at an easy rate the system oscillation frequency is adjusted to desired value, and make the oscillation frequency in thermistor and loop thereof and the center resistance of thermistor collocation and the oscillation frequency in loop tend to consistent, having improved existing clinical thermometer need be with the complicated manufacturing process of a large amount of human resource management resistance and electric capacity, and can can't keep stable thermistor compensation to producing the back resistance, make its temperature value more accurate.

See also Fig. 4,5, the present invention also comprises logical circuit and singly-bound handoff functionality, the selftest function of general clinical thermometer, all show with optional network specific digit, as: 37.0 ℃ or 42.0 ℃ or 36.5 ℃ of expressions, can't allow clear understanding of user and easily produce and obscure, the present invention is when the IC logical design, increase another L.C.D. stroke (as tiltedly adding a stroke in 8 bottom rights) to constitute the ok printed words to show English words k, or show with the go printed words, can allow the user fully understand the Function detection result, avoid obscuring, to guarantee user's safety with the normal temperature measured value.

As shown in Figure 5, the present invention also can increase logic judging circuit in IC, after start and before showing measured value, when making up by same switch key fixed number of times and certain time, carry out the switching of (℃) and () Celsius, and show switching result, at this moment with sound and literal, the unit of measured value after with conversion show, as:

In back one second of start, when pressing switch key above 1.5 seconds, the expression Fahrenheit (°F) and Celsius (℃) handoff functionality, after switching was finished, value for storage made zero, the hummer sounding, when being converted to when Celsius, L.C.D. shows ℃ flicker, and when being converted to Fahrenheit, L.C.D. show flicker, decontrol back 2 seconds until button.

More than for this case for embodiment, only for convenience of explanation, should not limit the scope of this case, the various shift design of the present invention should be included in the claim of this case.

Claims

1, a kind of electronic thermometer IC circuit mainly comprises:

Set up the compensating parameter table of the combination of resistance and electric capacity, logic switch system or formulism in IC inside;

Corrective system is utilized software and hardware predetermined target value, chooses optimal compensating resistance and electric capacity permutation and combination, or the optimal parameter group in the parametric compensation table;

Aforementioned selected combination is write EEPROM or memory built-in or that add, make the built-in program of IC read the combination of resistance and electric capacity or the combination of compensating parameter.

2, electronic thermometer IC circuit as claimed in claim 1, wherein, the compensating parameter of this resistance and electric capacity combination or formulism, also can utilize the desired value of software and hardware, in the serial or parallel connection mode, choose optimal compensating resistance and electric capacity permutation and combination, utilize to increase voltage, current fusing circuit mode, keep combination of selected compensating resistance and electric capacity or parameter group.

3, electronic thermometer IC circuit as claimed in claim 1 wherein, comprises a logic judging circuit in this IC circuit, carry out Celsius (℃) and Fahrenheit (°F) switching, and after switching, upgrade or the storage memory value of the former storage of making zero, and show switching result with sound and literal simultaneously.

4, electronic thermometer IC circuit as claimed in claim 1, wherein, this IC circuit comprises a self-test circuit, sentences specific cypher in the display screen of clinical thermometer and shows testing result, obscures with the normal temperature measured value avoiding.