CN207181498U - A kind of power control of digital multimeter - Google Patents
A kind of power control of digital multimeter Download PDFInfo
- Publication number
- CN207181498U CN207181498U CN201721135013.5U CN201721135013U CN207181498U CN 207181498 U CN207181498 U CN 207181498U CN 201721135013 U CN201721135013 U CN 201721135013U CN 207181498 U CN207181498 U CN 207181498U
- Authority
- CN
- China
- Prior art keywords
- circuit
- digital multimeter
- power control
- resistance
- triode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Abstract
It the utility model is related to a kind of power control of digital multimeter, the digital multimeter includes a battery BAT, one power switch K and one digital multimeter measuring circuit of interconnection and a display screen, power control includes a power control circuit and a voltage detecting circuit, one end of the power switch K connects the positive pole of the battery BAT, the other end connects the power control circuit and voltage detecting circuit respectively, the power control circuit is also connected with the digital multimeter measuring circuit, the voltage detecting circuit is additionally coupled to the power control circuit；The digital multimeter measuring circuit, voltage detecting circuit are connected to the battery BAT negative poles.The utility model has the advantage of：Can ensure that shown measured value is accurately and reliably numerical value to digital multimeter in use, avoid cell voltage it is too low when, the measured value shown by digital multimeter is inaccurate or mistake causes user to make erroneous judgement or injured.
Description
Technical field
The utility model belongs to electronic measuring technology field, more particularly to a kind of power control of digital multimeter,
It is applied to battery powered digital multimeter.
Background technology
Digital multimeter has measurement combined-voltage, ac and dc current, the function such as resistance, be tested ac voltage signal by
Input inputs digital multimeter, through decay, AC/DC conversions, after analog-to-digital conversion, is exported by display driver circuit, drive LCD or
The displays such as LED show tested magnitude of voltage.However, in actual measurement process, the AC/DC conversions in digital multimeter, modulus turn
The circuit power power supply such as changing needs a voltage range, ensures the normal work and display regime values of its circuit.However, adopt
The supply voltage of battery-powered digital multimeter can be gradually reduced with usage time, when the supplying cell of digital multimeter
When voltage is declined to a certain extent, digital voltage measuring instrument typically has battery low-voltage instruction.However, due to power supply power supply electricity
Reduce off-flavor can often produce the numerical value of mistake, and the numerical value still can be shown in face over the display, as shown in figure 1, the number that a kind of LCD is shown
Word universal meter, using IC17106 integrated circuits, its normal working voltage scope 7V-12V, can typically show during less than 7V "
" symbol reminds user, but now IC is in abnormal operating state, display screen measures aobvious still in dispaly state
Indicating value is probably mistake.This phenomenon can mislead user, and user is possible to will be considered that test line voltage is not powered
Or line work is carried out in low-pressure state, cause user the danger such as to be injured.
Utility model content
In order to solve the above-mentioned technical problem, the utility model provides a kind of power control of digital multimeter, works as electricity
When cell voltage is less than the magnitude of voltage set, the operating voltage of digital multimeter measuring circuit is closed, makes digital multimeter measurement electricity
Road is stopped, so as to avoid the measurement data that user surveys because of reading is present larger error or completely by mistake damage.
The technical solution of the utility model is as follows：
A kind of power control of digital multimeter, the digital multimeter include a battery BAT, a power switch K
And one digital multimeter measuring circuit of interconnection and a display screen, the power control include a power control circuit
With a voltage detecting circuit, one end of the power switch K connects the positive pole of the battery BAT, and the other end connects described respectively
Power control circuit and voltage detecting circuit, the power control circuit is also connected with the digital multimeter measuring circuit, described
Voltage detecting circuit is additionally coupled to the power control circuit；The digital multimeter measuring circuit, voltage detecting circuit connect
It is connected to the battery BAT negative poles.
It is preferred that the voltage detecting circuit includes series circuit one, series circuit two and comparator IC2, the string
Connection circuit one is made up of the resistance R9 and voltage-stabiliser tube ZD being serially connected, the series circuit two by the resistance R10 that is serially connected and
Resistance R11 is formed；After the series circuit one and series circuit two are parallel with one another, one end is connected with power switch K, and the other end connects
Connect the negative pole of the battery BAT；The anode of the comparator IC2 is connected to the company between the resistance R10 and the resistance R11
On line, the negative terminal of the comparator IC2 is connected on the connecting line between the resistance R9 and voltage-stabiliser tube ZD, the comparator
IC2 output end connects the power control circuit.
It is preferred that the power control circuit includes resistance R12, triode Q1, resistance R13 and triode Q2；It is described
Resistance R12 one end connects the voltage detecting circuit, and the other end connects the base stage of the triode Q1, the triode Q1's
Colelctor electrode passes through the base stage of the resistance R13 connections triode Q2, the transmitting connection battery BAT of the triode Q1
Negative pole；The emitter stage of the triode Q2 connects the power switch K, and the colelctor electrode of the triode Q2 connects the numeral
Universal meter measuring circuit.
The utility model has the advantages that：
The 1st, voltage detecting circuit is set, current battery level state can be monitored in real time：When cell voltage is less than setting electricity
During pressure value, LOW signal is sent in time to power control circuit；When cell voltage is higher than setting magnitude of voltage, high ordinary mail number is sent
To power control circuit；
The 2nd, power control circuit is set, the working condition of digital multimeter measuring circuit can be controlled：When receiving Gao Ping
During signal, power control circuit conducting, digital multimeter measuring circuit works on power；When receiving LOW signal, power supply control
Circuit processed is closed, and digital multimeter measuring circuit can not work, and display screen extinguishes, and user can not operate digital multimeter；
To sum up, by setting voltage detecting circuit and voltage control circuit, it ensure that digital multimeter in use
Shown measured value is accurately and reliably numerical value, avoid cell voltage it is too low when, the measured value shown by digital multimeter
Inaccurate or mistake causes user to make erroneous judgement or injured.
Brief description of the drawings
Fig. 1 is the structural representation of prior art digital universal meter；
Fig. 2 is a kind of theory diagram of the power control of digital multimeter of the utility model；
Fig. 3 is a kind of circuit diagram of the power control of digital multimeter of the utility model.
Embodiment
The utility model is described in detail with specific embodiment below in conjunction with the accompanying drawings.
Fig. 2 and Fig. 3, a kind of power control of digital multimeter are referred to, the digital multimeter includes a battery
BAT, a power switch K and one digital multimeter measuring circuit of interconnection and a display screen, the power control bag
A power control circuit and a voltage detecting circuit are included, one end of the power switch K connects the positive pole of the battery BAT, separately
One end connects the power control circuit and voltage detecting circuit respectively, and the power control circuit is also connected with the digital versatile
Table measuring circuit, the voltage detecting circuit are additionally coupled to the power control circuit；The digital multimeter measuring circuit, electricity
Pressure detection circuit is connected to the battery BAT negative poles.
When power switch K is closed, magnitude of voltage V1 of the voltage detecting circuit monitoring battery BAT voltages higher than setting
When, it is conducting state that the voltage detecting circuit output signal, which controls the power control circuit, is surveyed for the digital multimeter
Measure circuit and working power is provided, make digital multimeter measuring circuit normal work, display screen normal measurements.
When power switch K is closed, magnitude of voltage V1 of the voltage detecting circuit monitoring battery BAT voltages less than setting
When, it is closed mode that the voltage detecting circuit output signal, which controls the power control circuit, the digital multimeter measurement
The working power of circuit is disconnected, and makes can not working for digital multimeter measuring circuit, and display screen extinguishes.
The magnitude of voltage V1 of the setting typically can be set as to ensure that digital multimeter shows correct measurement value most
Low voltage value.
Specifically, the voltage detecting circuit includes series circuit one, series circuit two and comparator IC2, the string
Connection circuit one is made up of the resistance R9 and voltage-stabiliser tube ZD being serially connected, the series circuit two by the resistance R10 that is serially connected and
Resistance R11 is formed；After the series circuit one and series circuit two are parallel with one another, one end is connected with power switch K, and the other end connects
Connect the negative pole of the battery BAT；The anode of the comparator IC2 is connected to the company between the resistance R10 and the resistance R11
On line, the negative terminal of the comparator IC2 is connected on the connecting line between the resistance R9 and voltage-stabiliser tube ZD, the comparator
IC2 output end connects the power control circuit.
The power control circuit includes resistance R12, triode Q1, resistance R13 and triode Q2；The resistance R12
One end connect the voltage detecting circuit, that is, the output end of the IC2, the other end connects the base of the triode Q1
Pole, the colelctor electrode of the triode Q1 pass through the base stage of the resistance R13 connections triode Q2, the hair of the triode Q1
Emitter-base bandgap grading connects the negative pole of the battery BAT；The emitter stage of the triode Q2 connects the power switch K, the triode Q2
Colelctor electrode connect the digital multimeter measuring circuit.
In physical circuit, voltage-stabiliser tube ZD provides a voltage stabilizing value, the magnitude of voltage V1 selection voltage-stabiliser tubes set as needed
ZD, therefore voltage stabilizing value is the magnitude of voltage V1 set.Resistance R10 and R11 form bleeder circuit, and partial pressure value V2, V2 is with battery
BAT voltages V+ is reduced and reduced.
When power switch K is closed, according to new battery BAT, partial pressure value V2 ＞ settings magnitude of voltage V1, comparator IC2 is defeated
Go out level VCFor high level, triode Q1 and Q2 are both turned on, and digital multimeter measuring circuit works on power, and LCD display is bright, number
Word universal meter normal work.According to used batteries：As battery BAT voltages constantly reduce, resistance R10 and resistance R11 partial pressure
Value V2 is also constantly reduced, because the voltage stabilizing value stabilization that voltage-stabiliser tube ZD is provided is constant, when cell voltage is reduced to setting value V1, point
Pressure value V2<Magnitude of voltage V1 is set, comparator IC2 output levels Vc is low level, triode Q1 cut-offs, triode Q2 cut-offs, is counted
The power supply of word universal meter measuring circuit is closed, and LCD display extinguishes, and digital multimeter can not work.
Embodiment of the present utility model is the foregoing is only, not thereby limits the scope of the claims of the present utility model, it is every
The equivalent structure or equivalent flow conversion made using the utility model specification and accompanying drawing content, or be directly or indirectly used in
Other related technical areas, similarly it is included in scope of patent protection of the present utility model.
Claims (3)
1. a kind of power control of digital multimeter, the digital multimeter include a battery BAT, a power switch K with
And it is connected with each other a digital multimeter measuring circuit and a display screen, it is characterised in that：The power control includes an electricity
Source control circuit and a voltage detecting circuit, one end of the power switch K connect the positive pole of the battery BAT, the other end point
The power control circuit and voltage detecting circuit are not connected, and the power control circuit is also connected with the digital multimeter measurement
Circuit, the voltage detecting circuit are additionally coupled to the power control circuit；The digital multimeter measuring circuit, voltage detecting
Circuit is connected to the battery BAT negative poles.
A kind of 2. power control of digital multimeter according to claim 1, it is characterised in that：The voltage detecting
Circuit includes series circuit one, series circuit two and comparator IC2, the series circuit one by the resistance R9 that is serially connected and
Voltage-stabiliser tube ZD is formed, and the series circuit two is made up of the resistance R10 and resistance R11 being serially connected；The He of series circuit one
After series circuit two is parallel with one another, one end is connected with power switch K, and the other end connects the negative pole of the battery BAT；The comparison
Device IC2 anode is connected on the line between the resistance R10 and the resistance R11, the negative terminal connection of the comparator IC2
On connecting line between the resistance R9 and voltage-stabiliser tube ZD, the output end of the comparator IC2 connects the power supply electricity
Road.
A kind of 3. power control of digital multimeter according to claim 1, it is characterised in that：The power supply
Circuit includes resistance R12, triode Q1, resistance R13 and triode Q2；One end of the resistance R12 connects the voltage inspection
Slowdown monitoring circuit, the other end connect the base stage of the triode Q1, and the colelctor electrode of the triode Q1 passes through the resistance R13 connections institute
Triode Q2 base stage is stated, the emitter stage of the triode Q1 connects the negative pole of the battery BAT；The transmitting of the triode Q2
Pole connects the power switch K, and the colelctor electrode of the triode Q2 connects the digital multimeter measuring circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721135013.5U CN207181498U (en) | 2017-09-06 | 2017-09-06 | A kind of power control of digital multimeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721135013.5U CN207181498U (en) | 2017-09-06 | 2017-09-06 | A kind of power control of digital multimeter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207181498U true CN207181498U (en) | 2018-04-03 |
Family
ID=61742829
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721135013.5U Expired - Fee Related CN207181498U (en) | 2017-09-06 | 2017-09-06 | A kind of power control of digital multimeter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207181498U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108732401A (en) * | 2018-07-04 | 2018-11-02 | 优利德科技(中国)股份有限公司 | A kind of multimeter measurement accuracy prior-warning device, method and multimeter |
-
2017
- 2017-09-06 CN CN201721135013.5U patent/CN207181498U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108732401A (en) * | 2018-07-04 | 2018-11-02 | 优利德科技(中国)股份有限公司 | A kind of multimeter measurement accuracy prior-warning device, method and multimeter |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20180514 Address after: 363000 Building 1, Jintang road science and Technology Park, Jinfeng Economic Development Zone, Xiangcheng District, Zhangzhou, Fujian Patentee after: ZHANGZHOU YUSHAN ELECTRONIC MANUFACTURING CO.,LTD. Address before: 363000 Dongfang Science and Technology Industrial Park, Jintang Road, Jinfeng Economic Development Zone, Xiangcheng District, Zhangzhou, Fujian, China Patentee before: ZHANGZHOU EASTERN INTELLIGENT METER Co.,Ltd. |
|
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20180403 |