CN104834241B - Digital input circuit - Google Patents
Digital input circuit Download PDFInfo
- Publication number
- CN104834241B CN104834241B CN201510248091.5A CN201510248091A CN104834241B CN 104834241 B CN104834241 B CN 104834241B CN 201510248091 A CN201510248091 A CN 201510248091A CN 104834241 B CN104834241 B CN 104834241B
- Authority
- CN
- China
- Prior art keywords
- module
- input circuit
- digital input
- triode
- switch control
- 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.)
- Active
Links
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
Abstract
The invention discloses digital input circuit, biasing module, isolation module, current limliting module, switch control module, drop-down module, the first filtration module and the second filtration module, when input voltage is higher than predeterminated voltage, the output of digital input circuit is closed by switch control module, and external high pressure is isolated by isolation module, prevent from damaging late-class circuit, so as to improve the performance of electronic product, reduce maintenance cost.
Description
Technical field
The present invention relates to circuit design field, more particularly to digital input circuit.
Background technology
In commercial Application, most of electronic component all has certain requirement to operating voltage, if brownout is electric
Subcomponent can not start work, and overtension can burn out electronic device.The conventional voltage of digital circuit is 3.3V or 5V, outside
The operating voltage of portion's sensor can reach 24V.The signal of sensor will enter internal digital circuit, it is necessary to enter turning for line level
Change, if input voltage is too high, these electronic components can be damaged.Photoelectrical coupler will typically now be used to carry out signal level
Conversion, but optocoupler has that volume is big, cost is high, slow-footed shortcoming.Thus prior art could be improved and improve.
The content of the invention
In view of in place of above-mentioned the deficiencies in the prior art, it is an object of the invention to provide digital input circuit, can limit height
Pressure input, prevent from damaging late-class circuit.
In order to achieve the above object, this invention takes following technical scheme：
A kind of digital input circuit, for protecting late-class circuit not damaged by high pressure, it includes：
For providing the biasing module of bias current；
For isolating the isolation module of digital input circuit described in high input voltage；
Current limliting module for current limliting；
For the switch control module closed when input voltage is higher than predeterminated voltage；
Ensure that digital input circuit exports low level drop-down module when being closed for switch control module；
The first filtration module and the second filtration module for filtering interference signals；
One end of the isolation module connected for the input of digital input circuit, by biasing module COM+ feeder ears,
It is grounded also by the second filtration module, the other end of isolation module passes through the first of the current limliting module connecting valve control module
End and one end of the first filtration module, the other end of first filtration module connect VCC with the second end of switch control module
Feeder ear, the 3rd end of switch control module are the output end of digital input circuit, the connection late-class circuit, also pass through drop-down
Module ground.
In described digital input circuit, the switch control module includes triode and first resistor, first electricity
One end of resistance is first end, the base stage of connecting triode of switch control module, and the other end connection VCC of first resistor powers
End；The transmitting of the triode integrates the second end as switch control module, the connection VCC feeder ears, the collection of the triode
Electrode is the 3rd end of switch control module.
In described digital input circuit, the isolation module includes diode, and the current limliting module includes second resistance,
The base stage of one end connecting triode of the second resistance and one end of the first filtration module, the other end connection two of second resistance
The positive pole of pole pipe, the negative pole of the diode are the input of digital input circuit.
In described digital input circuit, first filtration module includes the first electric capacity, one end of first electric capacity
The base stage of connecting triode and one end of second resistance, the other end connection VCC feeder ears of first electric capacity.
In described digital input circuit, second filtration module includes the second electric capacity, one end of second electric capacity
Connect the negative pole of diode, one end ground connection of the second electric capacity.
In described digital input circuit, the biasing module includes 3rd resistor, one end connection of the 3rd resistor
COM+ feeder ears, the negative pole of the other end connection diode of the 3rd resistor.
In described digital input circuit, the drop-down module includes the 4th resistance, one end connection of the 4th resistance
The colelctor electrode of triode, the other end ground connection of the 4th resistance.
Described digital input circuit, include the indicating module of the working condition for designation number input circuit, institute
The 3rd end for stating switch control module is also grounded by indicating module.
In described digital input circuit, the indicating module includes LED and the 5th resistance, the positive pole connection of the LED
The colelctor electrode of the triode, the negative pole of the LED pass through the 5th resistance eutral grounding.
Compared to prior art, digital input circuit provided by the invention includes：Biasing module, isolation module, current limliting mould
Block, switch control module, drop-down module, the first filtration module and the second filtration module, when input voltage is higher than predeterminated voltage,
The output of digital input circuit is closed by switch control module, and is isolated external high pressure by isolation module, prevents from damaging rear class
Circuit, so as to improve the performance of electronic product, reduce maintenance cost.
Brief description of the drawings
Fig. 1 is the circuit diagram of digital input circuit provided in an embodiment of the present invention.
Embodiment
The present invention provides digital input circuit, to make the purpose of the present invention, technical scheme and effect clearer, clear and definite,
The present invention is described in more detail for the embodiment that develops simultaneously referring to the drawings.It should be appreciated that specific embodiment described herein
Only to explain the present invention, it is not intended to limit the present invention.
Referring to Fig. 1, digital input circuit provided by the invention includes：Biasing module 10, isolation module 20, current limliting module
30th, switch control module 40, drop-down module 50, the first filtration module 60 and the second filtration module 70, the isolation module 20
One end connects COM+ feeder ears, also by the second filtration module 70 for the input of digital input circuit, by biasing module 10
Ground connection, the other end of isolation module 20 are filtered by the first end of the connecting valve control module 40 of current limliting module 30 and first
One end of module 60, the other end of the first filtration module 60 connect VCC feeder ears with the second end of switch control module 40, switch
3rd end of control module 40 is the output end of digital input circuit, the connection late-class circuit, also connect by pulling down module 50
Ground.
Wherein, the first filtration module 60 and the second filtration module 70 are used for filtering interference signals, specifically for filtering out high frequency
Signal interference.The switch control module 40 is used to close the defeated of digital input circuit when input voltage is higher than predeterminated voltage
Go out, so as to protect late-class circuit（Such as single-chip microcomputer）, the isolation module 20 is for isolating digital input circuit described in high input voltage.
The biasing module 10 is used to provide bias current, strengthens the antijamming capability of digital input circuit, and current limliting module 30 is used to open
The input current for closing control module 40 carries out current limliting, prevents switch control module 40 from damaging.Module 50 is pulled down to be used to switch control
Module 40 ensures that digital input circuit exports low level when closing.In the present embodiment, the high pressure is the electricity more than predeterminated voltage
Pressure.
Please continue to refer to Fig. 1, the switch control module 40 includes triode Q1 and first resistor R1, the first resistor
R1 one end is first end, the connecting triode Q1 base stage of switch control module 40, and the first resistor R1 other end connects VCC
Feeder ear；The transmitting of the triode Q1 integrates the second end as switch control module 40, connects the VCC feeder ears, and described three
3rd end of pole pipe Q1 current collection extremely switch control module 40.The triode Q1 is PNP triode, the first resistor R1
For triode Q1 base pull-up resistor.
Wherein, the model S8550 of the triode, the resistance of first resistor is 1-100 kilohms.Certainly, other
In embodiment, the NPN triode of other models, or other types of switching tube or component can be also used to replace the PNP tri-
Pole pipe, the invention is not limited in this regard.
Triode Q1 can improve antijamming capability, and by taking 5V TTL circuits as an example, electric characteristic is：Input voltage is in 0.8V
For low level, more than 2.4V is high level, is ended when triode Q1 base stage is low level when conducting, high level.It is assumed that VCC
The voltage of feeder ear is 5V, when input signal is 0V, if generating 2V interference on transmission line, if without using triode,
Then erroneous judgement occurs in logical device, has now used triode Q1, can effectively judge, as long as external input voltage is less than 4V（Allusion quotation
Type）Low level will be judged as.
The isolation module 20 includes diode D1, and the current limliting module 30 includes second resistance R2, the diode
Model IN4148 or other models, the resistance of second resistance is 1-100 kilohms.One end connection of the second resistance R2
One end of triode Q1 base stage and the first filtration module 60, second resistance R2 other end connection diode D1 positive pole, institute
The negative pole for stating diode D1 is the input of digital input circuit.The diode D1 is one way conducting device, works as input voltage
During higher than predeterminated voltage, diode D1 cut-offs.The second resistance R2 is triode Q1 input resistances, for limiting triode Q1
Base current.
Please continue to refer to Fig. 1, one end that first filtration module 60 includes the first electric capacity C1, the first electric capacity C1 connects
Connect VCC feeder ears, the other end connecting triode Q1 base stage of the first electric capacity C1 and second resistance R2 one end.
Accordingly, second filtration module 70 includes the second electric capacity C2, the second electric capacity C2 one end two poles of connection
Pipe D1 negative pole, the second electric capacity C2 one end ground connection.
Wherein, the capacitance of the first electric capacity C1 is 0.01-10uF, and the second electric capacity C2 capacitance is 100-2000pF.It is defeated
Enter signal and first filter out high frequency letter after the second electric capacity C2 progress input filters remove high-frequency signal, then by the first electric capacity C1
Number.
Please continue to refer to Fig. 1, one end that the biasing module 10 includes 3rd resistor R3, the 3rd resistor R3 connects
COM+ feeder ears, the other end connection diode D1 of 3rd resistor E3 negative pole.The drop-down module 50 includes the 4th electricity
Hinder R4, one end connecting triode Q1 of the 4th resistance R4 colelctor electrode, the 4th resistance R4 other end ground connection.
Wherein, COM+ feeder ears are external voltage power supply, such as 24V, 48V.The resistance of the 3rd resistor R3 is 0.3-1
Kilohm, for providing bias current, the antijamming capability of accentuator.The resistance of the 4th resistance R4 is 1-100 kilo-ohms
Nurse, for ensure triode Q1 cut-off when, triode Q1 output low level.
Further, digital input circuit also includes the indicating module of the working condition for designation number input circuit
80, the 3rd end of the switch control module 40 is also grounded by indicating module 80.Wherein, the indicating module 80 includes LED
D2 and the 5th resistance R5, the LED D2 positive pole connect the colelctor electrode of the triode Q1, and the negative pole of the LED D2 passes through
5th resistance R5 is grounded.When digital input circuit is less than predeterminated voltage, the indicating module 80 starts, i.e. triode Q1 conductings
When, the LED D2 are lighted, and when triode Q1 ends, LED D2 extinguish.
In order to be better understood from the present invention, digital input circuit provided by the invention is carried out specifically below in conjunction with Fig. 1
It is bright：
When the voltage of input signal is less than predeterminated voltage, triode Q1 conductings, input signal inputs at the IN in Fig. 1
Described digital input circuit, most of high-frequency interferencing signal is removed through the second electric capacity C2 filtering, then through diode D1 and second
After resistance R2 current limlitings, being filtered through the first electric capacity C1 and remove high-frequency signal, stable signal is exported by triode Q1 colelctor electrode,
Now LED D2 just extremely high level and light.
When the voltage of input signal is higher than predeterminated voltage, triode Q1 cut-offs, now diode D1 is also switched off, diode
D1 reliably prevents external input signal from inputting digital input circuit, when the first resistor R1 ensures diode D1 cut-offs, three poles
Pipe Q1 is reliably closed, and also the first electric capacity C1 is discharged, the rapid voltage for reducing the first electric capacity C1 both ends.
Above-mentioned analysis understands that the voltage of input signal allows maximum to forward direction to allow maximum to be negative, export as 0 ~
VCC, realization makes external high voltage signal not enter logic region, so as to be embodied as the protection of circuit.
Therefore, when input signal is higher than VCC, this circuit output signal is 0V, when input signal is less than VCC-Vb, exports and is
VCC.Wherein, Vb is the voltage drop of diode and triode, about 0.3V ~ 1V.The present invention realizes input letter by triode Q1
Number there is the discrimination level of determination, make the reliable low and high level of digital input circuit.The digital input circuit of the present invention can be applied extremely
0 ~ 24V is inputted, in the digital circuit for exporting 0 ~ 5V, and can be by suitably selecting diode D1,3rd resistor R3 and the second electricity
Hold C2 specification, input voltage can be allow to reach -100V ~+100V.
It is understood that for those of ordinary skills, can be with technique according to the invention scheme and its hair
Bright design is subject to equivalent substitution or change, and all these changes or replacement should all belong to the guarantor of appended claims of the invention
Protect scope.
Claims (7)
- A kind of 1. digital input circuit, for protecting late-class circuit not damaged by high pressure, it is characterised in that including：For providing the biasing module of bias current；For isolating the isolation module of digital input circuit described in high input voltage；Current limliting module for current limliting；For the switch control module closed when input voltage is higher than predeterminated voltage；Ensure that digital input circuit exports low level drop-down module when being closed for switch control module；The first filtration module and the second filtration module for filtering interference signals；One end of the isolation module connects COM+ feeder ears for the input of digital input circuit, by biasing module, also led to Cross the second filtration module ground connection, the other end of isolation module by the first end of the current limliting module connecting valve control module and One end of first filtration module, the other end of first filtration module and the second end of switch control module connect VCC power supplies End, the 3rd end of switch control module is the output end of digital input circuit, the connection late-class circuit, also by pulling down module Ground connection；The switch control module includes triode and first resistor, and the triode is PNP triode, the first resistor One end be switch control module first end, the base stage of connecting triode, first resistor the other end connection VCC feeder ears； The transmitting of the triode extremely the second end of switch control module, the connection VCC feeder ears, the colelctor electrode of the triode For the 3rd end of switch control module；The isolation module includes diode, and the current limliting module includes second resistance, and described The base stage of one end connecting triode of two resistance and one end of the first filtration module, the other end connection diode of second resistance Positive pole, the negative pole of the diode are the input of digital input circuit；The diode is one way conducting device, when input electricity When pressure is higher than predeterminated voltage, diode cut-off.
- 2. digital input circuit according to claim 1, it is characterised in that first filtration module includes the first electricity Hold, the base stage of one end connecting triode of first electric capacity and one end of second resistance, the other end of first electric capacity connects Connect VCC feeder ears.
- 3. digital input circuit according to claim 2, it is characterised in that second filtration module includes the second electricity Hold, the negative pole of one end connection diode of second electric capacity, one end ground connection of the second electric capacity.
- 4. digital input circuit according to claim 3, it is characterised in that the biasing module includes 3rd resistor, institute State one end connection COM+ feeder ears of 3rd resistor, the negative pole of the other end connection diode of the 3rd resistor.
- 5. digital input circuit according to claim 4, it is characterised in that the drop-down module includes the 4th resistance, institute State the colelctor electrode of one end connecting triode of the 4th resistance, the other end ground connection of the 4th resistance.
- 6. digital input circuit according to claim 4, it is characterised in that also include for designation number input circuit The indicating module of working condition, the 3rd end of the switch control module are also grounded by indicating module.
- 7. digital input circuit according to claim 6, it is characterised in that the indicating module includes the electricity of LED and the 5th Resistance, the positive pole of the LED connect the colelctor electrode of the triode, and the negative pole of the LED passes through the 5th resistance eutral grounding.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510248091.5A CN104834241B (en) | 2015-05-15 | 2015-05-15 | Digital input circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510248091.5A CN104834241B (en) | 2015-05-15 | 2015-05-15 | Digital input circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104834241A CN104834241A (en) | 2015-08-12 |
| CN104834241B true CN104834241B (en) | 2018-01-23 |
Family
ID=53812193
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510248091.5A Active CN104834241B (en) | 2015-05-15 | 2015-05-15 | Digital input circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104834241B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105867212A (en) * | 2016-03-24 | 2016-08-17 | 航天科技控股集团股份有限公司 | Wake-up circuit for converting low-level signal to high-level signal |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101867168A (en) * | 2010-05-21 | 2010-10-20 | 海洋王照明科技股份有限公司 | Power protecting circuit and LED lamp |
| CN103855980A (en) * | 2012-11-30 | 2014-06-11 | 西安智海电力科技有限公司 | Output protected high-performance power conversion circuit |
| CN104218521A (en) * | 2013-05-30 | 2014-12-17 | 深圳市海洋王照明工程有限公司 | A low voltage protection circuit |
| CN204613635U (en) * | 2015-05-15 | 2015-09-02 | 深圳市施美森科技有限公司 | A kind of digital input circuit |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19958501A1 (en) * | 1999-11-30 | 2001-06-07 | Mannesmann Ag | Lifting device to increase the performance of a handling device for ISO containers |
| KR101822067B1 (en) * | 2010-10-28 | 2018-03-08 | 페어차일드코리아반도체 주식회사 | Led emitting device |
-
2015
- 2015-05-15 CN CN201510248091.5A patent/CN104834241B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101867168A (en) * | 2010-05-21 | 2010-10-20 | 海洋王照明科技股份有限公司 | Power protecting circuit and LED lamp |
| CN103855980A (en) * | 2012-11-30 | 2014-06-11 | 西安智海电力科技有限公司 | Output protected high-performance power conversion circuit |
| CN104218521A (en) * | 2013-05-30 | 2014-12-17 | 深圳市海洋王照明工程有限公司 | A low voltage protection circuit |
| CN204613635U (en) * | 2015-05-15 | 2015-09-02 | 深圳市施美森科技有限公司 | A kind of digital input circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104834241A (en) | 2015-08-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103605017A (en) | Detection method of vehicle switch quantity signal | |
| CN110018726A (en) | The main website machine device for providing power supply simultaneously using two lines bus and being communicated | |
| CN205068033U (en) | Detection control circuit of water level perception device | |
| CN104407687A (en) | Reset circuit | |
| CN104834241B (en) | Digital input circuit | |
| CN104753327B (en) | Switching Power Supply | |
| CN103888871B (en) | Wire control device used for earphone and earphone | |
| CN206099296U (en) | Overvoltage crowbar and electronic equipment | |
| CN106406816A (en) | An interface circuit used for firmware upgrade and an intelligent apparatus | |
| CN204613635U (en) | A kind of digital input circuit | |
| CN103108081A (en) | Subscriber identity module (SIM) card detection control device of mobile terminal | |
| CN206096223U (en) | Buffer circuit is gathered to wide voltage switch volume | |
| CN106199458A (en) | A kind of power sense circuit | |
| CN104092268B (en) | A kind of process circuit of the precharge cell voltage of mobile terminal | |
| CN204873311U (en) | Wide voltage switching signal acquisition circuit of elevator | |
| CN202998317U (en) | Video matrix self-adaption video ring circuit | |
| CN103401510B (en) | A kind of power amplifier of band warm connection function | |
| CN209805433U (en) | Charging circuit and device | |
| CN207133815U (en) | A kind of video card | |
| CN207625285U (en) | Protection circuit with lag function and power supply system | |
| CN208863013U (en) | A kind of HDMI input hot plug detection circuit | |
| CN207766525U (en) | Sound equipment with power supply protection function | |
| CN102621917B (en) | Method and device for preventing situation of carrying out hot plugging on ECU (electronic control unit) connectors | |
| CN207516708U (en) | A kind of optical filter switching circuit | |
| CN205721154U (en) | A kind of food processing machine control circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| EXSB | Decision made by sipo to initiate substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20210114 Address after: 518101 1603a, building 3, COFCO Chuangzhi factory, 67 District, Xin'an street, Bao'an District, Shenzhen City, Guangdong Province Patentee after: Shenzhen Gao Chuan Automation Technology Co.,Ltd. Address before: 518043 B block 1802, Shandong mansion, Nanhai Road, Nanshan District, Shenzhen, Guangdong. Patentee before: SHENZHEN SMOOTH CONTROL TECHNOLOGY Ltd. |
|
| CP02 | Change in the address of a patent holder | ||
| CP02 | Change in the address of a patent holder |
Address after: 518101 Room 401, building a, Xinzheng factory, 71 District, Xingdong community, Xin'an street, Bao'an District, Shenzhen City, Guangdong Province Patentee after: Shenzhen Gao Chuan Automation Technology Co.,Ltd. Address before: 518101 1603a, building 3, COFCO Chuangzhi factory, 67 District, Xin'an street, Bao'an District, Shenzhen City, Guangdong Province Patentee before: Shenzhen Gao Chuan Automation Technology Co.,Ltd. |