CN110365322A - A kind of digital output card - Google Patents
A kind of digital output card Download PDFInfo
- Publication number
- CN110365322A CN110365322A CN201910585724.XA CN201910585724A CN110365322A CN 110365322 A CN110365322 A CN 110365322A CN 201910585724 A CN201910585724 A CN 201910585724A CN 110365322 A CN110365322 A CN 110365322A
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- China
- Prior art keywords
- output
- circuit
- mos pipe
- power supply
- power mos
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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
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
- G05B19/0423—Input/output
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F13/00—Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units
- G06F13/38—Information transfer, e.g. on bus
- G06F13/382—Information transfer, e.g. on bus using universal interface adapter
- G06F13/385—Information transfer, e.g. on bus using universal interface adapter for adaptation of a particular data processing system to different peripheral devices
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/08—Modifications for protecting switching circuit against overcurrent or overvoltage
- H03K17/082—Modifications for protecting switching circuit against overcurrent or overvoltage by feedback from the output to the control circuit
- H03K17/0822—Modifications for protecting switching circuit against overcurrent or overvoltage by feedback from the output to the control circuit in field-effect transistor switches
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Emergency Protection Circuit Devices (AREA)
- Dc-Dc Converters (AREA)
Abstract
The embodiment of the present invention provides a kind of digital output card, which includes: overcurrent self-locking protection circuit and power MOS pipe switching circuit；Power MOS pipe is equipped in the power MOS pipe switching circuit, the switch order for exporting according to processor, by the conducting and disconnection of the source electrode and drain electrode of power MOS pipe, the on-off of control output power supply realizes digital output；The overcurrent self-locking protects circuit, for disconnecting the on state of the source electrode and drain electrode of power MOS pipe when the electric current of digital output is greater than preset threshold.Circuit is protected by overcurrent self-locking, when the electric current of digital output is greater than preset threshold, disconnects the on state of the source electrode and drain electrode of power MOS pipe, to realize overcurrent protection, and can be protected circuit that maximum cut-off current is set according to overcurrent self-locking.
Description
Technical field
The present invention relates to electronic information technical field more particularly to a kind of digital output cards.
Background technique
Digital output card receives processor as train network control system important component, by bus communication
The instruction of unit externally exports on-off model or driving electric switch equipment.Digital output card is in bullet train, subway
It is widely used in network control system etc. all kinds of trains.Reliability, the stability of digital output card directly influence whole
The reliability of a train network control system output executing mechanism is most important to safe train operation.Therefore, as train net
The important component of network control system, digital output card need very high reliability and safety.
Stability, the reliability for ensuring digital output card need to accomplish output isolation, overcurrent-overvoltage protection, output
The safety measures such as status monitoring.The switching mode of existing digital output card mainly has: power MOS pipe, relay (contact
Formula).Power MOS pipe switch, reaction speed is fast, but can not cope with the overcurrent protection of the larger situation of output electric current.Relay is opened
It closes, output electric current is big, but can not achieve output overcurrent protection, and reaction speed is slightly slow.
Current digital output card can not preferably realize overcurrent protection when output electric current is larger.
Summary of the invention
To solve the above-mentioned problems, the embodiment of the present invention provides a kind of digital output card.
In a first aspect, the embodiment of the present invention provides a kind of digital output card, comprising: overcurrent self-locking protects circuit and function
Rate metal-oxide-semiconductor switching circuit；Power MOS pipe, the switch for exporting according to processor are equipped in the power MOS pipe switching circuit
Instruction, by the conducting and disconnection of the source electrode and drain electrode of power MOS pipe, the on-off of control output power supply realizes digital quantity
Output；The overcurrent self-locking protects circuit, for disconnecting power MOS pipe when the electric current of digital output is greater than preset threshold
Source electrode and drain electrode on state.
Digital output card provided in an embodiment of the present invention protects circuit by overcurrent self-locking, when digital output
When electric current is greater than preset threshold, the on state of the source electrode and drain electrode of power MOS pipe is disconnected, to realize overcurrent protection, and can
Protect circuit that maximum cut-off current is set according to overcurrent self-locking.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is this hair
Bright some embodiments for those of ordinary skill in the art without creative efforts, can be with root
Other attached drawings are obtained according to these attached drawings.
Fig. 1 is digital output card structure chart provided in an embodiment of the present invention；
Fig. 2 be another embodiment of the present invention provides digital output card structure chart；
Fig. 3 is the digital output card structure chart that further embodiment of this invention provides；
Fig. 4 is digital output card circuit diagram provided in an embodiment of the present invention.
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention
In attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is
A part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art
Every other embodiment obtained without creative efforts, shall fall within the protection scope of the present invention.
Fig. 1 is digital output card structure chart provided in an embodiment of the present invention, as shown in Figure 1, the embodiment of the present invention mentions
For a kind of digital output card, comprising: including output power supply 101, overcurrent self-locking protection circuit 102 and power MOS pipe
Switching circuit 103.
Power MOS pipe is equipped in power MOS pipe switching circuit 103, the switch order for exporting according to processor passes through
The conducting and disconnection of the source electrode and drain electrode of power MOS pipe, the on-off of control output power supply, realize digital output.Overcurrent
Self-locking protective circuit 102 is used to disconnect the source electrode and drain electrode of power MOS pipe when the electric current of digital output is greater than preset threshold
On state.
When digital quantity board exports digital quantity signal, processor sends switching signal to power MOS pipe switching circuit 102
(Output command), the level of the switching signal to be connected between the source electrode and drain electrode of power MOS pipe, to realize defeated
The level signal of power supply can be exported in output end out, realize the high level output of digital quantity signal.
When digital quantity board does not export digital quantity signal, processor is no longer opened to the transmission of power MOS pipe switching circuit 102
OFF signal, so that the source electrode and drain electrode of power MOS pipe is separated, to export the level signal of power supply not defeated
Outlet output, digital quantity signal is low level.
When digital quantity board exports digital quantity signal, if output channel short-circuited outside, the electricity of digital output
Stream just will increase, and overcurrent self-locking protects circuit 102 that a current threshold is arranged according to the element characteristics of circuit, when electric current increase is super
When crossing the preset threshold, then change the on state between the source electrode and drain electrode of power MOS pipe to disconnect, to realize that overcurrent is protected
Shield.Overcurrent self-locking protects circuit, corresponding preset threshold can be arranged, so as to set as needed according to the electrical characteristic of element
Determine maximum current value.
Digital output card provided in an embodiment of the present invention protects circuit by overcurrent self-locking, when digital output
When electric current is greater than preset threshold, the on state of the source electrode and drain electrode of power MOS pipe is disconnected, to realize overcurrent protection, and can
Protect circuit that maximum cut-off current is set according to overcurrent self-locking.
Content based on the above embodiment, as a kind of alternative embodiment, it includes first that overcurrent self-locking, which protects circuit 102,
Road and second branch；The first branch, for connecting the source electrode and output power supply 101 of the power MOS pipe；Described
Two branches, for when the electric current of digital output is less than preset threshold, making the grid and output power supply electricity of the power MOS pipe
Source 101 disconnects, and when the electric current of digital output is greater than preset threshold, makes the grid and output power supply electricity of the power MOS pipe
Source 103 is connected.
When the electric current of digital output is less than preset threshold, source electrode and the output power supply of power MOS pipe normally connect
It connects, by state, normally exports digital quantity signal between power MOS pipe source electrode and drain electrode.In this case, power MOS
The grid and output power supply 101 of pipe are to disconnect.When the electric current of output channel short-circuited outside, digital output can be greater than
Preset threshold, the connection status between the grid and output power supply of power MOS pipe, by second branch by disconnection before
Become being connected, so that the grid of power MOS pipe also receives the level signal of output power supply.At this point, the source of power MOS pipe
Voltage between pole and grid reduces, so that power MOS is turned off, realizes output channel and automatically shuts down guarantor in output overcurrent
Protective function.
Digital output card provided in an embodiment of the present invention is used for by second branch when the electric current of digital output is small
When preset threshold, disconnect the grid of the power MOS pipe and output power supply, when the electric current of digital output is greater than in advance
If when threshold value, the grid of the power MOS pipe is connected with output power supply, to fast and accurately realize overcurrent guarantor
Shield.
Content based on the above embodiment, as a kind of alternative embodiment, the first branch is in parallel with the second branch, institute
Stating the first branch includes at least one resistance, and the second branch includes at least one triode.
Specifically, when output channel short-circuited outside, the electric current of the first branch increases, the electricity of resistance in the first branch
Pressure increases, so that the triode ON in second branch in parallel, realizes between output power supply and power MOS pipe grid
Connection, to reduce the voltage of power MOS pipe grid and source electrode, the on state of the source electrode and drain electrode of power MOS pipe becomes
It disconnects, to realize overcurrent protection.
Content based on the above embodiment, as a kind of alternative embodiment, which further includes output state
Observation circuit, the output state observation circuit are connect with output end, after the output state Monitoring instruction for receiving processor,
The level signal of output end is obtained, and the level signal of the output end is fed back into processor.
Specifically, which is arranged in output end, has input connection and output to connect respectively with processor
It connects, input connection receives the output state Monitoring instruction (checkcomand) of processor, which may include
One triode, when output end has level signal, the triode ON, to form access in status monitoring circuit, and will
Corresponding level signal is connected by the output of status monitoring circuit preprocessor, sends the feedback signal (Output of output state
Feedback processor) is given.By output state observation circuit, after the output state Monitoring instruction for receiving processor, obtain defeated
The level signal of outlet, and the level signal of the output end is fed back into processor, to realize the signal detection of output end.
Content based on the above embodiment, as a kind of alternative embodiment, which further includes power supply
Down Monitor Unit circuit, the power supply down Monitor Unit circuit, for being input in the level signal of the output power supply
Before the overcurrent self-locking protection circuit, the power supply state of the output power supply is obtained, and feeds back to processor, is conducive to
Realize various alarms and counter-measure.
Power supply down Monitor Unit circuit is identical as above-mentioned outputs state detection circuit theory, can refer to above-mentioned output state
Detection circuit.By power supply down Monitor Unit circuit, first time feedback processor, is conducive to reality after power supply power down
Existing various alarms and counter-measure.
Content based on the above embodiment, as a kind of alternative embodiment, the digital output module is in the power MOS pipe
The output end of switching circuit, is equipped with output terminal protecting circuit, and the output terminal protecting circuit is defeated for realizing the digital signal
Over-voltage and anti-reverse protection out.
Output terminal protecting circuit is used for output over-voltage protection, and prevents wrong external equipment and cause reverse breakdown line
Road can be realized by setting diode.
Content based on the above embodiment, as a kind of alternative embodiment, the digital output module is in the power MOS pipe
The output end of switching circuit is additionally provided with output state LED indicating circuit, for showing the output state of output high level.
In level output end, output state LED indicating circuit is for showing output high level state.Work as digital output
LED light is bright when for high level, and LED light is gone out when digital output is low level, to realize intuitive display at this time
Level state.
Content based on the above embodiment, as a kind of alternative embodiment, which further includes board temperature
Detection circuit, for monitoring the temperature of board.
Content based on the above embodiment, as a kind of alternative embodiment, which further includes voltage regulator circuit,
For stablizing the voltage signal for exporting power supply output.
Content based on the above embodiment, as a kind of alternative embodiment, the power MOS pipe of the digital output module is switched
Circuit, output state observation circuit, power supply down Monitor Unit circuit and board processor do electrical isolation processing.The present invention
The electrical isolation of embodiment, including but not limited to, light-coupled isolation and Magnetic isolation.Pass through power MOS pipe switching circuit, output state
Observation circuit, power supply down Monitor Unit circuit and board processor do electrical isolation processing, thus avoid processor by
Electrical damage.
Fig. 2 be another embodiment of the present invention provides digital output card structure chart, as shown in Figure 2.Processor 109 is logical
It crosses Magnetic isolation device and output switch order is sent to turning on and off for the realization output circuit of power MOS pipe switching circuit 103.
Power supply 101 is exported by voltage regulator circuit 108, overcurrent self-locking protection circuit 102, power MOS pipe switching circuit 103 and output
Outputs level signals after terminal protecting circuit 106.
Power supply power-fail detection circuit 105 obtains the level state of output power supply 101 after voltage regulator circuit 108, and
Status information is sent to processor 109 by optocoupler, processor 109 confirms whether power supply falls according to status information
Electricity.In level output end, outputs state detection circuit 104 obtains output level status and is sent to processor by optocoupler
109, processor 109 confirms whether output level is normal according to status information, can detect output short-circuit failure.
In level output end, output state LED indicating circuit 107 is for showing output high level state；It is exported in level
End, overvoltage protection of the output terminal protecting circuit 106 for output, and prevent wrong external equipment and cause reverse breakdown line
Road.
Fig. 3 is the digital output card structure chart that further embodiment of this invention provides, as shown in figure 3, digital output
Board is communicated by RS485 bus with other function board realization on backboard, and obtaining direct current 5V power supply from backboard is processor
The power supply of circuit, isolation circuit processor side.Output circuit has two groups of totally 8 tunnel output channels, and every 4 tunnel output channel is one
Group is often assembled with and exports power supply all the way, and two groups mutually isolated.Output order, the outputs state detection letter of each output channel
Breath and power supply status monitoring information are interacted by Magnetic isolation device, light isolation device and processor circuit.
Fig. 4 is digital output card circuit diagram provided in an embodiment of the present invention.Wherein, current-limiting resistance R1 and capacitor
C1, resistance R2, resistance R3, triode Q2, triode Q3 constitute output overcurrent self-locking protective circuit.Resistance R6, resistance R8, resistance
R10, triode Q4, triode Q5 constitute the ON-OFF control circuit of power MOS pipe Q1, it is ensured that turn off output when output overcurrent in time
Channel.Power MOS pipe Q1, zener diode V1, resistance R4 constitute output executing circuit.ON-OFF control circuit and output execute electricity
Road collectively forms power MOS pipe switching circuit.Light-emitting diode LED 1, resistance R7, resistance R9, resistance R11, metal-oxide-semiconductor Q6 are constituted
Output state indicating circuit；Resistance R12, resistance R13, resistance R14, resistance R15, power resistor R16, resistance R17, resistance R19,
Capacitor C7, capacitor C8, diode D2, zener diode D3, zener diode D4, triode Q7, Q8 form outputs state detection
Circuit, wherein selected by output level value (i.e. output power supply size) difference, power resistor R16 and zener diode D3
Parameter also accordingly change.
Processor sends output control instruction (Output_Command) to output switch control by Magnetic isolation chip U1
Circuit, so that VCC, R1, R4, V1, Q5, R10, GND line are connected, S, G pole tension of final power MOS pipe Q1 is stablized in pressure stabilizing
The pressure stabilizing value of diode V1, power MOS pipe Q1 is open-minded, and VCC exports digital quantity level signal (Output_ by R1, Q1, D1
Signal).For preventing external interface misconnection input signal, TVS1's output end D1 releases for realizing inductive load current.
When output channel short-circuited outside, the electric current for flowing through current-limiting circuit R1 increases, and R1 both end voltage increases, so that
Overcurrent self-locking protects triode combination Q2, Q3 conducting of circuit, and S, G pole tension of power MOS pipe Q1 reduces and switch-off power MOS
Pipe Q1 realizes output channel and automatically shuts down defencive function in output overcurrent.
In the pole the D output end of power MOS pipe Q1, can be realized by the high and low of output level by divider resistance R9, R11
To the opening of metal-oxide-semiconductor Q6, control is turned off, and then realizes bright, the control of going out of Light-emitting diode LED 1, i.e., externally provides the output
The indicator light of multi-channel output signal low and high level is bright, go out signal.
Processor sends outputs state detection instruction (Check_Command) to output state by Magnetic isolation chip U1 and examines
Slowdown monitoring circuit, it is open-minded that triode combines Q8, Q7.Outputs state detection circuit obtains output electricity in the pole the D output end of power MOS pipe Q1
Ordinary mail number is input to the input terminal of optocoupler through triode Q7 after power resistor R16 and zener diode D3 decompression, optocoupler every
From output feedback signal (Output_Feedback) to processor.Finally realize the outputs state detection and inspection of the output channel
Survey the isolation feedback of signal.
In addition, identical as the above outputs state detection circuit theory for the down Monitor Unit circuit for exporting power supply.
The apparatus embodiments described above are merely exemplary, wherein the circuit list as illustrated by the separation member
Member may or may not be physically separated, and the circuit unit of part description can be or can also be with as a whole
It is not physically separated.Those of ordinary skill in the art are without paying creative labor, it can understand simultaneously
Implement.
Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations；Although
Present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that: it still may be used
To modify the technical solutions described in the foregoing embodiments or equivalent replacement of some of the technical features；
And these are modified or replaceed, technical solution of various embodiments of the present invention that it does not separate the essence of the corresponding technical solution spirit and
Range.
Claims (10)
1. a kind of digital output card, including output power supply characterized by comprising
Overcurrent self-locking protects circuit and power MOS pipe switching circuit；
Power MOS pipe is equipped in the power MOS pipe switching circuit, the switch order for exporting according to processor passes through function
The conducting and disconnection of the source electrode and drain electrode of rate metal-oxide-semiconductor, the on-off of control output power supply, realize digital output；
The overcurrent self-locking protects circuit, for disconnecting power MOS pipe when the electric current of digital output is greater than preset threshold
The on state of source electrode and drain electrode.
2. digital output card according to claim 1, which is characterized in that overcurrent self-locking protection circuit includes the
One branch and second branch；
The first branch, for connecting the source electrode and the output power supply of the power MOS pipe；
The second branch, for when the electric current of digital output is less than preset threshold, make the grid of the power MOS pipe with
The output power supply disconnects, when the electric current of digital output is greater than preset threshold, make the grid of the power MOS pipe with
Export power supply conducting.
3. digital output card according to claim 2, which is characterized in that the first branch and the second branch
Parallel connection, the first branch include at least one resistance, and the second branch includes at least one triode.
4. digital output card according to claim 1, which is characterized in that further include output state observation circuit, institute
It states output state observation circuit to connect with output end, after the output state Monitoring instruction for receiving processor, obtains output end
Level signal, and the level signal of the output end is fed back into processor.
5. digital output card according to claim 1, which is characterized in that further include power supply down Monitor Unit electricity
Road, the power supply down Monitor Unit circuit, for being input to the overcurrent certainly in the level signal of the output power supply
Before lock protection circuit, the power supply state of the output power supply is obtained, and feeds back to processor.
6. digital output card according to claim 1, which is characterized in that in the power MOS pipe switching circuit
Output end is equipped with output terminal protecting circuit, over-voltage that the output terminal protecting circuit exports for realizing the digital signal and
Anti-reverse protection.
7. digital output card according to claim 1, which is characterized in that in the power MOS pipe switching circuit
Output end is additionally provided with output state LED indicating circuit, for showing the output state of output high level.
8. digital output card according to claim 1, which is characterized in that further include board temperature sensing circuit, use
In the temperature of monitoring board.
9. digital output card according to claim 1, which is characterized in that further include voltage regulator circuit, exported for making
The voltage signal of power supply output is stablized.
10. digital output card according to claim 1, which is characterized in that the power MOS pipe switching circuit, institute
It states output state observation circuit, the power supply down Monitor Unit circuit and board processor and does electrical isolation processing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910585724.XA CN110365322A (en) | 2019-07-01 | 2019-07-01 | A kind of digital output card |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910585724.XA CN110365322A (en) | 2019-07-01 | 2019-07-01 | A kind of digital output card |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110365322A true CN110365322A (en) | 2019-10-22 |
Family
ID=68217804
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910585724.XA Pending CN110365322A (en) | 2019-07-01 | 2019-07-01 | A kind of digital output card |
Country Status (1)
| Country | Link |
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| CN (1) | CN110365322A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115865062A (en) * | 2023-02-20 | 2023-03-28 | 浙江国利信安科技有限公司 | Digital quantity output module |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104332945A (en) * | 2014-10-30 | 2015-02-04 | 深圳市汇川技术股份有限公司 | High-speed digital output circuit with overcurrent protection and integrated circuit |
| CN107623511A (en) * | 2016-07-14 | 2018-01-23 | 上海沪工汽车电器有限公司 | A kind of vehicle solid-state relay for including NMOS tube with overcurrent protection |
-
2019
- 2019-07-01 CN CN201910585724.XA patent/CN110365322A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104332945A (en) * | 2014-10-30 | 2015-02-04 | 深圳市汇川技术股份有限公司 | High-speed digital output circuit with overcurrent protection and integrated circuit |
| CN107623511A (en) * | 2016-07-14 | 2018-01-23 | 上海沪工汽车电器有限公司 | A kind of vehicle solid-state relay for including NMOS tube with overcurrent protection |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115865062A (en) * | 2023-02-20 | 2023-03-28 | 浙江国利信安科技有限公司 | Digital quantity output module |
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