CN102520654B - Protective circuit capable of enhancing robustness of control interface circuit - Google Patents
Protective circuit capable of enhancing robustness of control interface circuit Download PDFInfo
- Publication number
- CN102520654B CN102520654B CN201110387857.XA CN201110387857A CN102520654B CN 102520654 B CN102520654 B CN 102520654B CN 201110387857 A CN201110387857 A CN 201110387857A CN 102520654 B CN102520654 B CN 102520654B
- Authority
- CN
- China
- Prior art keywords
- control
- circuit
- diode
- transistor
- resistor
- 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
Landscapes
- Logic Circuits (AREA)
- Electronic Switches (AREA)
Abstract
The invention provides a protective circuit capable of enhancing robustness of a control interface circuit, so as to enhance the robustness of the control interface circuit and reduce the probability of circuit fault caused by external operations of products. The protective circuit is arranged between a control source and a drive circuit, and comprises a diode and a resistor; a control signal output end of the control source is connected to a control signal input end of the drive circuit through the diode arranged in forward direction; the resistor is used as a logic pull-down resistor, and a negative terminal of the diode is connected to the digital ground through the resistor. The protective circuit has simple structure, skillfully uses the combination of the diode and the resistor, effectively prevents a connection control source chip from being damaged by transient reverse current, enhances the system robustness, ensures the control effectiveness of outputting low level by a TTL (Transistor-Transistor Logic) level control source chip, and successfully solves the technical difficulties which are hard to overcome for a long time in the on-board control circuit field.
Description
Technical field
The present invention relates to control circuit designing technique, be specifically related to a kind of holding circuit that strengthens control interface robustness.
Background technology
Discrete magnitude output interface circuit is necessary functional circuit in embedded Aviation AirborneComputer, and Main Function comprises 2 aspects: 1. the present duty of instruct computer self; 2. control the duty of target device.The driver output of discrete magnitude output interface can adopt photoelectricity isolation, electromagnetic relay, power tube to realize conventionally, but because this class component volume is larger, when required driver output interface too much and circuit board space have in limited time and should not adopt.The user demand (as SG2823, chip structure is shown in Fig. 1) of many-sided design factors such as the higher Darlington transistor of integrated level can meeting spatial, quantity, driving force.Darlington transistor integrated chip SG2823 encapsulates 8 roads and drives interface, the compatible Transistor-Transistor Logic level of control inputs level, and output driving current is supported 600mA.
The discrete magnitude driving circuit being directly comprised of Transistor-Transistor Logic level control source and Darlington transistor as shown in Figure 2, this circuit is no problem with regard to function, but necessary strict implement attended operation altogether in using, it is the housing that circuit " digitally " connects place casing, Darlington transistor " " connecting the 28V power supply ground that output drive end is corresponding, 28V power supply ground must be realized and being connected altogether by bonding ground wire with cabinet housing ground terminal.If do not connected by above-mentioned requirements, can cause Transistor-Transistor Logic level to control output port property abnormality or the damage in source.Note the internal circuit (seeing Fig. 1, Fig. 2) that chip 2823 handbooks provide: between ' ' end and TTL control input end, have a diode, clearly when " the 28V ground " of chip 2823 level, higher than Transistor-Transistor Logic level, controlling the level of exporting in source is just to have the output terminal that current direction Transistor-Transistor Logic level is controlled source, thereby the output port that causes Transistor-Transistor Logic level to control source lost efficacy.Connect altogether guaranteed 28V and digitally between in equipotential state, two " " separate and cannot guarantee that electromotive force unanimously can increase the probability that circuit damages.Product is complicated in machine assembly environment, in disassembly process, does not connect and on improper or machine, connects altogether All other routes and occur that anomalous effects arrives normally altogether unavoidably because carelessness connects bonding ground wire or bonding ground wire, all may cause discrete magnitude output interface fault.After product is paid installation use in batches, this type of fault frequency of occurrences is high, has increased the maintenance cost of product.Therefore must do further optimization effectively to reduce the probability of discrete magnitude output interface fault to this circuit.
Summary of the invention
The invention provides a kind of holding circuit that strengthens control interface robustness, to strengthen control interface robustness, reduce because product peripheral operation is former thereby cause the probability of fault.
Technical scheme of the present invention is as follows:
Strengthen a holding circuit for control interface robustness, be arranged between control source and driving circuit, its special character is: comprise a diode and a resistance; The described diode that the control signal output terminal in control source arranges by forward is connected to the control signal input end of driving circuit; Described resistance is as logic pull down resistor, and the negative terminal of diode also connects " digitally " by this resistance.
Holding circuit of the present invention is particularly useful for control source and adopts Transistor-Transistor Logic level to control source chip, and described driving circuit adopts the circuit structure of Darlington transistor chip.
The present invention has the following advantages:
The present invention is simple in structure, utilize dexterously the combination of diode and resistance, effectively having prevented from connect controlling source chip swings to electric current because of transient state and damages, and strengthened the robustness of system, guarantee the control validity of Transistor-Transistor Logic level control source chip output low level, reduced largely because the improper Transistor-Transistor Logic level that causes of the connection of bonding ground wire is controlled the probability that source port breaks down, successfully solved airborne control circuit field and be difficult to for a long time the technical barrier effectively overcoming.
Accompanying drawing explanation
Fig. 1 is Darlington transistor SG2823 chip internal structure schematic diagram;
Fig. 2 is the discrete magnitude output interface circuit schematic diagram of traditional scheme;
Fig. 3 is the central principle figure of holding circuit of the present invention;
Fig. 4 is for increasing the discrete magnitude output interface circuit system construction drawing after holding circuit of the present invention.
Embodiment
For Transistor-Transistor Logic level, control source chip and Darlington transistor chip, a kind of holding circuit that strengthens control interface robustness of the present invention's design, be arranged at Transistor-Transistor Logic level and control between source chip and Darlington transistor chip, this holding circuit mainly comprises a diode and a resistance; The described diode that the control signal output terminal of Transistor-Transistor Logic level control source chip arranges by forward is connected to the control signal input end of Darlington transistor chip; Described resistance is as logic pull down resistor, and the negative terminal of diode connects " digitally " by this resistance.
Transistor-Transistor Logic level is controlled source chip and is arranged in cabinet, its circuit " digitally " connects the housing of place casing, Darlington transistor " " connecting the 28V power supply ground that output drive end is corresponding, 28V power supply ground is realized and being connected altogether by bonding ground wire with cabinet housing ground terminal.
As shown in Figure 3, Figure 4, circuit utilizes the unilateal conduction characteristic of diode can stop electric current to flow into A point by B point, and the chip that effectively prevents from connecting A end is swung to electric current because of transient state and damaged.Resistance R 1 has two kinds of effects, effect 1: the transient state of order from B is swung to electric current introducing digitally and with the consumption of heat energy form; Effect 2: as logic pull down resistor, when A point input logic ' zero ' (low level) state, can guarantee that B point connects the also logic in standard ' zero ' current potential of the input port controlled, prevent that B point is in logic " tri-state " state (being vacant state), realize the deterministic control that B is ordered.This circuit structure simply has engineering realizability.
Diode V1 is for stoping the abnormal current on " 28V ground " to flow to the output port that Transistor-Transistor Logic level is controlled source, and the effect of pull down resistor R3 is the control validity (avoiding chip SG2823 input control port in vacant state) of guaranteeing Transistor-Transistor Logic level control source chip output low level.This circuit has possessed very strong robustness, and greatly degree reduces because the improper Transistor-Transistor Logic level that causes of the connection of bonding ground wire is controlled the probability that source port breaks down.
Holding circuit of the present invention is not limited to and is applied in the design of airborne discrete magnitude output interface circuit, and other need to carry out oppositely suppressing to avoid " tri-state " and strengthen in the circuit design of robustness all can applying.
Claims (2)
1. strengthen a holding circuit for control interface robustness, be arranged between control source and driving circuit, it is characterized in that: comprise a diode and a resistance; The described diode that the control signal output terminal in control source arranges by forward is connected to the control signal input end of driving circuit; Described resistance is as logic pull down resistor, and the negative terminal of diode also connects " digitally " by this resistance.
2. holding circuit according to claim 1, is characterized in that: described control source adopts Transistor-Transistor Logic level to control source chip, and described driving circuit adopts Darlington transistor chip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110387857.XA CN102520654B (en) | 2011-11-29 | 2011-11-29 | Protective circuit capable of enhancing robustness of control interface circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110387857.XA CN102520654B (en) | 2011-11-29 | 2011-11-29 | Protective circuit capable of enhancing robustness of control interface circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102520654A CN102520654A (en) | 2012-06-27 |
| CN102520654B true CN102520654B (en) | 2014-09-24 |
Family
ID=46291607
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110387857.XA Active CN102520654B (en) | 2011-11-29 | 2011-11-29 | Protective circuit capable of enhancing robustness of control interface circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102520654B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107066414B (en) * | 2017-04-25 | 2023-12-29 | 南京国电南自维美德自动化有限公司 | Enhanced parallel communication circuit and method |
| CN114442715B (en) * | 2021-12-29 | 2023-08-18 | 中国航空工业集团公司西安航空计算技术研究所 | 28V or open circuit discrete quantity output circuit |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202339492U (en) * | 2011-11-29 | 2012-07-18 | 中国航空工业集团公司第六三一研究所 | Protection circuit for enhancing robustness of control interface circuit |
-
2011
- 2011-11-29 CN CN201110387857.XA patent/CN102520654B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202339492U (en) * | 2011-11-29 | 2012-07-18 | 中国航空工业集团公司第六三一研究所 | Protection circuit for enhancing robustness of control interface circuit |
Non-Patent Citations (1)
| Title |
|---|
| 王尧等.1.3半导体二极管的简单应用.《模拟电子技术》.东南大学出版社,1994,第17-18页. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102520654A (en) | 2012-06-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104298575B (en) | Mainboard debug circuit | |
| CN102520654B (en) | Protective circuit capable of enhancing robustness of control interface circuit | |
| CN106024042A (en) | Method for enhancing reliability of hard disk backplane | |
| CN103647540A (en) | Solid-state wide-voltage isolation type direct-current relay | |
| CN104767505A (en) | Switching circuit with circuit protection function | |
| CN105656176A (en) | High-reliability power switching circuit and electronic device | |
| CN202339492U (en) | Protection circuit for enhancing robustness of control interface circuit | |
| CN203926092U (en) | Fan control circuitry | |
| CN105142984A (en) | Motor vehicle having two vehicle electrical systems with different vehicle-electrical-system voltages | |
| CN103325523B (en) | Electromagnet protection circuit | |
| CN202678968U (en) | Communication protecting circuit and air conditioner adopting the communication protecting circuit | |
| CN102270839B (en) | Electronic device with protective circuit | |
| CN102996885B (en) | Protection drive circuit of small-power electromagnetic coil | |
| CN103051325A (en) | Pull-up resistance circuit for preventing reverse current filling | |
| CN207319225U (en) | A kind of iic bus circuit with isolation features | |
| CN203387493U (en) | Digital signal isolating circuit for programmable logic controller (PLC) of scrapper plate conveyer | |
| CN101364804A (en) | Power-down protection apparatus of analogue switch | |
| CN203951189U (en) | A kind of negative control positive supply protective circuit | |
| CN202852128U (en) | Protection and drive circuit of low-power electromagnetic coil | |
| CN203151460U (en) | Turn-off switch of integrated circuit power supply | |
| CN105991115B (en) | Transmitter circuit, semiconductor device, and data transmission method | |
| CN204392225U (en) | A kind of drive circuit realizing interlocking | |
| CN203070003U (en) | Power supply controller | |
| CN204886163U (en) | LED lamps and lanterns power lightning protection circuit | |
| CN206802447U (en) | The linear solenoid valve control equipment of clutch |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |