CN203166863U - Bidirectional electrical level conversion circuit and electronic product - Google Patents
Bidirectional electrical level conversion circuit and electronic product Download PDFInfo
- Publication number
- CN203166863U CN203166863U CN 201320178071 CN201320178071U CN203166863U CN 203166863 U CN203166863 U CN 203166863U CN 201320178071 CN201320178071 CN 201320178071 CN 201320178071 U CN201320178071 U CN 201320178071U CN 203166863 U CN203166863 U CN 203166863U
- Authority
- CN
- China
- Prior art keywords
- level
- conversion circuit
- power supply
- bidirectional
- type 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 - Lifetime
Links
Images
Landscapes
- Logic Circuits (AREA)
Abstract
The utility model discloses a bidirectional electrical level conversion circuit and an electronic product. The bidirectional electrical level conversion circuit is used for bidirectional conversion between a first electrical level and a second electrical level. The bidirectional electrical level conversion circuit comprises two electrical level interfaces, two power sources and two NPN-type triode; the base of a first NPN-type triode is connected with a first power source, and the emitter of the first NPN-type triode is connected with is connected with the first power source and a first electrical level interface respectively, and the collector of the first NPN-type triode is connected with a second power source and a second electrical level interface respectively; and the base of a second NPN-type triode is connected with the first power source, and the emitter of the second NPN-type triode is connected with the second power source and the second electrical level interface respectively, and the collector of the second NPN-type triode is connected with the first power source and the first electrical level interface respectively. The bidirectional electrical level conversion circuit is structured by discrete components; and the bidirectional electrical level conversion circuit is advantageous in simple structure, low cost, bidirectional high precision conversion between two kinds of electrical levels, and stable and reliable performance, can greatly meet the requirement for the accuracy of communication electrical level when data communication is performed between chips, and can ensure the security of chip interfaces.
Description
Technical field
The utility model belongs to data communication technology field, specifically, relates to a kind of for the circuit design that realizes two kinds of level signal bi-directional conversion.
Background technology
Along with the continuous development of electronic technology, the situation that needs to carry out data communication between two chips is more and more general.And for different chips, the communication level that its interface is supported has nothing in common with each other, and therefore need set up level shifting circuit between two chips, to satisfy the request signal transmission of chip chamber.
But along with the continuous lifting of digit chip technology, the communication between the chip requires more and more strictness to the accuracy of level, and this just has higher requirement to the conversion accuracy of level shifting circuit.And for present level shifting circuit, three kinds of structure forms of main existence: a kind of is to adopt the dedicated convert chip to cooperate simple peripheral circuit to make up the level shifting circuit that forms, though this level shifting circuit can be realized two kinds of bi-directional conversion between level, and can guarantee certain conversion accuracy, but owing to need to use special-purpose integrated chip, so the hardware cost height, have the specific scope of application and additional function.Second kind is the unidirectional level shifting circuit that adopts discrete component to build, though hardware cost is low, can only realize the unidirectional conversion of level, can not carry out the mutual conversion between two varying levels.The third is the coarse bidirectional level conversion circuit that adopts discrete component to build, though this level shifting circuit can be realized the mutual conversion between two kinds of level, but conversion accuracy is not high, need to consider the voltage endurance capability of chip interface and to the identification capability of level, and coarse communication level also can produce certain influence to the useful life of chip.
Based on this, as the high accuracy bi-directional conversion between how lower two kinds of level of cost realization, be the subject matter that present data communication field needs to be resolved hurrily.
Summary of the invention
The purpose of this utility model is to provide a kind of bidirectional level conversion circuit that adopts discrete component to set up and form, and on the basis of effective control hardware cost, has realized the high accuracy bi-directional conversion between two kinds of level.
In order to solve the problems of the technologies described above, the utility model is achieved by the following technical solutions:
A kind of bidirectional level conversion circuit is used for carrying out bi-directional conversion between first level and second level, comprises two electric level interfaces, two-way power supply and two NPN type triodes; Wherein, the base stage of a NPN type triode connects first power supply, and emitter connects first power supply and first electric level interface respectively, and collector electrode connects second source and second electric level interface respectively; The base stage of the 2nd NPN type triode connects first power supply, and emitter connects second source and second electric level interface respectively, and collector electrode connects first power supply and first electric level interface respectively.
Further, the described first power source voltage value is lower than the magnitude of voltage of second source.
Preferably, described first power supply is+DC power supply of 3.3V; Described second source is+DC power supply of 5V.
Further again, the described first power source voltage value equals the amplitude that first electric level interface requires the level signal transmitted; The magnitude of voltage of described second source equals the amplitude that second electric level interface requires the level signal transmitted.
Preferably, the level signal by described first electric level interface and the transmission of second electric level interface is the Transistor-Transistor Logic level signal.
Further again, the base stage of described two NPN type triodes connects described first power supply via a pull-up resistor separately; Described first power supply connects the emitter of a NPN type triode and the collector electrode of the 2nd NPN type triode respectively via first current-limiting resistance; Described second source connects the collector electrode of a NPN type triode and the emitter of the 2nd NPN type triode respectively via second current-limiting resistance.
In order further to improve the stability of level transmissions, described two electric level interfaces are separately via a filter capacitor ground connection.
Further, described two electric level interfaces are connected after one tunnel build-out resistor separately, again with described two corresponding connections of NPN type triode.
Based on above-mentioned bidirectional level conversion circuit, the utility model has also proposed a kind of electronic product that adopts described bidirectional level conversion circuit design, the internal circuit board of described electronic product is provided with for the level shifting circuit that carries out bi-directional conversion between first level and second level, is provided with two electric level interfaces, two-way power supply and two NPN type triodes in described bidirectional level conversion circuit; Wherein, the base stage of a NPN type triode connects first power supply, and emitter connects first power supply and first electric level interface respectively, and collector electrode connects second source and second electric level interface respectively; The base stage of the 2nd NPN type triode connects first power supply, and emitter connects second source and second electric level interface respectively, and collector electrode connects first power supply and first electric level interface respectively.By controlling the break-make sequential of two NPN type triodes, to realize the bi-directional conversion between first level signal and second level signal.
Further, described two electric level interfaces respectively with electronic product in the communication interface of two integrated chips connect one to one, to satisfy the data communication requirement between two chips.
Compared with prior art, advantage of the present utility model and good effect are: bidirectional level conversion circuit of the present utility model adopts the discrete component device to set up and forms, simple in structure, with low cost, realized the two-way high accuracy conversion between two kinds of level on the effective basis of control hardware cost, stable and reliable for performance, can satisfy between the chip when carrying out data communication the accuracy requirement to communication level well, guaranteed that the fail safe of chip interface and chip to the accurate identification of institute's received communication level, have prolonged the useful life of integrated chip.
Description of drawings
In order to be illustrated more clearly in the technical scheme among the utility model embodiment, will do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below.Apparently, the accompanying drawing in describing below only is embodiment more of the present utility model, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the theory diagram of the bidirectional level conversion circuit that proposes of the utility model;
Fig. 2 is the circuit theory diagrams of a kind of embodiment of the bidirectional level conversion circuit that proposes of the utility model.
Embodiment
Below in conjunction with the accompanying drawing among the utility model embodiment, the technical scheme among the utility model embodiment is clearly and completely described.Obviously, described embodiment only is a part of embodiment in the utility model, rather than whole embodiment.Based on the embodiment in the utility model, those of ordinary skills are not making all other embodiment that obtain under the creative work prerequisite, all belong to the scope of the utility model protection.
For the advantage that makes technical solutions of the utility model is clearer, below in conjunction with drawings and Examples the utility model is explained.
Embodiment one, present embodiment is in order to reach the purpose of two kinds of two-way high accuracy conversions of level signal, abandoning tradition adopts the circuit design scheme of dedicated convert chip, adopt the discrete component device to build bidirectional level conversion circuit, and then in the bi-directional conversion that realizes the varying level signal and satisfy under the prerequisite that the high accuracy conversion requires, realized the obvious reduction of hardware cost.
Referring to shown in Figure 1, the bidirectional level conversion circuit of present embodiment mainly by first electric level interface that is used for transmission first level, be used for second electric level interface of transmission second level and be connected between two electric level interfaces, the level shifting circuit establishment that is used for carrying out bi-directional conversion between first level and second level forms.Wherein, described level shifting circuit is mainly built by discrete components and parts such as triode and resistance, not only can reach the level conversion precision suitable with the dedicated convert chip, and compare and use the dedicated convert chip significantly to reduce hardware cost, be adapted at applying in the fierce relatively consumer electronics product of price competition.
Fig. 2 is the circuit theory diagrams of a kind of embodiment of level shifting circuit among Fig. 1, comprises two-way power supply VCC1, VCC2, two NPN type triode Q1, Q2 and several resistive elements.Wherein, described two-way power supply VCC1, VCC2 can be the different DC power supply of two-way magnitude of voltage, and the magnitude of voltage of the first power supply VCC1 should be lower than the magnitude of voltage of second source VCC2.For example: the first power supply VCC1 is+DC power supply of 3.3V; Second source VCC2 is+DC power supply of 5V etc.For two NPN type triode Q1, Q2, the base stage of the one NPN type triode Q1 is connected the first power supply VCC1 by the pull-up resistor R3 that connects, the emitter of triode Q1 connects the described first power supply VCC1 by the first current-limiting resistance R2, and is connected with the first electric level interface 3.3V_IO; The collector electrode of triode Q1 connects second source VCC2 by the second current-limiting resistance R6, and is connected with the second electric level interface 5V_IO.Similar with it, for the 2nd NPN type triode Q2, the base stage of the 2nd NPN type triode Q2 can be connected the first power supply VCC1 by pull-up resistor R4, the emitter of the 2nd NPN type triode Q2 is connected second source VCC2 by the second current-limiting resistance R6, and be connected with the second electric level interface 5V_IO; The collector electrode of the 2nd NPN type triode Q2 connects the described first power supply VCC1 by the first current-limiting resistance R2, and is connected with the first electric level interface 3.3V_IO.
In the present embodiment, in order to realize the high accuracy conversion of two-way level signal, the magnitude of voltage of the described first power supply VCC1 should equal the amplitude that the first electric level interface 3.3V_IO requires the level signal transmitted, i.e. the high level amplitude of the Transistor-Transistor Logic level signal by first electric level interface 3.3V_IO transmission; And the magnitude of voltage of second source VCC2 should equal the amplitude that the second electric level interface 5V_IO requires the level signal transmitted, i.e. the high level amplitude of the Transistor-Transistor Logic level signal by second electric level interface 5V_IO transmission.
Require the Transistor-Transistor Logic level signal of transmission 3.3V with the first electric level interface 3.3V_IO, it is that example describes that the second electric level interface 5V_IO requires the Transistor-Transistor Logic level signal of transmission 5V, at this moment, should select+DC power supply of 3.3V is as the first power supply VCC1, the DC power supply of selection+5V is as second source VCC2, thereby realize the high-low level signal by first electric level interface 3.3V_IO transmission 0-3.3V, by the high-low level signal of second electric level interface 5V_IO transmission 0-5V.
With the first power supply VCC1 be+DC power supply of 3.3V below, second source VCC2 is example for the DC power supply of+5V, and the operation principle of the bidirectional level conversion circuit that present embodiment is proposed is specifically described.
1, the transfer process from the 3.3V level signal to the 5V level signal:
When the Transistor-Transistor Logic level signal that inserts by the first electric level interface 3.3V_IO is high level (3.3V), the one NPN type triode Q1 is in cut-off state owing to its base voltage (3.3V) equals its emitter voltage (3.3V), and the 2nd NPN type triode Q2 enters cut-off state equally owing to its base voltage (3.3V) is lower than its emitter voltage (5V).At this moment, second source VCC2 acts on the second electric level interface 5V_IO by the second current-limiting resistance R6, therefore, and by the high level of second electric level interface 5V_IO output 5V.
When the Transistor-Transistor Logic level signal that inserts by the first electric level interface 3.3V_IO was low level (0V), a NPN type triode Q1 was because the difference of its base voltage (3.3V) and its emitter voltage (0V) greater than the conduction voltage drop of 0.7V, and enters the saturation conduction state.At this moment, the collector voltage of a NPN type triode Q1 is pulled down to 0V, thereby the magnitude of voltage of putting the second electric level interface 5V_IO is 0V, namely exports the low level of 0V by the second electric level interface 5V_IO.
Thus, just realized the conversion of 0-3.3V level signal to the 0-5V level signal.
2, the transfer process from the 5V level signal to the 3.3V level signal:
When the Transistor-Transistor Logic level signal that inserts by the second electric level interface 5V_IO is high level (5V), the 2nd NPN type triode Q2 is in cut-off state owing to its base voltage (3.3V) is lower than its emitter voltage (5V), and a NPN type triode Q1 enters cut-off state equally owing to its base voltage (3.3V) equals its emitter voltage (3.3V).At this moment, the first power supply VCC1 acts on the first electric level interface 3.3V_IO by the first current-limiting resistance R2, therefore, and by the high level of first electric level interface 3.3V_IO output 3.3V.
When the Transistor-Transistor Logic level signal that inserts by the second electric level interface 5V_IO was low level (0V), the 2nd NPN type triode Q2 was because the difference of its base voltage (3.3V) and its emitter voltage (0V) greater than the conduction voltage drop of 0.7V, and enters the saturation conduction state.At this moment, the collector voltage of the 2nd NPN type triode Q2 is pulled down to 0V, thereby the magnitude of voltage of putting the first electric level interface 3.3V_IO is 0V, namely exports the low level of 0V by the first electric level interface 3.3V_IO.
Thus, just realized the conversion of 0-5V level signal to the 0-3.3V level signal.
In order to improve the stability of level signal transmission, also have additional build-out resistor R1/R5 and filter capacitor C1/C2 at the described first electric level interface 3.3V_IO and the second electric level interface 5V_IO place, referring to shown in Figure 2.Wherein, the first electric level interface 3.3V_IO connects the emitter of a described NPN type triode Q1 and the collector electrode of the 2nd NPN type triode Q2 by with after build-out resistor R1 connects, and by filter capacitor C2 ground connection, with filtering interference signals.The second electric level interface 5V_IO connects the collector electrode of a described NPN type triode Q1 and the emitter of the 2nd NPN type triode Q2 by with after build-out resistor R5 connects, and by filter capacitor C1 ground connection, with filtering interfering, the stability of inhibit signal transmission.
Bidirectional level conversion circuit shown in Figure 2 is applied in the electronic product, two different integrated chips of interface level of supporting at communication interface in the electronic product, described bidirectional level conversion circuit can be connected between described two integrated chips, require the first low integrated chip for interface level, its communication interface should be connected the described first electric level interface 3.3V_IO; For demanding second integrated chip of interface level, its communication interface should be connected the second electric level interface 5V_IO.Then, select the DC power supply consistent with the interface level amplitude of first integrated chip as the first power supply VCC1, select the DC power supply consistent with the interface level amplitude of second integrated chip as second source VCC2, just can realize two-way level converting and the transmission of signal of communication thus, satisfy the data communication requirement between integrated chip.
Certainly; above-mentioned explanation is not to be to restriction of the present utility model; the utility model also is not limited in above-mentioned giving an example, and the variation that those skilled in the art make in essential scope of the present utility model, remodeling, interpolation or replacement also should belong to protection range of the present utility model.
Claims (10)
1. a bidirectional level conversion circuit is used for carrying out bi-directional conversion between first level and second level, it is characterized in that: comprise two electric level interfaces, two-way power supply and two NPN type triodes; Wherein, the base stage of a NPN type triode connects first power supply, and emitter connects first power supply and first electric level interface respectively, and collector electrode connects second source and second electric level interface respectively; The base stage of the 2nd NPN type triode connects first power supply, and emitter connects second source and second electric level interface respectively, and collector electrode connects first power supply and first electric level interface respectively.
2. bidirectional level conversion circuit according to claim 1, it is characterized in that: the described first power source voltage value is lower than the magnitude of voltage of second source.
3. bidirectional level conversion circuit according to claim 2 is characterized in that: the described first power source voltage value equals the amplitude that first electric level interface requires the level signal transmitted; The magnitude of voltage of described second source equals the amplitude that second electric level interface requires the level signal transmitted.
4. bidirectional level conversion circuit according to claim 3 is characterized in that: the level signal by described first electric level interface and the transmission of second electric level interface is the Transistor-Transistor Logic level signal.
5. bidirectional level conversion circuit according to claim 2 is characterized in that: described first power supply is the DC power supply of+3.3V; Described second source is+DC power supply of 5V.
6. according to each described bidirectional level conversion circuit in the claim 1 to 5, it is characterized in that: the base stage of described two NPN type triodes connects described first power supply via a pull-up resistor separately; Described first power supply connects the emitter of a NPN type triode and the collector electrode of the 2nd NPN type triode respectively via first current-limiting resistance; Described second source connects the collector electrode of a NPN type triode and the emitter of the 2nd NPN type triode respectively via second current-limiting resistance.
7. according to each described bidirectional level conversion circuit in the claim 1 to 5, it is characterized in that: described two electric level interfaces are separately via a filter capacitor ground connection.
8. bidirectional level conversion circuit according to claim 7 is characterized in that: described two electric level interfaces are connected after one tunnel build-out resistor separately, again with described two corresponding connections of NPN type triode.
9. electronic product, it is characterized in that: the internal circuit board of described electronic product is provided with as the described bidirectional level conversion circuit of each claim in the claim 1 to 9.
10. electronic product according to claim 9 is characterized in that: described two electric level interfaces respectively with electronic product in the communication interface of two integrated chips connect one to one.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320178071 CN203166863U (en) | 2013-04-11 | 2013-04-11 | Bidirectional electrical level conversion circuit and electronic product |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320178071 CN203166863U (en) | 2013-04-11 | 2013-04-11 | Bidirectional electrical level conversion circuit and electronic product |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203166863U true CN203166863U (en) | 2013-08-28 |
Family
ID=49028016
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201320178071 Expired - Lifetime CN203166863U (en) | 2013-04-11 | 2013-04-11 | Bidirectional electrical level conversion circuit and electronic product |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203166863U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103199847A (en) * | 2013-04-11 | 2013-07-10 | 青岛海信宽带多媒体技术有限公司 | Bi-directional level switching circuit and electronic product |
-
2013
- 2013-04-11 CN CN 201320178071 patent/CN203166863U/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103199847A (en) * | 2013-04-11 | 2013-07-10 | 青岛海信宽带多媒体技术有限公司 | Bi-directional level switching circuit and electronic product |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103199847A (en) | Bi-directional level switching circuit and electronic product | |
| CN201113972Y (en) | Level switching circuit | |
| CN201788434U (en) | Multipath bidirectional digital controlled constant current source | |
| CN203658888U (en) | USB power supply compensating circuit and portable electronic equipment | |
| CN203166863U (en) | Bidirectional electrical level conversion circuit and electronic product | |
| CN202721661U (en) | UART level switching circuit | |
| CN203661030U (en) | Electrical level switching circuit and circuit board having same | |
| CN207408937U (en) | A kind of conversion circuit of TTL RS 232s interface level | |
| CN203573130U (en) | Digital knob switch multiplexing device and electronic equipment using same | |
| CN204272077U (en) | A kind of PWM turns 4-20mA signal isolation change-over circuit | |
| CN102681449B (en) | A kind of switching value input circuit of engineering machinery nonshared control unit | |
| CN204215202U (en) | A kind of low cost, high precision 4 ~ 20mA current signal output circuit | |
| CN204886919U (en) | Plain type logic level converting circuit structure | |
| CN203151466U (en) | Positive-negative logic level conversion switching circuit | |
| CN203250233U (en) | Direct current voltage reduction circuit and electronic products | |
| CN202914850U (en) | Modified proportional valve drive return circuit | |
| CN104375444A (en) | 4-20 mA current signal output circuit | |
| CN103441544B (en) | The multivoltage output control circuit of intelligent charger | |
| CN202043034U (en) | Level shift circuit realizing shifting from 5v signal to 3.3v signal for singlechip system | |
| CN204290706U (en) | The power supply that a kind of RS232 signal drives | |
| CN204680001U (en) | A kind of STM32 chip program programming circuit | |
| CN206759420U (en) | Bidirectional level conversion circuit | |
| CN203661017U (en) | Comparator realization circuit | |
| CN204462920U (en) | Based on the voltage signal conditioning circuit of controllable accurate source of stable pressure | |
| CN203883804U (en) | RS232 and digital processor level converting circuit with capacitor floating control |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20130828 |