Input buffer circuit and input buffer method
阅读说明：本技术 一种输入缓冲电路和输入缓冲方法 (Input buffer circuit and input buffer method ) 是由 喻彪 于 2019-10-11 设计创作，主要内容包括：本申请公开了一种输入缓冲电路和输入缓冲方法,包括：输入端口、输出端口、第一反相器、第二反相器、低电压电源输入端口、第一开关管和节点电位调整单元；不论输入端口输入的是高电平还是低电平,通过第一开关管、第一反相器、第二反相器和节点电位调整单元的共同作用,都整个输入缓冲电路最终输出低电平,或者输出的电平在低电平和低电压电源输入端口输入的低电源电平之间,还可以实现高压到低压电平移位的输入,进而使得低压器件能够实现高压输入低压输出,并且本申请的技术方案无静态功耗,电路结构简单,易于实现和集成。(The application discloses input buffer circuit and input buffer method, including: the low-voltage power supply comprises an input port, an output port, a first phase inverter, a second phase inverter, a low-voltage power supply input port, a first switching tube and a node potential adjusting unit; no matter the input of input port is high level or low level, through the combined action of first switch tube, first inverter, second inverter and node potential adjustment unit, all whole input buffer circuit finally outputs low level, or the level of output is between the low power level of low level and low voltage power input port input, can also realize the input of high pressure to low pressure level shift, and then make the low-voltage device can realize high pressure input low pressure output, and the technical scheme of this application does not have static power consumption, circuit structure is simple, easily realize and integrate.)
1. An input buffer circuit, comprising: the low-voltage power supply comprises an input port (1), an output port (2), a first phase inverter (3), a second phase inverter (4), a low-voltage power supply input port (5), a first switch tube (6) and a node potential adjusting unit (7); wherein, a first end of the first switch tube (6) is connected with the input port (1) to receive an input signal, a second end of the first switch tube (6) is connected with the low-voltage power input port (5) to receive a low-power-supply-voltage signal, and a third end of the first switch tube (6) is connected with an input end of the first inverter (3); a first terminal of the first inverter (3) is connected with the low-voltage power input port (5) to receive a low-power voltage signal, an output terminal of the first inverter (3) is connected with an input terminal of the second inverter (4), and a second terminal of the first inverter (3) is connected with a low level; a first end of the second inverter (4) is connected with the low-voltage power input port (5) to receive a low-voltage power signal, an output end of the second inverter (4) is connected with the output port (2) to output an output signal of the input buffer circuit, and a second end of the second inverter (4) is connected with a low level; the first end of the node potential adjusting unit (7) is connected with the input end of the first phase inverter (3), the second end of the node potential adjusting unit (7) is connected with the output end of the first phase inverter (3), the third end of the node potential adjusting unit (7) is connected with the low-voltage power supply input port (5) to receive a low-power-supply voltage signal, and the fourth end of the node potential adjusting unit (7) is connected with a low level.
2. The buffer circuit according to claim 1, wherein the node potential adjusting unit (7) includes a weak pull-down (71) and a weak pull-up (72); wherein the drain of the weak pull-down (71) and the drain of the weak pull-up (72) are connected to the input of the first inverter (3), the gate of the weak pull-down (71) and the gate of the weak pull-up (72) are connected to the output of the first inverter (3), the back gate of the weak pull-down (71) is connected to the source after which the source of the weak pull-down (71) is connected to a low level, the source of the weak pull-up (72) is connected to the back gate after which the source of the weak pull-up (72) is connected to the low voltage power input port (5) to receive a low supply voltage signal.
3. The snubber circuit according to claim 1, wherein the first inverter (3) comprises a PMOS transistor and an NMOS transistor; the source electrode of the PMOS tube is connected to a low-voltage power supply input port (5) to receive a low-voltage power supply signal, the gate electrode of the PMOS tube is connected to the input end of the first inverter (3) after the source electrode is connected to the back gate, and the drain electrode of the PMOS tube is connected to the output end of the first inverter (3); the drain electrode of the NMOS tube is connected to the output end of the first inverter (3), the grid electrode of the NMOS tube is connected to the input end of the first inverter (3), and after the back gate is connected to the source electrode, the source electrode is connected with low level.
4. The snubber circuit according to claim 1, wherein the second inverter (4) comprises a PMOS transistor and an NMOS transistor; the source of the PMOS tube is connected to a low-voltage power supply input port (5) to receive a low-voltage power supply signal, the gate of the PMOS tube is connected to the output end of the first inverter (3) after the source of the PMOS tube is connected to the back gate, and the drain of the PMOS tube is connected to the output port (2); the drain electrode of the NMOS tube is connected to the output port (2), the grid electrode of the NMOS tube is connected to the output end of the first inverter (3), the back gate is connected to the source electrode, and then the source electrode is connected with low level.
5. The buffer circuit according to claim 1, wherein the first switch transistor (7) is an NMOS transistor, wherein a drain of the NMOS transistor is connected to the input port (1) to receive the input signal, a gate of the NMOS transistor is connected to the low-voltage power input port (5) to receive the low-voltage power signal, and a back gate of the NMOS transistor is connected to a source of the NMOS transistor, and a source of the NMOS transistor is connected to the input terminal of the first inverter (3).
6. The snubber circuit according to claim 2, wherein the weak pull-down element (8) is an NMOS transistor.
7. A snubber circuit according to claim 2, characterized in that the weak pull-up (9) is a PMOS transistor.
8. The snubber circuit according to claim 1, wherein the first switching transistor (7) is a high voltage mosfet device with gate and source withstanding high voltages or a lateral double diffused LDMOS device.
9. An input buffering method for an input buffering circuit according to any one of claims 1 to 8, comprising:
the input port inputs low level to the first switch tube;
the first switch tube pulls down the potential of the input end of the first phase inverter;
the output end potential of the first inverter rises to the low power supply level of the low-voltage power supply input port;
the node potential adjusting unit pulls down the potential of the input end of the first inverter to a low level;
the second inverter outputs a low level from the output port.
10. An input buffering method for an input buffering circuit according to any one of claims 1 to 8, comprising:
the input port inputs high level to the first switch tube;
the first switching tube pulls up the input end potential of the first phase inverter;
the potential of the output end of the first inverter is reduced to a low level;
the node potential adjusting unit pulls up the input end potential of the first inverter to the low power level of the low-voltage power input port;
the second inverter outputs a low power supply level from the output port.
Technical Field
The present disclosure relates to electronic circuits and semiconductor technologies, and particularly to an input buffer circuit and an input buffer method.
Background
In part of advanced CMOS integrated circuit processes, only input and output MOSFET devices with low voltage resistance are provided, the voltage difference among a grid G, a source S, a drain D and a back gate B of the devices cannot exceed low power supply voltage, and the devices can only communicate with external circuits with the same input and output levels.
However, some communication interface protocols stipulate that the circuit interface should operate at a high voltage, or some external circuits requiring communication only provide input/output interfaces with a high voltage, so that these chips designed and produced by using low-voltage input/output devices cannot operate at a high voltage at present.
Therefore, how to make the low voltage input/output device capable of receiving high voltage input becomes a problem to be solved by those skilled in the art.
Disclosure of Invention
The application provides an input buffer circuit and an input buffer method, which enable a low-voltage input/output device to accept high-voltage input.
The application provides an input buffer circuit, including: the low-voltage power supply comprises an input port, an output port, a first phase inverter, a second phase inverter, a low-voltage power supply input port, a first switching tube and a node potential adjusting unit; a first end of the first switch tube is connected with the input port to receive an input signal, a second end of the first switch tube is connected with the low-voltage power supply input port to receive a low-power-supply-voltage signal, and a third end of the first switch tube is connected with an input end of the first inverter; a first end of the first inverter is connected with the low-voltage power supply input port to receive a low-power supply voltage signal, an output end of the first inverter is connected with an input end of the second inverter, and a second end of the first inverter is connected with a low level; a first end of the second inverter is connected with the low-voltage power supply input port to receive a low-voltage power supply signal, an output end of the second inverter is connected with the output port to output an output signal of the input buffer circuit, and a second end of the second inverter is connected with a low level; the first end of the node potential adjusting unit is connected with the input end of the first phase inverter, the second end of the node potential adjusting unit is connected with the output end of the first phase inverter, the third end of the node potential adjusting unit is connected with the low-voltage power supply input port to receive a low-power-supply voltage signal, and the fourth end of the node potential adjusting unit is connected with a low level.
With reference to the first aspect, in one implementable manner of the first aspect, the node potential adjustment unit includes a weak pull-down piece and a weak pull-up piece; the drain electrode of the weak pull-down piece and the drain electrode of the weak pull-up piece are connected to the input end of the first inverter, the gate electrode of the weak pull-down piece and the gate electrode of the weak pull-up piece are connected to the output end of the first inverter, after the back gate of the weak pull-down piece is connected to the source electrode, the source electrode of the weak pull-down piece is connected to the low level, after the source electrode of the weak pull-up piece is connected to the back gate, the source electrode of the weak pull-up piece is connected to the low-voltage power supply input port to receive a low power supply voltage signal.
With reference to the first aspect, in one implementation manner of the first aspect, the first inverter includes one PMOS transistor and one NMOS transistor; the source of the PMOS tube is connected to the low-voltage power supply input port to receive a low-voltage power supply signal, the gate of the PMOS tube is connected to the input end of the first inverter after the source of the PMOS tube is connected to the back gate, and the drain of the PMOS tube is connected to the output end of the first inverter; the drain electrode of the NMOS tube is connected to the output end of the first inverter, the grid electrode of the NMOS tube is connected to the input end of the first inverter, the back gate of the NMOS tube is connected to the source electrode, and then the source electrode of the NMOS tube is connected with low level.
With reference to the first aspect, in one implementation manner of the first aspect, the second inverter includes a PMOS transistor and an NMOS transistor; the source of the PMOS tube is connected to the low-voltage power supply input port to receive a low-voltage power supply signal, the gate of the PMOS tube is connected to the output end of the first inverter after the source of the PMOS tube is connected to the back gate, and the drain of the PMOS tube is connected to the output port; the drain electrode of the NMOS tube is connected to the output port, the grid electrode of the NMOS tube is connected to the output end of the first inverter, the back gate of the NMOS tube is connected to the source electrode, and then the source electrode of the NMOS tube is connected with low level.
With reference to the first aspect, in an implementation manner of the first aspect, the first switch tube is an NMOS tube, wherein a drain of the NMOS tube is connected to the input port to receive the input signal, a gate of the NMOS tube is connected to the low-voltage power supply input port to receive the low-supply-voltage signal, and after the back gate is connected to the source, the source is connected to the input end of the first inverter.
With reference to the first aspect, in one implementation manner of the first aspect, the weak pull-down element is an NMOS transistor.
With reference to the first aspect, in one implementation manner of the first aspect, the weak pull-up element is a PMOS transistor.
With reference to the first aspect, in one implementation manner of the first aspect, the first switch tube is a high-voltage mosfet device with a high-voltage-resistant gate and a high-voltage-resistant source or a lateral double-diffused LDMOS device.
In a second aspect, the present application provides an input buffering method for the buffered input circuit of the first aspect, the method comprising:
the input port inputs low level to the first switch tube;
the first switch tube pulls down the potential of the input end of the first phase inverter;
the output end potential of the first inverter rises to the low power supply level of the low-voltage power supply input port;
the node potential adjusting unit pulls down the potential of the input end of the first inverter to a low level;
the second inverter outputs a low level from the output port.
In a third aspect, the present application further provides an input buffering method for the buffered input circuit of the first aspect, including:
the input port inputs high level to the first switch tube;
the first switching tube pulls up the input end potential of the first phase inverter;
the potential of the output end of the first inverter is reduced to a low level;
the node potential adjusting unit pulls up the input end potential of the first inverter to the low power level of the low-voltage power input port;
the second inverter outputs a low power supply level from the output port.
As can be seen from the above technical solutions, the present application provides an input buffer circuit and an input buffer method, including: the low-voltage power supply comprises an input port, an output port, a first phase inverter, a second phase inverter, a low-voltage power supply input port, a first switching tube and a node potential adjusting unit; no matter the input of input port is high level or low level, through the combined action of first switch tube, first inverter, second inverter and node potential adjustment unit, all whole input buffer circuit finally outputs low level, or the level of output is between the low power level of low level and low voltage power input port input, can also realize the input of high pressure to low pressure level shift, and then make the low-voltage device can realize high pressure input low pressure output, and the technical scheme of this application does not have static power consumption, circuit structure is simple, easily realize and integrate.
Drawings
In order to more clearly illustrate the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without any creative effort.
Fig. 1 is a block diagram of an input buffer circuit according to an embodiment of the present disclosure;
fig. 2 is a circuit diagram of an input buffer circuit according to an embodiment of the present application.
Illustration of the drawings:
wherein, 1-input port; 2-an output port; 3-a first inverter; 4-a second inverter; 5-a low voltage power input port; 6-a first switch tube; 7-node potential adjusting means; 71-weak pull-down; 72-weak pull-up.
Detailed Description
In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.
Fig. 1 is a structural diagram of an input buffer circuit according to an embodiment of the present application. As shown in fig. 1, the present application provides an input buffer circuit including: the low-voltage power supply comprises an
Fig. 2 is a circuit diagram of an input buffer circuit according to an embodiment of the present application, and as shown in fig. 2, the node potential adjustment unit 7 includes a weak pull-down element 71 and a weak pull-up element 72; wherein the drain of the weak pull-down 71 and the drain of the weak pull-up 72 are connected to the input terminal of the
As shown in fig. 2, the
As shown in fig. 2, the
As shown in fig. 2, the first switch tube 7 is an NMOS tube, wherein a drain of the NMOS tube is connected to the
In addition, the first switch tube 7 may also be a high voltage mosfet device with a high voltage-resistant gate and a high voltage-resistant source or a lateral double-diffused LDMOS device.
The input buffer circuit that this application embodiment provided, no matter the input of input port be high level or low level, through the combined action of first switch tube, first phase inverter, second phase inverter and node potential adjustment unit, the final output low level of all whole input buffer circuit, or the level of output is between the low power level of low level and low voltage power input port input, can also realize the input of high pressure to low pressure level shift, and then make the low voltage device can realize high pressure input low voltage output.
The embodiment of the present application further provides an input buffering method, which is used for the input buffering circuit in the above embodiment, and the method includes:
the input port inputs low level to the first switch tube;
the first switch tube pulls down the potential of the input end of the first phase inverter;
the output end potential of the first inverter rises to the low power supply level of the low-voltage power supply input port;
the node potential adjusting unit pulls down the potential of the input end of the first inverter to a low level;
the second inverter outputs a low level from the output port.
In addition, another input buffering method is also provided in the embodiments of the present application, and is also used for the input buffering circuit in the embodiments, where the method includes:
the input port inputs high level to the first switch tube;
the first switching tube pulls up the input end potential of the first phase inverter;
the potential of the output end of the first inverter is reduced to a low level;
the node potential adjusting unit pulls up the input end potential of the first inverter to the low power level of the low-voltage power input port;
the second inverter outputs a low power supply level from the output port.
The two INPUT buffering methods provided by the embodiment of the present application can be specifically described by using the INPUT buffering circuit shown in fig. 2, and the INPUT buffering circuit provided by the embodiment of the present application can implement that a low-voltage INPUT/OUTPUT device accepts high-voltage INPUT, where an
when the INPUT is low level (GND level), because the back gate of the first switch tube 6 is forward conducted to the parasitic PN junction diode of the drain, the potential of the node1 is pulled down, at this time, the NMOS tube in the
When the INPUT of the INPUT is increased from the low level (GND level) to the high level VH, because the gate of the first switch tube 6 is connected to VM, the first switch tube 6 is firstly turned on to pull up the potential of the node1, the PMOS tube in the
When the INPUT voltage is decreased from a high level VH to a low level (GND level), when the INPUT voltage is lower than a forward conduction voltage of one diode of VM, a parasitic PN junction diode from a back gate to a drain of the first switch tube 6 is conducted to pull down the voltage of the node1, then an NMOS tube in the
According to the above operation principle, the input buffer circuit provided in the embodiment of the present application implements VH to VM input logic shift using a low voltage device: the INPUT INPUTs VH level, and the OUTPUT OUTPUTs VM level; INPUT is between the GND level and OUTPUT is between GND level. The output voltage shifts between VM to GND for subsequent circuit processing.
In addition, the first switch tube 6, which is a low-voltage device in the present application, is used to isolate a high-voltage input signal, when a low level is input, the weak pull-down device 71 is used to pull down the voltage of the node1 to stabilize the potential of the node1, and when a high level is input, the weak pull-up device 72 is used to pull up the voltage of the node1 to pull up the source and back gate potentials of the first switch tube 6 to VM, so that the voltage difference between the four terminals of the first switch tube 6 does not exceed the normal operating voltage range of the low-voltage device.
As can be seen from the above technical solutions, the present application provides an input buffer circuit and an input buffer method, including: the low-voltage power supply comprises an input port, an output port, a first phase inverter, a second phase inverter, a low-voltage power supply input port, a first switching tube and a node potential adjusting unit; no matter the input of input port is high level or low level, through the combined action of first switch tube, first inverter, second inverter and node potential adjustment unit, all whole input buffer circuit finally outputs low level, or the level of output is between the low power level of low level and low voltage power input port input, can also realize the input of high pressure to low pressure level shift, and then make the low-voltage device can realize high pressure input low pressure output, and the technical scheme of this application does not have static power consumption, circuit structure is simple, easily realize and integrate.
Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.
It will be understood that the present application is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the application is limited only by the appended claims.
- 上一篇：一种医用注射器针头装配设备
- 下一篇：一种三态门