CN103795397A - Level shifter and operational amplifier - Google Patents

Abstract

The invention relates to a potential converter, comprising: a signal receiving module, which is turned on or off according to an input signal; a potential adjustment module, which generates an adjusted output signal according to the input signal, and the potential adjustment module includes a first a connection terminal and a second connection terminal, wherein the second connection terminal is coupled to the signal receiving module; and a switch module has a first terminal coupled to the first connection terminal and a second terminal coupled to the second connection terminal end, when the switch module is turned on, a current path is formed between the first connection end, the second connection end and the signal receiving module through the switch module, when the switch module is not turned on, a current path Unable to flow from the first connection to the second connection.

Description

Potential shifters and operational amplifiers

technical field

The present invention relates to a level shifter and an operational amplifier, in particular to a level shifter and an operational amplifier with a switching element in it that can be turned off and a current is rapidly increased.

Background technique

In the known circuit, a level shifter is used to adjust the potential of the signal so that subsequent components can have normal performance. For example, digital components using digital signals need the signal to be above 1.2V to correctly judge the logic value of the signal. However, the potential of the signal itself may only be 250mv, so a potential converter is needed to adjust the potential value of the signal so that the digital component can work normally. operate.

FIG. 1 illustrates a potential converter 100 in the prior art. The potential converter 100 includes a potential adjustment module 101 and a signal receiving module 103 . The signal receiving module 103 is used for receiving a differential input signal, and the differential input signal is formed by the first input signal V _in+ and the second input signal V _in− . The potential adjustment module 101 generates an adjusted output signal V _o according to the differential input signal. The potential adjustment module 101 has a first transistor Tr ₁ and a second transistor Tr ₂ , the control terminal T _CTr1 of the first transistor Tr ₁ , the control terminal T _CTr2 of the second transistor Tr ₂ and the second terminal T _2Tr2 are commonly coupled to A connection point T. The signal receiving module 103 includes a first switch SW ₁ and a second switch SW ₂ , the control terminal T _CSW1 of the first switch SW ₁ and the control terminal T _CSW2 of the second switch SW ₂ respectively receive the first and second input signals V _in+ and V _in- , and whether the first switch SW ₁ and the second switch SW ₂ are turned on or not is controlled by the first and second input signals V _in+ and V _in- respectively.

However, under such a circuit structure, the second transistor Tr ₂ will always be in a conducting state, and a current will always flow. FIG. 2 is a schematic diagram of the current status of a potential converter in the prior art, wherein the horizontal axis represents time, and the vertical axis represents the current value of the current I flowing through the first transistor _Tr1 or the second transistor _Tr2 . As shown in FIG. 2 , the current curve C _I marked with a dotted line represents the current value of the current I under ideal conditions, and the current curve C _R marked with a solid line represents the current value of the current I under actual conditions. Under ideal conditions, the current I will quickly rise to a predetermined current value I _W and quickly drop to zero. However, in an actual situation, the second transistor Tr ₂ cannot be quickly connected to the ground potential, so the connection point T cannot be quickly dropped to the ground potential, and the rising and falling speed of the current will be slow and delayed. In addition, when the first transistor _Tr1 is not turned on, there will still be a small current _Ir continuously flowing through the second transistor _Tr2 . Because the current rises and falls slowly and there is a constant current flowing through the second transistor Tr ₂ continuously, the sum of the currents flowing through the first transistor Tr ₁ or the second transistor Tr ₂ per unit time is relatively large (indicated by the oblique line in Figure 2 area). As known to those skilled in the art, the power consumption of an element is related to the sum of the currents flowing through the element. Therefore, under the circuit structure of FIG. 1 , the potential adjustment module 101 will consume relatively large power. Moreover, under such a circuit structure, the delay phenomenon of the current rising and falling will also reduce the overall performance of the circuit.

Contents of the invention

Therefore, it is an object of the present invention to provide a potential converter capable of turning off the switching elements therein and rapidly increasing the current.

Another object of the present invention is to provide an operational amplifier capable of turning off the switching element and rapidly increasing the current.

An embodiment of the present invention discloses a potential converter for generating an adjusted output signal, comprising: a signal receiving module having at least one signal input terminal for receiving at least one input signal, and conducting according to the input signal or non-conductive; a potential adjustment module generates the adjusted output signal according to the input signal, the potential adjustment module includes a first connection terminal and a second connection terminal, wherein the second connection terminal is coupled to the signal receiving module and a switch module having a first terminal coupled to the first connection terminal and a second terminal coupled to the second connection terminal, when the switch module is turned on, a current path is formed in the switch module through the switch module Between the first connection end, the second connection end and the signal receiving module, when the switch module is not conducted, a current cannot flow from the first connection end to the second connection end.

The structures of the above-mentioned embodiments are not limited to be used in level converters, but can also be used in operational amplifiers.

According to the aforementioned embodiments, the transistor coupled to the switch module in the potential adjustment module can be turned off, and the current provided by the potential adjustment module can rise rapidly, which can improve the problems in the known technology.

Description of drawings

FIG. 1 shows a potential converter of known technology.

FIG. 2 is a schematic diagram of a current state of a potential converter in the prior art.

FIG. 3 shows a schematic diagram of a potential converter according to the present invention.

FIG. 4 is a schematic diagram illustrating an example of the detailed structure of the level converter according to the present invention.

FIG. 5 is a schematic diagram of the current state of the level converter according to the present invention.

Description of main component symbols

100, 300 potential converter

101, 301 potential adjustment module

103, 303 signal receiving module

305 switch module

T connection point

Tr ₁ first transistor

Tr ₂ second transistor

SW ₁ first switching element

SW ₂ second switching element

SW ₃ third switching element

T _1Tr1 , T _1Tr2 , T _1SW1 , T _1SW2 , T _1SW3 , T _sm1 first end

T _2Tr1 , T _2Tr2 , T _2SW1 , T _2SW2 , T _2SW3 , T _sm2 second terminal

T _CTr1 , T _CTr2 , T _CSW1 , T _CSW2 , T _CSW3 , T _smC control terminal

T _S1 , T _S2 signal input terminal

T _adj1 first connection terminal

T _adj2 second connection terminal

Detailed ways

FIG. 3 shows a schematic diagram of a potential converter 300 according to the present invention. Please note that although the content in FIG. 3 uses the circuit structure shown in FIG. 1 as an example to explain the content of the present invention, it is not limited thereto. The concepts disclosed in the present invention can be applied to other circuit structures. For example, the signal receiving module 303 in FIG. 3 receives a differential signal, but it can also be a single input signal. In addition, although the circuit in FIG. 3 and FIG. 4 is called a level converter, it can also be used for other purposes, for example, it can be used as an operational amplifier.

As shown in FIG. 3 , the potential converter 300 includes a potential adjustment module 301 , a signal receiving module 303 and a switch module 305 . The signal receiving module 303 has two signal input terminals T _S1 and T _S2 to respectively receive the first and second input signals V _in+ and V _in- , and the signal receiving module 303 receives the first and second input signals V _in+ and V _in- The logic level of the conduction or non-conduction. The potential adjustment module 301 generates an adjusted output signal V _o according to the first and second input signals V _in+ and V _in- , and includes a first connection terminal T _adj1 and a second connection terminal T _adj2 , wherein the first connection terminal T _adj1 is coupled to the switch module 305 , and the second connection terminal T _adj2 is coupled to the signal receiving module 303 . The switch module 305 has a first terminal T _sm1 coupled to the first connection terminal T _adj1 and a second terminal T _sm2 coupled to the second connection terminal T _adj2 . When the switch module 305 is turned on, a current path is formed between the first connection terminal T _adj1 and the second connection terminal T _adj2 through the switch module 305 . That is, when the switch module 305 is turned on, a current can flow from the first connection terminal T _adj1 through the switch module 305 , and then flow through the second connection terminal T _adj2 to the signal receiving module 303 .

In one embodiment, the signal receiving module 303 includes: a first signal input terminal T _S1 for receiving the first input signal V _in+ , and a second signal input terminal T _S2 for receiving the second input signal V _in− . In addition, the signal receiving module 303 further includes a first switch element SW ₁ and a second switch element SW ₂ . The first switch element SW ₁ has a control terminal T _CSW1 as the first signal input terminal TS ₁ , has a first terminal T _1SW1 coupled to the potential adjustment module 301 , and has a second terminal T _2SW1 coupled to a first signal input terminal TS 1 . A potential (ground potential in this example). The second switch element SW ₂ has a control terminal T _CSW2 as the second signal input terminal T _S2 , and has a first terminal T _1SW2 coupled to the second connection terminal T _adj2 and the second terminal T _sm2 of the switch module 305 , and It has a second terminal T _2SW2 coupled to the first potential. When the second switch element SW ₂ is turned on, the switch module 305 is turned off, otherwise when the second switch element SW ₂ is turned off, the switch module 305 is turned on. In this embodiment, the control terminal T _smc of the switch module 305 also receives the second input signal V _in- and is turned on or off according to the second input signal V _in- . However, the switch module 305 can also be controlled by a signal different from the second input signal V _in− .

The potential adjustment module 301 includes a first transistor Tr ₁ and a second transistor Tr ₂ . The first transistor Tr ₁ includes a control terminal T _CTr1 coupled to the second connection terminal T _adj2 , a first terminal T 1Tr1 coupled to a second potential V _cc , and a first terminal T _1Tr1 coupled to the first switching element SW ₁ A second terminal T _2Tr1 of the terminal T _1SW1 . The second transistor Tr ₂ includes a control terminal T _CTr2 coupled to the second connection terminal T _adj2 , a first terminal T _1Tr2 coupled to the second potential V _cc , and a second terminal T adj1 coupled to the first connection terminal T _adj1 Terminal T _2Tr2 .

Please refer to FIG. 4 , which shows a schematic diagram of an example of the detailed structure of the level converter according to the present invention. In FIG. 4, a third transistor SW ₃ is used as the switch module 305 in FIG. 3, but please note that the switch module 305 may include other components other than the third transistor SW ₃ , and may also be realized by other components. As long as the same function can be achieved. The first end T _1SW3 of the third switch element SW ₃ is the first end T _sm1 of the switch module 305 in FIG. 3 , and the second end T 2SW3 of the third switch element SW ₃ is the second end T _2SW3 of the switch module 305 in FIG. 3 T _sm2 , whose control terminal T _CSW3 is the control terminal T _smc of the switch module 305 in FIG. 3 , is coupled to the control terminal T _CSW2 of the second switch element SW ₂ to receive the second input signal V _in− .

In the embodiment of FIG. 4 , the first switch element SW ₁ and the second switch element SW ₂ are N-type metal oxide semiconductor transistors, and the first transistor Tr ₁ , the second transistor Tr ₂ and the third switch element SW ₃ are P type metal oxide semiconductor transistor. Therefore, when the second switch element SW ₂ is turned on (the second input signal V _in- is at a high potential), the third switch element SW ₃ is turned off. In this case, the potential of the connection point T can quickly drop to the ground potential so that the current flowing through the first transistor Tr ₁ rises rapidly, and the second transistor Tr ₂ is not turned on. Conversely, when the second switch element SW ₂ is off (the second input signal V _in- is at a low potential), the third switch element SW ₃ is turned on. At this time, a current path will be formed between the first connection terminal T _adj1 and the second connection terminal T _adj2 . At this time, according to the state of the first input signal Vin+, it will be determined whether there is current output from the first transistor _Tr1 .

FIG. 5 is a schematic diagram of the current state of the level converter according to the present invention. As shown in FIG. 5 , the current I flowing through the first transistor Tr ₁ can rise rapidly to provide a large current more efficiently, so that the overall performance of the circuit is better. In addition, the second transistor Tr ₂ can be turned off and not turned on, so there is no problem in the prior art that the second transistor Tr ₂ is always on and current flows all the time. The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

Claims (10)

1. A potential converter for generating an adjusted output signal, comprising: A signal receiving module, having at least one signal input terminal for receiving at least one input signal, and conducting or not conducting according to the input signal; A potential adjustment module, which generates the adjusted output signal according to the input signal, the potential adjustment module includes a first connection terminal and a second connection terminal, wherein the second connection terminal is coupled to the signal receiving module; and A switch module, having a first terminal coupled to the first connection terminal and a second terminal coupled to the second connection terminal, when the switch module is turned on, a current path is formed on the first connection terminal through the switch module Between the connecting end, the second connecting end and the signal receiving module, when the switch module is not conducting, current is blocked from flowing from the first connecting end to the second connecting end. 2. potential converter as claimed in claim 1, is characterized in that, this signal receiving module comprises: a first signal input terminal for receiving a first input signal; a second signal input terminal for receiving a second input signal; A first switch element has a control terminal as the first signal input terminal, has a first terminal coupled to the potential adjustment module, and has a second terminal coupled to a first potential; and A second switch element has a control terminal as the second signal input terminal, and has a first terminal coupled to the second connection terminal and the second terminal of the switch module, and has a second terminal coupled to to the first potential; Wherein, when the second switch element is turned on, the switch module is not turned on, and when the second switch element is not turned on, the switch module is turned on. 3. The potential converter according to claim 2, wherein the potential adjustment module comprises: A first transistor, including a control terminal coupled to the second connection terminal, a first terminal coupled to a second potential, and a second terminal coupled to the first terminal of the first switching element; and A second transistor includes a control terminal coupled to the second connection terminal, a first terminal coupled to the second potential, and a second terminal coupled to the first connection terminal. 4. potential converter as claimed in claim 3, is characterized in that, this switch module comprises: A third switch element, including a first end as the first end of the switch module, a second end as the second end of the switch module, and a control coupled to the control end of the second switch element end. 5. The potential converter according to claim 4, wherein the first switch element, the second switch element and the third switch element are N-type metal oxide semiconductor transistors, and the first transistor and the second switch element The second transistor is a P-type metal oxide semiconductor transistor. 6. An operational amplifier for generating an adjusted output signal, comprising: A signal receiving module, having at least one signal input terminal for receiving at least one input signal, and conducting or not conducting according to the input signal; A potential adjustment module, which generates the adjusted output signal according to the input signal, the potential adjustment module includes a first connection terminal and a second connection terminal, wherein the second connection terminal is coupled to the signal receiving module; and A switch module, having a first terminal coupled to the first connection terminal and a second terminal coupled to the second connection terminal, when the switch module is turned on, a current path is formed on the first connection terminal through the switch module Between the connection end, the second connection end and the signal receiving module, when the switch module is not conducting, current is blocked from flowing from the first connection end to the second connection end. 7. The operational amplifier according to claim 6, wherein the signal receiving module comprises: a first signal input terminal for receiving a first input signal; a second signal input terminal for receiving a second input signal; A first switch element has a control terminal as the first signal input terminal, has a first terminal coupled to the potential adjustment module, and has a second terminal coupled to a first potential; and A second switch element has a control terminal as the second signal input terminal, and has a first terminal coupled to the second connection terminal and the second terminal of the switch module, and has a second terminal coupled to to the first potential; Wherein, when the second switch element is turned on, the switch module is not turned on, and when the second switch element is not turned on, the switch module is turned on. 8. The operational amplifier according to claim 7, wherein the potential adjustment module comprises: a first transistor, including a control terminal coupled to the second connection terminal, a first terminal coupled to a second potential, and a second terminal coupled to the first terminal of the first switching element; and A second transistor includes a control terminal coupled to the second connection terminal, a first terminal coupled to the second potential, and a second terminal coupled to the first connection terminal. 9. The operational amplifier of claim 8, wherein the switch module comprises: A third switch element, including a first end as the first end of the switch module, a second end as the second end of the switch module, and a control coupled to the control end of the second switch element end. 10. The operational amplifier according to claim 9, wherein the first switch element, the second switch element and the third switch element are N-type metal oxide semiconductor transistors, and the first transistor and the second switch element The transistor is a P-type metal oxide semiconductor transistor.

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