Level shift circuit, control method thereof and electronic equipment

Abstract

The invention discloses a level shift circuit, a control method thereof and electronic equipment, and relates to the technical field of integrated circuits. The circuit comprises a logic control module, an AC / DC coupling module and an inverted output module, in the logic control module, a first signal input end is connected with an input signal source, and a second signal input end is connected with an enable signal source; the AC-DC coupling module comprises a DC coupling unit and an AC coupling unit; in the direct current coupling unit, a first control input end is connected with a first control output end, and a second control input end is connected with a second control output end; in the AC coupling unit, an AC coupling input end is connected with a first control output end; the AC coupling output end is connected with the DC coupling output end; the inverted input end of the inverted output module is connected with the DC coupling output end, and the inverted output end is used for outputting a target level shift signal. And a low-delay, high-speed and good-duty-ratio level shifting function can be realized for an alternating current signal and a direct current signal.

Description

Technical Field

[0001] The present application relates to the technical field of integrated circuits, and in particular to a level shifting circuit, a control method thereof, and an electronic device. Background Art

[0002] Level shifting circuits are widely used in integrated circuits. They are a crucial bridge in electronic systems and can solve the problem that different circuit modules or devices cannot communicate directly due to different operating voltages.

[0003] In the related art, a common level conversion circuit includes: two NMOS tubes (M1 and M2), two PMOS tubes (M3, M4) and two inverters (inv1, inv2). The disadvantage of this level conversion circuit is that if the size of the two NMOS tubes (M1 and M2) is not large enough, the turned-on NMOS tube cannot pull down the signal vop_1 or von_1 due to insufficient drive, resulting in failure of the level conversion function. If the size of the two NMOS tubes (M1 and M2) is made very large, the parasitic capacitance will limit the flipping speed of the signal vop_1 or von_1, so the circuit structure can generally only achieve a speed level of several hundred MHz. The currently common high-speed level conversion circuits are basically based on the following Figure 1 Improvements to the circuit architecture of the level shifter circuit shown in the figure, such as connecting PMOS or NMOS transistors in series, using low-voltage NMOS transistors, and adding bias voltages, have improved the level shift speed somewhat, but it is still not fast enough, and problems such as long delay and duty cycle imbalance remain unresolved. Therefore, how to implement a level shifter circuit that combines low latency, high speed, and a good duty cycle remains an urgent technical challenge. Summary of the Invention

[0004] This application aims to solve at least one of the technical problems existing in the prior art. To this end, this application proposes a level shifting circuit, a control method thereof, and an electronic device that, by combining an AC coupling unit with a DC coupling unit, can achieve low-latency, high-speed, and good-duty-cycle level shifting for both AC and DC signals.

[0005] In a first aspect, an embodiment of the present application provides a level shifting circuit, comprising: A logic control module includes a first signal input terminal, a second signal input terminal, a first control output terminal, a second control output terminal, and a first power input terminal; the first signal input terminal is connected to an input signal source, the second signal input terminal is connected to an enable signal source, and the first power input terminal is connected to a first power supply; An AC / DC coupling module includes: a DC coupling unit and an AC coupling unit; wherein the DC coupling unit includes a first control input terminal, a second control input terminal, a DC coupling output terminal, and a second power supply input terminal; the first control input terminal is connected to the first control output terminal, the second control input terminal is connected to the second control output terminal, and the second power supply input terminal is connected to the second power supply; the AC coupling unit includes an AC coupling input terminal and an AC coupling output terminal; the AC coupling input terminal is connected to the first control output terminal; and the AC coupling output terminal is connected to the DC coupling output terminal; The inverting output module includes an inverting input terminal, an inverting output terminal and a third power input terminal; the inverting input terminal is connected to the DC coupling output terminal, the inverting output terminal is used to output the target level transfer signal, and the third power input terminal is connected to the second power supply.

[0006] In a second aspect, an embodiment of the present application provides a control method for a level shifting circuit, which is applied to the level shifting circuit as described in the embodiment of the first aspect, wherein the level shifting circuit includes: a logic control module, an AC / DC coupling module, and an inverting output module; the AC / DC coupling module includes: a DC coupling unit and an AC coupling unit; The method comprises: When the enable signal is at a high level, the logic control module performs logic judgment processing based on the enable signal and the input signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, determines the on / off state of the branch where the AC coupling unit is located, controls the DC coupling unit to perform path selection and voltage division processing, and outputs a coupling signal to the inverting output module; wherein the input signal is a DC signal or an AC signal; The inverting output module performs inverting processing on the coupled signal and outputs a target level-shifted signal.

[0007] In a third aspect, an embodiment of the present application provides an electronic device, comprising the level shifting circuit as described in the embodiment of the first aspect.

[0008] The embodiments of the present application include: A level shifting circuit includes: a logic control module, an AC / DC coupling module, and an inverting output module; wherein the AC / DC coupling module includes: a DC coupling unit and an AC coupling unit; the level shifting circuit implements a level shifting function for both input AC and DC signals through AC coupling and DC coupling. During operation of the level shifting circuit, when the enable signal is high, the logic control module performs a logical judgment based on the enable signal and the input signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, determines the on / off state of the branch where the AC coupling unit is located, controls the DC coupling unit to perform a path selection and voltage division process, and outputs a coupled signal to the inverting output module; wherein the input signal is a DC signal or an AC signal; then, the inverting output module inverts the coupled signal and outputs a target level shifted signal; thus, a level shifting function with low latency, high speed, and good duty cycle can be implemented for both input DC and AC signals. That is, the embodiment of the present application can achieve low-latency, high-speed, and good duty cycle level shifting functions for both AC and DC signals by combining the AC coupling unit and the DC coupling unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a schematic diagram of the structure of a common level shift circuit in the prior art; Figure 2 This is a schematic diagram of the structure of a common AC-coupled level shift circuit in the prior art; Figure 3 This is a schematic diagram of the structure of a level shifting circuit provided by one embodiment of the present application; Figure 4 This is a schematic diagram of the specific structure of a level shifting circuit provided by an embodiment of the present application; Figure 5 This is a flowchart of the steps of a control method for a level shifting circuit provided by an embodiment of the present application. DETAILED DESCRIPTION

[0010] In order to make the purpose, technical solutions and advantages of this application more clear, this application is further described in detail below with reference to the accompanying drawings and embodiments.

[0011] It should be noted that although a logical order is shown in the flowchart in the description of this application, in some cases, the steps shown or described may be performed in an order different from that in the flowchart. In the description of this application, "several" means one or more, and "more" means two or more. The description of "first" and "second" is only used to distinguish technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0012] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein are for the purpose of describing the embodiments of this application only and are not intended to limit this application.

[0013] First, some terms used in this application are explained: VCC: Derived from the BJT circuit, it represents the collector supply voltage (such as +5V, +12V).

[0014] VDD: Derived from the MOSFET circuit, it represents the drain supply voltage (e.g. +3.3V, +1.8V).

[0015] The present application provides a level shifting circuit 100, a control method for the level shifting circuit 100, and an electronic device, relating to the field of integrated circuit technology. The circuit includes: a logic control module 110, an AC / DC coupling module 120, and an inverting output module 130. In the logic control module 110, a first signal input terminal 111 is connected to an input signal source Vin, and a second signal input terminal 112 is connected to an enable signal source. The AC / DC coupling module 120 includes a DC coupling unit 121 and an AC coupling unit 122. In the DC coupling unit 121, a first control input terminal 121A is connected to a first control output terminal 113, and a second control input terminal 121B is connected to a second control output terminal 114. In the AC coupling unit 122, an AC coupling input terminal 122A is connected to the first control output terminal 113, and an AC coupling output terminal 122B is connected to a DC coupling output terminal 121C. In the inverting output module 130, an inverting input terminal 131 is connected to a DC coupling output terminal 121C, and an inverting output terminal 132 is used to output a target level shifted signal Vout. It can realize low-latency, high-speed and good duty cycle level shifting function for both AC and DC signals.

[0016] The embodiments of the present application are further described below with reference to the accompanying drawings.

[0017] First, as Figure 3 As shown, an embodiment of the present application provides a level shifting circuit 100, comprising: a logic control module 110, an AC / DC coupling module 120, and an inverting output module 130. The logic control module 110, the AC / DC coupling module 120, and the inverting output module 130 are sequentially connected. The specific connection relationship between the logic control module 110, the AC / DC coupling module 120, and the inverting output module 130 is described below.

[0018] Specifically, the logic control module 110 includes a first signal input terminal 111, a second signal input terminal 112, a first control output terminal 113, a second control output terminal 114 and a first power input terminal; the first signal input terminal 111 is connected to the input signal Vin source, the second signal input terminal 112 is connected to the enable signal source, and the first power input terminal is connected to the first power supply VDD.

[0019] Specifically, the AC / DC coupling module 120 includes a DC coupling unit 121 and an AC coupling unit 122. The DC coupling unit 121 includes a first control input terminal 121A, a second control input terminal 121B, a DC coupling output terminal 121C, and a second power input terminal. The first control input terminal 121A is connected to the first control output terminal 113, the second control input terminal 121B is connected to the second control output terminal 114, and the second power input terminal is connected to the second power supply VCC. The AC coupling unit 122 includes an AC coupling input terminal 122A and an AC coupling output terminal 122B. The AC coupling input terminal 122A is connected to the first control output terminal 113, and the AC coupling output terminal 122B is connected to the DC coupling output terminal 121C. Specifically, the inverting output module 130 includes an inverting input terminal 131, an inverting output terminal 132 and a third power input terminal; the inverting input terminal 131 is connected to the DC coupling output terminal 121C, the inverting output terminal 132 is used to output the target level transfer signal Vout, and the third power input terminal is connected to the second power supply VCC.

[0020] Furthermore, the functions implemented by each circuit module in the level shifting circuit 100 are further described.

[0021] Specifically, the enable signal source is used to output the enable signal en, and the enable signal en can be a high level or a low level.

[0022] Specifically, the input signal Vin source is used to generate the input signal Vin, which can be an AC signal or a DC signal. It is understood that when the level shifter circuit 100 is applied to different integrated circuit systems, the circuit modules serving as the input signal Vin source may vary. Therefore, this application does not impose any specific limitations on the circuit modules serving as the input signal Vin source.

[0023] Specifically, the first power supply VDD is used to output the VDD power supply voltage to provide the power required for the logic control module 110 to work; the second power supply VCC is used to output the VCC power supply voltage to provide the power required for the AC / DC coupling module 120 and the inverting output module 130 to work.

[0024] Specifically, in the logic control module 110, the first signal input terminal 111 is used to receive the input signal Vin, and the second signal input terminal 112 is used to receive the enable signal en. The logic control module 110 is used to: perform logic judgment processing based on the enable signal en and the input signal Vin, output the first logic control signal vinp and the second logic control signal vinn to the AC / DC coupling module 120, so as to control the on / off state of the branch where the AC coupling unit 122 in the AC / DC coupling module 120 is located, control the DC coupling unit 121 to perform path selection and voltage division processing, and output the coupling signal to the inverting output module 130.

[0025] Specifically, in the AC / DC coupling module 120, the first control input terminal 121A is used to receive the first logic control signal vinp output by the logic control module 110, and the second control input terminal 121B is used to receive the second logic control signal vinn output by the logic control module 110; then, the on / off state of the branch where the AC coupling unit 122 is located is determined according to the first logic control signal vinp, and the DC coupling unit 121 is controlled to perform path selection and voltage division processing according to the first logic control signal vinp and the second logic control signal vinn, and output the coupling signal to the inverting output module 130.

[0026] Specifically, in the inverting output module 130, the inverting input terminal 131 is used to receive the coupling signal output by the AC / DC coupling module 120, and the inverting output module 130 is used to invert the coupling signal to obtain the target level transfer signal Vout; the inverting output terminal 132 is used to output the target level transfer signal Vout.

[0027] Furthermore, the specific structures of the logic control module 110 , the AC / DC coupling module 120 and the inverting output module 130 are described as follows.

[0028] According to some embodiments of the present application, Figure 4 As shown, the logic control module 110 includes: a NAND logic gate nand2, a first inverter inv1, and an AND logic gate and2. Figure 3 and Figure 4 , the specific connection relationship between the NAND logic gate nand2, the first inverter inv1, and the logic gate and2 is further explained.

[0029] Specifically, the first input terminal of the NAND logic gate nand2 is connected to the input signal Vin source, and the second input terminal of the NAND logic gate nand2 is connected to the enable signal source; wherein, the input signal Vin source is used to generate the input signal Vin; the enable signal source is used to generate the enable signal en; the input terminal of the first inverter inv1 is connected to the output terminal of the NAND logic gate nand2; the output terminal of the first inverter inv1 is the first control output terminal 113, and the first control output terminal 113 is connected to the AC coupling input terminal 122A; the first input terminal of the AND logic gate and2 is connected to the output terminal of the NAND logic gate nand2; the second input terminal of the AND logic gate and2 is connected to the enable signal source; the output terminal of the AND logic gate and2 is the second control output terminal 114, and the second control output terminal 114 is connected to the second control input terminal 121B of the DC coupling unit 121.

[0030] Furthermore, the functions of the NAND logic gate nand2, the first inverter inv1, and the AND logic gate and2 are further explained.

[0031] Specifically, the NAND logic gate nand2 is one of the most basic universal logic gates in digital circuits. Its core function is "AND first, then NOT". The logical expression of the NAND logic gate nand2 is: ; The logical operation performed by the NAND logic gate nand2 is: after performing the AND operation on input A and input B, the result of the AND logic operation is negated to obtain the output Y. Specifically, in the embodiments of the present application, Example 1: When the enable signal en is at a high level, the input signal Vin is a DC signal, and the DC signal is at a high level (i.e., 1), the NAND logic gate nand2 outputs a low level (i.e., 0). Example 2: When the enable signal en is at a high level, the input signal Vin is a DC signal, and the DC signal is at a low level (i.e., 0), the NAND logic gate nand2 outputs a high level (i.e., 1). Example 3: When the enable signal en is at a low level, the NAND logic gate nand2 outputs a high level (i.e., 1) regardless of whether the DC signal is at a high level or a low level.

[0032] Specifically, the logical expression of the first inverter inv1 is: The logical operation performed by the first inverter inv1 is: inverting the input A to obtain the output Y. Specifically, in the embodiments of the present application, Example 1: When the NAND logic gate nand2 outputs a high level to the first inverter inv1, the first inverter inv1 inverts the high point and outputs the first logic control signal vinp as a low level. Example 2: When the NAND logic gate nand2 outputs a low level to the first inverter inv1, the first inverter inv1 inverts the low point and outputs the first logic control signal vinp as a high level.

[0033] Specifically, the logical expression of the AND logic gate and2 is: ; The logical operation performed by the AND logic gate and2 is: perform a logical AND operation on input A and input B to obtain output Y. Specifically, in the embodiments of the present application, Example 1: When the enable signal en is a high level (i.e., 1), and the NAND logic gate nand2 outputs a high level (i.e., 1), the second logic control signal vinn output by the AND logic gate and2 is a high level (i.e., 1). Example 2: When the enable signal en is a high level (i.e., 1), and the NAND logic gate nand2 outputs a low level (i.e., 0), the second logic control signal vinn output by the AND logic gate and2 is a high level (i.e., 0). Example 3: When the enable signal en is a low level (i.e., 0), regardless of whether the DC signal is a high level or a low level, the second logic control signal vinn output by the AND logic gate and2 is a low level.

[0034] In the logic control module 110 provided in the embodiment of the present application, through the mutual cooperation between the NAND logic gate nand2, the first inverter inv1, and the logic gate and2, logical judgment processing can be performed according to the enable signal en and the input signal Vin, and the first logic control signal vinp and the second logic control signal vinn can be output to achieve reliable control of the AC / DC coupling module 120.

[0035] According to some embodiments of the present application, the AC coupling unit 122 includes: a coupling capacitor C, one end of the coupling capacitor C is an AC coupling input end 122A, and the other end of the coupling capacitor C is an AC coupling output end 122B; the AC coupling input end 122A is connected to the first control output end 113 of the first inverter inv1; and the AC coupling output end 122B is connected to the DC coupling output end 121C of the DC coupling unit 121.

[0036] It can be understood that coupling capacitor C has the function of isolating DC and passing AC, that is, blocking DC signals and allowing AC signals to pass. Based on the AC coupling function of coupling capacitor C, two examples are given to illustrate the specific process of determining the on / off state of the branch where AC coupling unit 122 is located based on the first logic control signal vinp. Example 1: When the enable signal en is at a high level and the input signal Vin is a DC signal, the first logic control signal vinp does not jump, but remains at a high level or a low level. This disconnects the branch where AC coupling unit 122 (i.e., coupling capacitor C) is located. Example 2: When the enable signal en is at a high level and the input signal Vin is an AC signal, the first logic control signal vinp jumps from a low level to a high level. This connects the branch where AC coupling unit 122 (i.e., coupling capacitor C) is located.

[0037] According to some embodiments of the present application, the DC coupling unit 121 includes: a voltage divider unit, a first switch tube Q1, and a second switch tube Q2; further, the specific connection relationship between the voltage divider unit, the first switch tube Q1, and the second switch tube Q2 is further described.

[0038] Specifically, the voltage divider unit includes: a first resistor R1, a second resistor R2 and a third resistor R3; one end of the third resistor R3 is connected to the second power supply VCC as the second power supply VCC end, and the other end of the third resistor R3 is connected to the inverting input end 131 as the DC coupling output end 121C.

[0039] Specifically, the gate of the first switch tube Q1 is connected to the output end of the AND logic gate and2 (i.e., the second control output end 114), the source of the first switch tube Q1 is grounded, and the drain of the first switch tube Q1 is connected between the AC coupling output end 122B and the DC coupling output end 121C of the coupling capacitor C through the first resistor R1.

[0040] Specifically, the gate of the second switch tube Q2 is connected to the output end of the first inverter inv1 (that is, the first control output end 113), the source of the second switch tube Q2 is grounded, and the drain of the second switch tube Q2 is connected between the AC coupling output end 122B and the DC coupling output end 121C of the coupling capacitor C through the second resistor R2.

[0041] According to some embodiments of the present application, the first switch transistor Q1 and the second switch transistor Q2 are both N-channel metal oxide semiconductor field effect transistors.

[0042] Furthermore, the functions implemented by the voltage dividing unit, the first switch tube Q1 and the second switch tube Q2 are further described.

[0043] Specifically, the first switch tube Q1 is used to receive the second logic control signal vinn output by the AND logic gate and2. When the second logic control signal vinn is high, the first switch tube Q1 is turned on; when the second logic control signal vinn is low, the first switch tube Q1 is turned off.

[0044] Specifically, the second switch tube Q2 is used to receive the first logic control signal vinp output by the first inverter inv1. When the first logic control signal vinp is high, the second switch tube Q2 is turned on; when the first logic control signal vinp is low, the second switch tube Q2 is turned off.

[0045] Specifically, the voltage divider unit includes: a first resistor R1, a second resistor R2, and a third resistor R3; wherein the connection state of the first resistor R1 is related to the on / off state of the first switch Q1, and the connection state of the second resistor R2 is related to the on / off state of the second switch Q2. Specifically, when the first switch Q1 is on and the second switch Q2 is off, the branch containing the first resistor R1 is on and the branch containing the second resistor R2 is off, and the first resistor R1 and the third resistor R3 perform the voltage division process; when the first switch Q1 is off and the second switch Q2 is on, the branch containing the first resistor R1 is off and the branch containing the second resistor R2 is on, and the second resistor R2 and the third resistor R3 perform the voltage division process.

[0046] According to some embodiments of the present application, the inverting output module 130 includes: a second inverter inv2 and a third inverter inv3. Furthermore, the specific connection relationship between the second inverter inv2 and the third inverter inv3 is further described.

[0047] Specifically, the input end of the second inverter inv2 serves as the inverting input end 131, and the inverting input end 131 is connected to the DC coupling output end 121C; the input end of the third inverter inv3 is connected to the output end of the second inverter inv2, and the output end of the third inverter inv3 serves as the inverting output end 132, and the inverting output end 132 is used to output the target level transfer signal Vout.

[0048] Furthermore, the functions implemented by the second inverter inv2 and the third inverter inv3 are further described.

[0049] Specifically, the logical expressions of the second inverter inv2 and the third inverter inv3 are both: ; The logical operation performed by the second inverter inv2 and the third inverter inv3 is: invert the input A to obtain the output Y.

[0050] Specifically, in an embodiment of the present application, when the coupling signal input to the second inverter inv2 is greater than the threshold voltage Vth (Vth=VCC / 2), it is equivalent to inputting a high level to the second inverter inv2, and the second inverter inv2 inverts the high level and outputs a low level; when the coupling signal input to the second inverter inv2 is less than the threshold voltage Vth (Vth=VCC / 2), it is equivalent to inputting a low level to the second inverter inv2, and the second inverter inv2 inverts the low level and outputs a high level.

[0051] Specifically, in the embodiment of the present application, when the second inverter inv2 outputs a high level to the third inverter inv3, the third inverter inv3 inverts the high point and outputs a low-level target level transfer signal Vout; when the second inverter inv2 outputs a low level to the third inverter inv3, the third inverter inv3 inverts the low level and outputs a high-level target level transfer signal Vout.

[0052] According to the level shifting circuit 100 provided in the embodiment of the first aspect of the present application, through the mutual cooperation of the logic control module 110, the AC / DC coupling module 120 and the inverting output module 130, the control method of the level shifting circuit 100 provided in the embodiment of the present application is executed to realize the level shifting function for both the input AC signal and the DC signal, so that the level shifting circuit 100 realizes the level shifting function for both the input AC signal and the DC signal through AC coupling and DC coupling.

[0053] It should be emphasized that the current common high-speed level conversion circuit is basically based on Figure 1 The circuit architecture of the level conversion circuit shown in the figure is improved, for example: connecting PMOS or NMOS tubes in series, using low-voltage NMOS tubes, adding bias voltage, etc. Although the level transfer speed has been improved to a certain extent, it is still not fast enough, and the problems of long delay and duty cycle imbalance are still not solved. Figure 2 The circuit shown uses AC coupling to implement the level shifting function. This technology achieves high speed, low latency and good duty cycle. Figure 2 The capacitive reactance of the capacitor is Xc=1 / (2πfC); the higher the AC signal frequency, the smaller the capacitive reactance; the lower the AC signal frequency, the larger the capacitive reactance. Therefore, this technology can only support the conversion of high-speed signals, that is, it only supports the conversion of high-speed signals with a signal period less than the time constant RC. For low-speed or DC levels, this structure is powerless. However, the present application implements an ultra-high-speed level shifting circuit 100 that combines AC coupling and DC coupling, solving the problems of long delay, low speed, and duty cycle imbalance existing in current level shifting circuits, and can realize level shifting functions for high-frequency AC signals, low-frequency AC signals, and DC signals based on this level shifting circuit.

[0054] Those skilled in the art will understand that the circuit structure shown in the figure does not constitute a limitation on the embodiments of the present invention, and may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0055] Those skilled in the art will understand that the circuit structure and application scenarios described in the embodiments of the present invention are intended to more clearly illustrate the technical solutions of the embodiments of the present invention, and do not constitute a limitation on the technical solutions provided by the embodiments of the present invention. Those skilled in the art will know that with the evolution of circuit structures and the emergence of new application scenarios, the technical solutions provided by the embodiments of the present invention are also applicable to similar technical problems.

[0056] Based on the above system structure, various embodiments of the control method of the level shifting circuit 100 of the present application are proposed below.

[0057] Second, as Figure 5 As shown, the control method of the level shift circuit can be applied to Figure 3 In the level shift circuit shown, the level shift circuit includes: a logic control module, an AC / DC coupling module, and an inverting output module; the AC / DC coupling module includes: a DC coupling unit and an AC coupling unit; the control method of the level shift circuit may include but is not limited to steps S110 to S120.

[0058] Step S110: When the enable signal is at a high level, the logic control module performs logic judgment processing based on the enable signal and the input signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, determines the on / off state of the branch where the AC coupling unit is located, controls the DC coupling unit to perform routing and voltage division processing, and outputs the coupling signal to the inverting output module; wherein the input signal is a DC signal or an AC signal.

[0059] Step S120: the inverting output module performs inverting processing on the coupled signal and outputs a target level-shifted signal.

[0060] Through steps S110 to S120, during the operation of the level shifting circuit, when the enable signal is at a high level, the logic control module performs logic judgment processing based on the enable signal and the input signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, determines the on / off state of the branch where the AC coupling unit is located, controls the DC coupling unit to perform path selection and voltage division processing, and outputs the coupled signal to the inverting output module; wherein the input signal is a DC signal or an AC signal; then, the inverting output module inverts the coupled signal and outputs the target level shifted signal; in this way, a low-latency, high-speed, and good duty cycle level shifting function can be achieved for both the input DC signal and the AC signal. That is, the embodiment of the present application can achieve a low-latency, high-speed, and good duty cycle level shifting function for both the AC signal and the DC signal by combining the AC coupling unit and the DC coupling unit.

[0061] According to some embodiments of the present application, step S110 is further described, wherein the logic control module performs logic judgment processing based on the enable signal and the input signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, determines the on / off state of the branch where the AC coupling unit is located, controls the DC coupling unit to perform routing and voltage division processing, and outputs the coupling signal to the inverting output module, including but not limited to steps S111 and S112.

[0062] Step S111: When the input signal is a DC signal, the logic control module performs a first logic operation based on the high-level enable signal and the DC signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, disconnects the branch where the AC coupling unit is located, and controls the DC coupling unit to perform a first voltage division process to output the coupled signal to the inverting output module.

[0063] Step S112: When the input signal is an AC signal, the logic control module performs a second logic operation based on the high-level enable signal and the AC signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, turns on the branch where the AC coupling unit is located, controls the AC coupling unit and the DC coupling unit to perform a second voltage division process, and outputs a coupled signal to the inverting output module.

[0064] Specifically, the input DC signal may be a high level or a low level, and the input AC signal may be a high frequency AC signal or a low frequency AC signal.

[0065] Specifically, the input AC signal includes: In the embodiment of the present application, a level shift function is implemented for the input DC signal through step S111, and a level shift function is implemented for the input AC signal through step S112.

[0066] Take an example, combined with Figure 4 The working principle of the circuit for implementing the level shifting function on the DC signal through step S111 is further explained.

[0067] Example 1: When the enable signal en is at a high level, the input signal Vin is a DC signal, and the DC signal is at a low level, the logic control module 110 performs a first logic operation based on the high-level enable signal en and the DC signal, including: first, the NAND logic gate nand2 performs a logic operation on the high-level enable signal en and the low-level DC signal to obtain a high level, and outputs the high level to the first inverter inv1 and the AND logic gate and2 respectively; then, the first inverter inv1 performs an inversion operation on the high level and outputs the first logic control signal vinp as a low level; at the same time, the AND logic gate and2 performs a logic operation on the high-level enable signal en and the high level output by the AND logic gate and2 to output the second logic control signal vinn as a high level. A first logic control signal vinp and a second logic control signal vinn are output to the AC / DC coupling module 120. Since the input signal Vin is a DC signal and the AC coupling unit 122 has the property of blocking DC and passing AC, the branch containing the AC coupling unit 122 is disconnected. The low-level first logic control signal vinp controls the second switch Q2 to be turned off, thereby disconnecting the branch containing the second resistor R2. The high-level second logic control signal vinn controls the first switch Q1 to be turned on, thereby connecting the branch containing the first resistor R1. The first resistor R1 and the third resistor R3 perform voltage division. At this time, the voltage value of the coupling signal vop is R1 / (R1+R3). By properly setting the resistance values ​​of the first resistor R1 and the third resistor R3, R1 / (R1+R3)=(VCC-VDD) / 2, that is, vop=(VCC-VDD) / 2. The coupling signal vop is output to the inverting output module 130. Since vop = (VCC - VDD) / 2 is less than the threshold voltage Vth of the second inverter inv2 (Vth = VCC / 2), it is equivalent to inputting a low level to the second inverter inv2. The second inverter inv2 inverts the low level and outputs a high level to the third inverter inv3. The third inverter inv3 then inverts the high level and outputs a low level. That is, the target level transfer signal Vout output by the third inverter inv3 is a low level.

[0068] Example 2: When the enable signal en is at a high level, the input signal Vin is a DC signal, and the DC signal is at a high level, the logic control module 110 performs a first logic operation based on the high-level enable signal en and the DC signal, including: first, the NAND logic gate nand2 performs a logic operation on the high-level enable signal en and the high-level DC signal to obtain a low level, and outputs the low level to the first inverter inv1 and the AND logic gate and2 respectively; then, the first inverter inv1 performs an inversion operation on the low level and outputs the first logic control signal vinp as a high level; at the same time, the AND logic gate and2 performs a logic operation on the high-level enable signal en and the low level output by the AND logic gate and2 to output the second logic control signal vinn as a low level. A first logic control signal vinp and a second logic control signal vinn are output to the AC / DC coupling module 120. Since the input signal Vin is a DC signal and the AC coupling unit 122 blocks DC and passes AC, the branch containing the AC coupling unit 122 is disconnected. A high-level first logic control signal vinp turns on the second switch Q2, thereby turning on the branch containing the second resistor R2. A low-level second logic control signal vinn turns off the first switch Q1, thereby disconnecting the branch containing the first resistor R1. The voltage of the coupling signal vop is then divided by the second and third resistors R2 and R3. By properly setting the resistance values ​​of the second and third resistors R2 and R3, R2 / (R2+R3)=(VCC+VDD) / 2, i.e., vop=(VCC+VDD) / 2. The coupling signal vop is output to the inverting output module 130. Since vop = (VCC + VDD) / 2 is greater than the threshold voltage Vth of the second inverter inv2 (Vth = VCC / 2), it is equivalent to inputting a high level to the second inverter inv2. The second inverter inv2 inverts the high level and outputs a low level to the third inverter inv3. The third inverter inv3 then inverts the low level and outputs a high level. That is, the target level transfer signal Vout output by the third inverter inv3 is a high level.

[0069] Through Example 1 and Example 2 of step S111, the embodiment of the present application realizes the level shifting function of the DC signal by forming a DC coupling path through the first resistor R1, the second resistor R2, the third resistor R3, the first switch tube Q1, and the second switch tube Q2.

[0070] Take an example, combined with Figure 4 The working principle of the circuit for implementing the level shifting function on the AC signal in step S112 is further explained.

[0071] Example 3: When the enable signal en is at a high level, the input signal Vin is an AC signal, and the AC signal jumps from a low level to a high level instantaneously, the logic control module 110 performs a first logic operation based on the high-level enable signal en and the DC signal, including: first, the NAND logic gate nand2 performs a logic operation on the high-level enable signal en and the high-level DC signal to obtain a low level, and outputs the low level to the first inverter inv1 and the AND logic gate and2 respectively; then, the first inverter inv1 performs an inverting operation on the low level and outputs the first logic control signal vinp as a high level, that is, the first logic control signal vinp also jumps from a low level to a high level along with the AC signal; due to the AC coupling effect of the coupling capacitor C, Because the voltage across a capacitor cannot change suddenly, the voltage of the coupling signal vop will instantly jump to increase the voltage of VDD. That is, the coupling signal vop instantly changes from the original voltage of (VCC-VDD) / 2 to (VCC-VDD) / 2+VDD=(VCC+VDD) / 2. The coupling signal vop is output to the inverting output module 130. Since vop=(VCC+VDD) / 2 is greater than the threshold voltage Vth of the second inverter inv2 (Vth=VCC / 2), it is equivalent to inputting a high level to the second inverter inv2. After being inverted by the second inverter inv2 and the third inverter inv3, a high level is output. That is, the target level-shifted signal Vout output by the third inverter inv3 is a high level. Simultaneously, AND logic gate and2 processes the high-level enable signal en and the low-level output of NAND logic gate nand2, outputting a low-level second logic control signal vinn. Consequently, the high-level first logic control signal vinp turns on the second switch Q2, while the low-level second logic control signal vinn turns off the first switch Q1. The voltage is then divided by the second resistor R2 and the third resistor R3. After voltage division by the second and third resistors R2 and R3, the coupled signal vop = (VCC + VDD) / 2. This DC coupling path ensures that the voltage of the coupled signal vop remains stably at (VCC + VDD) / 2, effectively resolving the issue in traditional AC coupling structures where the time constant τ (τ = RC) causes gradual charge leakage, ultimately preventing level shifting of low-speed signals.

[0072] Example 4: When the enable signal en is at a high level, the input signal Vin is an AC signal, and the AC signal jumps from a high level to a low level instantaneously, the logic control module 110 performs a first logic operation based on the high-level enable signal en and the DC signal, including: first, the NAND logic gate nand2 performs a logic operation on the high-level enable signal en and the low-level DC signal to obtain a high level, and outputs the high level to the first inverter inv1 and the AND logic gate and2 respectively; then, the first inverter inv1 performs an inverting operation on the high level and outputs the first logic control signal vinp as a low level; that is, the first logic control signal vinp also jumps from a high level to a low level along with the AC signal; due to the AC coupling effect of the coupling capacitor C, Because the voltage across a capacitor cannot change suddenly, the voltage of the coupling signal vop will instantly jump to lower the voltage of VDD. That is, the coupling signal vop will instantly change from the original voltage of (VCC + VDD) / 2 to (VCC + VDD) / 2-VDD = (VCC - VDD) / 2. The coupling signal vop is then output to the inverting output module 130. Since vop = (VCC - VDD) / 2 is less than the threshold voltage Vth of the second inverter inv2 (Vth = VCC / 2), this is equivalent to inputting a low level to the second inverter inv2. After being inverted by the second inverter inv2 and the third inverter inv3, a low level is output. That is, the target level-shifted signal Vout output by the third inverter inv3 is a low level. Simultaneously, AND logic gate and2 processes the high-level enable signal en and the high-level output of NAND logic gate nand2, outputting a high-level second logic control signal vinn. Consequently, the low-level first logic control signal vinp turns off the second switch Q2, while the high-level second logic control signal vinn turns on the first switch Q1. Voltage is then divided by first resistor R1 and third resistor R3. After voltage division by first resistor R1 and third resistor R3, the coupled signal vop = (VCC - VDD) / 2. This DC coupling path ensures that the voltage of the coupled signal vop remains stable at (VCC - VDD) / 2, effectively resolving the issue in traditional AC coupling structures where the time constant τ (τ = RC) causes gradual charge leakage, ultimately preventing level shifting of low-speed signals.

[0073] The embodiment of the present application implements the level shifting function of the AC signal through Example 3 and Example 4 of step S112.

[0074] According to some embodiments of the present application, the control method of the level transfer circuit 100 of the embodiment of the present application also includes: step S130: when the enable signal en is at a low level, the logic control module 110 performs a third logic judgment processing based on the low-level enable signal en, and outputs a first logic control signal vinp and a second logic control signal vinn, both of which are low levels, to the AC / DC coupling module 120, so that the coupling signal output by the AC / DC coupling module 120 is equal to the voltage value output by the second power supply VCC, and the inverting output module 130 performs inverting processing on the coupling signal and outputs a high-level signal.

[0075] Take an example, combined with Figure 4 The specific process of step S130 is described.

[0076] Example 5: When the enable signal en is at a low level, the first logic control signal vinp and the second logic control signal vinn are both at a low level, and the first switch tube Q1 is turned off. The voltage of the coupling signal vop is pulled up to VCC by the third resistor R3, and the output terminal Vout of the third inverter inv3 outputs a high level, that is, the output target level transfer signal Vout is at a high level; and the entire level transfer circuit 100 does not consume static current.

[0077] In summary, the control method for the level shifter circuit 100 of the present embodiment effectively implements level shifting for low-frequency signals, high-frequency signals across the entire frequency range, and DC signals through AC coupling and DC coupling. Furthermore, because the coupled signal vop transitions instantaneously with the voltage of vinp through the AC coupling effect when the input signal vin changes, it achieves a low-latency, high-speed, and good-duty-cycle level shifting effect.

[0078] In a third aspect, an embodiment of the present application provides an electronic device, comprising a level transfer circuit as in any one of the embodiments of the first aspect.

[0079] An electronic device provided according to an embodiment of the present application includes a level shifting circuit provided according to an embodiment of the present application, the level shifting circuit including: a logic control module, an AC / DC coupling module, and an inverting output module. During operation of the level shifting circuit, the control method of the level shifting circuit provided according to the embodiment of the present application can be implemented to achieve a low-latency, high-speed, and good-duty-cycle level shifting function for both input DC and AC signals. In other words, the electronic device provided according to the embodiment of the present application can achieve a low-latency, high-speed, and good-duty-cycle level shifting function for both AC and DC signals by combining an AC coupling unit with a DC coupling unit.

[0080] As can be seen, the present application is based on an ultra-high-speed level-shifting circuit using AC coupling and DC coupling. AC coupling can achieve low-latency, high-speed, and good-duty-cycle level-shifting functionality, while DC coupling can also achieve level-shifting functionality for low-frequency and DC signals. By combining AC coupling and DC coupling, level-shifting functionality can be achieved for low-frequency signals, high-frequency signals across the full frequency range, and DC signals, with low latency, high speed, and a good duty cycle.

[0081] It should be noted that since the electronic device of this embodiment can implement the control method of the level transfer circuit of any previous embodiment, the electronic device of this embodiment and the control method of the level transfer circuit of any previous embodiment have the same technical principles and the same technical effects. In order to avoid redundancy, they will not be repeated here.

[0082] The above is a specific description of the preferred implementation of the present application, but the present application is not limited to the above implementation mode. Technical personnel familiar with the field can also make various equivalent modifications or substitutions without violating the spirit of the present application. These equivalent modifications or substitutions are all included in the scope defined by the present application.

Claims

1. A level shift circuit, characterized in that: include: A logic control module, comprising a first signal input terminal, a second signal input terminal, a first control output terminal, a second control output terminal and a first power input terminal; The first signal input terminal is connected to an input signal source, the second signal input terminal is connected to an enable signal source, and the first power input terminal is connected to a first power source; An AC / DC coupling module includes: a DC coupling unit and an AC coupling unit; wherein the DC coupling unit includes a first control input terminal, a second control input terminal, a DC coupling output terminal, and a second power supply input terminal; the first control input terminal is connected to the first control output terminal, the second control input terminal is connected to the second control output terminal, and the second power supply input terminal is connected to the second power supply; the AC coupling unit includes an AC coupling input terminal and an AC coupling output terminal; the AC coupling input terminal is connected to the first control output terminal; and the AC coupling output terminal is connected to the DC coupling output terminal; The inverting output module includes an inverting input terminal, an inverting output terminal and a third power input terminal; the inverting input terminal is connected to the DC coupling output terminal, the inverting output terminal is used to output the target level transfer signal, and the third power input terminal is connected to the second power supply.

2. The level shift circuit according to claim 1, wherein: The logic control module includes: A NAND logic gate, wherein a first input terminal of the NAND logic gate is connected to an input signal source, and a second input terminal of the NAND logic gate is connected to an enable signal source; wherein the input signal source is used to generate an input signal; and the enable signal source is used to generate an enable signal; a first inverter, wherein the input end of the first inverter is connected to the output end of the NAND logic gate; the output end of the first inverter is the first control output end, and the first control output end is connected to the AC coupling input end; An AND logic gate, wherein a first input terminal of the AND logic gate is connected to an output terminal of the NAND logic gate; a second input terminal of the AND logic gate is connected to the enable signal source; and an output terminal of the AND logic gate is the second control output terminal, and the second control output terminal is connected to the second control input terminal of the DC coupling unit.

3. The level shift circuit according to claim 2, wherein: The AC coupling unit includes: a coupling capacitor, one end of the coupling capacitor being the AC coupling input end, and the other end of the coupling capacitor being the AC coupling output end; the AC coupling input end being connected to the first control output end of the first inverter; and the AC coupling output end being connected to the DC coupling output end of the DC coupling unit.

4. The level shift circuit according to claim 3, wherein: The DC coupling unit includes: The voltage dividing unit includes: a first resistor, a second resistor, and a third resistor; one end of the third resistor is connected to the second power supply as a second power supply end, and the other end of the third resistor is connected to the inverting input end as the DC coupling output end; a first switching transistor, wherein the gate of the first switching transistor is connected to the second control output terminal of the AND logic gate, the source of the first switching transistor is grounded, and the drain of the first switching transistor is connected between the AC coupling output terminal and the DC coupling output terminal of the coupling capacitor via the first resistor; a second switching tube, wherein the gate of the second switching tube is connected to the first control output terminal of the first inverter, the source of the second switching tube is grounded, and the drain of the second switching tube is connected between the AC coupling output terminal and the DC coupling output terminal of the coupling capacitor through the second resistor.

5. The level shift circuit according to claim 3, wherein: The inverting output module includes: a second inverter, wherein an input terminal of the second inverter serves as the inverting input terminal, and the inverting input terminal is connected to the DC coupling output terminal; A third inverter, wherein the input end of the third inverter is connected to the output end of the second inverter, the output end of the third inverter serves as the inverting output end, and the inverting output end is used to output the target level shift signal.

6. The level shift circuit according to claim 4, wherein: The first switch tube and the second switch tube are both N-channel metal oxide semiconductor field effect transistors.

7. A control method for a level shift circuit, characterized in that: Applicable to the level shift circuit according to claim 1, the level shift circuit comprises: a logic control module, an AC / DC coupling module, and an inverting output module; the AC / DC coupling module comprises: a DC coupling unit and an AC coupling unit; The method comprises: When the enable signal is at a high level, the logic control module performs logic judgment processing based on the enable signal and the input signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, determines the on / off state of the branch where the AC coupling unit is located, controls the DC coupling unit to perform path selection and voltage division processing, and outputs a coupling signal to the inverting output module; wherein the input signal is a DC signal or an AC signal; The inverting output module performs inverting processing on the coupled signal and outputs a target level-shifted signal.

8. The control method of the level shift circuit according to claim 7, wherein: The logic control module performs logic judgment processing according to the enable signal and the input signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, determines the on / off state of the branch where the AC coupling unit is located, controls the DC coupling unit to perform path selection and voltage division processing, and outputs a coupling signal to the inverting output module, including: When the input signal is a DC signal, the logic control module performs a first logic operation based on the high-level enable signal and the DC signal, outputs a first logic control signal and a second logic control signal to the AC / DC coupling module, disconnects the branch where the AC coupling unit is located, and controls the DC coupling unit to perform a first voltage division process and output the coupled signal to the inverting output module; When the input signal is an AC signal, the logic control module performs a second logic operation based on the high-level enable signal and the AC signal, outputs the first logic control signal and the second logic control signal to the AC / DC coupling module, turns on the branch where the AC coupling unit is located, controls the AC coupling unit and the DC coupling unit to perform a second voltage division process, and outputs a coupling signal to the inverting output module.

9. The control method of the level shift circuit according to claim 7, wherein: The method further comprises: When the enable signal is at a low level, the logic control module performs a third logic judgment process based on the low-level enable signal, and outputs a first logic control signal and a second logic control signal, both of which are low levels, to the AC / DC coupling module, so that the coupled signal output by the AC / DC coupling module is equal to the voltage value output by the second power supply. The inverting output module inverts the coupled signal and outputs a high-level signal.

10. An electronic device, characterized in that: The method comprises the level shifting circuit according to any one of claims 1 to 6.

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