Communication interface circuit and chip

Abstract

The invention relates to a communication interface circuit and a chip. The communication interface circuit comprises: a power supply for providing a supply voltage; the voltage drop module is used for carrying out voltage reduction processing on the power supply voltage to output power supply voltage; the trigger module is used for receiving the communication signal and outputting a first level signal according to the communication signal under the action of the power supply voltage and the grounding voltage provided by the reference ground; the first level signal comprises a power supply voltage or a grounding voltage; the difference value between the power supply voltage and the high-level lower limit value of the communication signal is smaller than the sum of the step-down value and the preset value; the step-down value is the difference between the power supply voltage and the power supply voltage, and the preset value is related to the trigger module; the level conversion module is used for converting the first level signal into a second level signal under the action of the power supply voltage; wherein the voltage value ranges of the second level signal and the communication signal are different. According to the communication interface circuit, communication signals can be converted from a low voltage domain to a high voltage domain only by arranging one power supply, and the structure is simple.

Description

Technical Field

[0001] This application relates to the field of level conversion technology, and in particular to a communication interface circuit and chip. Background Technology

[0002] Different chips may operate at different voltages. When chips with different operating voltages communicate with each other, it is usually necessary to first convert the communication signal level sent by the sender into a level that the receiver can recognize in order to achieve communication between the two.

[0003] Current chips typically require additional interfaces to connect to the power supply of the transmitter, which leads to complex circuit structures. Summary of the Invention

[0004] Therefore, it is necessary to provide a communication interface circuit and chip with a simple structure.

[0005] In a first aspect, this application provides a communication interface circuit, including:

[0006] A power supply is used to provide power voltage.

[0007] A voltage drop module, connected to the power supply, is used to step down the power supply voltage to output a supply voltage;

[0008] A trigger module, connected to the voltage drop module and a reference ground, is used to receive communication signals and to output a first-level signal based on the communication signals under the influence of the power supply voltage and the ground voltage provided by the reference ground; wherein the first-level signal includes the power supply voltage or the ground voltage; the difference between the power supply voltage and the high-level lower limit of the communication signal is less than the sum of the voltage drop value and a preset value; wherein the voltage drop value is the difference between the power supply voltage and the power supply voltage, and the preset value is related to the trigger module;

[0009] A level conversion module is connected to the trigger module and the power supply respectively, and is used to convert the first level signal into a second level signal under the action of the power supply voltage; wherein the voltage range of the second level signal is different from that of the communication signal.

[0010] In one embodiment, the voltage drop module includes at least one diode;

[0011] When there is only one diode, the anode of the diode is connected to the power supply, and the cathode of the diode is connected to the trigger module.

[0012] When the number of diodes is m, where m is a positive integer greater than 1, the m diodes are connected in series, wherein the anode of the first diode is connected to the power supply, and the cathode of the mth diode is connected to the trigger module;

[0013] The diode is used to step down the power supply voltage to output the supply voltage.

[0014] In one embodiment, the voltage drop module includes: at least one first transistor;

[0015] When the number of the first transistor is one, the first terminal of the first transistor is connected to the power supply, and the second terminal of the first transistor is connected to the trigger module and the control terminal of the first transistor.

[0016] When the number of the first transistors is n, where n is a positive integer greater than 1, the n first transistors are connected in series, and the second terminal of each first transistor is connected to the control terminal. The second terminal of the (n-1)th first transistor is also connected to the first terminal of the nth first transistor. The first terminal of the first first transistor is connected to the power supply, and the second terminal of the nth first transistor is connected to the trigger module.

[0017] The first transistor is used to step down the power supply voltage to output the power supply voltage.

[0018] In one embodiment, the triggering module includes:

[0019] The second transistor has a first terminal connected to the voltage drop module and a second terminal connected to the level conversion module. The control terminal of the second transistor is used to receive the communication signal.

[0020] The third transistor has its first terminal connected to the level conversion module and the second terminal of the second transistor, and its second terminal connected to the reference ground. The control terminal of the third transistor is used to receive the communication signal.

[0021] The common connection terminal of the second transistor and the third transistor is also used to output the first level signal, which is opposite in phase to the communication signal.

[0022] In one embodiment, the preset value is the conduction threshold of the second transistor.

[0023] In one embodiment, the triggering module includes:

[0024] The comparator is connected to the voltage drop module, the reference ground, and the level conversion module respectively, and is used to output the first level signal according to the communication signal under the action of the supply voltage and the ground voltage; the set threshold of the comparator is less than the supply voltage.

[0025] In one embodiment, the preset value is zero.

[0026] In one embodiment, the level conversion module includes:

[0027] An inverter, connected to the power supply, the trigger module, and the reference ground respectively, is used to invert the first level signal under the action of the power supply voltage and output a second level signal, wherein the set threshold of the inverter is less than the power supply voltage.

[0028] In one embodiment, the communication interface circuit further includes:

[0029] The feedback pull-up module has its input terminal connected to the level conversion module, its output terminal connected to the voltage drop module and the trigger module, its first power supply terminal connected to the power supply, and its second power supply terminal grounded. The feedback pull-up module is used to output the power supply voltage to the trigger module when the second level signal is a first voltage value.

[0030] In one embodiment, the feedback pull-up module includes:

[0031] The fourth transistor has its control terminal connected to the level conversion module, its first terminal connected to the power supply, and its second terminal connected to the voltage drop module and the trigger module, respectively.

[0032] A capacitor, the first terminal of which is connected to the second terminal of the fourth transistor, and the second terminal of which is grounded.

[0033] Secondly, this application also provides a communication interface circuit, including: a power supply, at least one first transistor, a flip-flop, and an inverter;

[0034] Wherein, when there is only one first transistor, the first terminal of the first transistor is connected to the power supply, and the second terminal of the first transistor is connected to the flip-flop and the control terminal of the first transistor; when there are n first transistors, where n is a positive integer greater than 1, the n first transistors are connected in series, and the second terminal of each first transistor is connected to the corresponding control terminal, the second terminal of the (n-1)th first transistor is also connected to the first terminal of the nth first transistor, the first terminal of the first first transistor is connected to the power supply, and the second terminal of the nth first transistor is connected to the flip-flop;

[0035] The input terminal of the flip-flop is used to receive communication signals, the output terminal of the flip-flop is connected to the input terminal of the inverter, and the second power supply terminal of the flip-flop is grounded.

[0036] The output terminal of the inverter is used to output a second level signal. The first power supply terminal of the inverter is connected to the power supply, and the second power supply terminal of the inverter is grounded.

[0037] Thirdly, this application also provides a communication interface circuit, including: a power supply, at least one diode, a flip-flop, and an inverter;

[0038] Where the number of diodes is one, the anode of the diode is connected to the power supply, and the cathode of the diode is connected to the trigger; where the number of diodes is m, where m is a positive integer greater than 1, the m diodes are connected in series, wherein the anode of the first diode is connected to the power supply, and the cathode of the mth diode is connected to the trigger.

[0039] The input terminal of the flip-flop is used to receive communication signals, the output terminal of the flip-flop is connected to the input terminal of the inverter, and the second power supply terminal of the flip-flop is grounded.

[0040] The output terminal of the inverter is used to output a second level signal. The first power supply terminal of the inverter is connected to the power supply, and the second power supply terminal of the inverter is grounded.

[0041] Fourthly, this application also provides a communication interface circuit, including: a power supply, at least one first transistor, a second transistor, a third transistor, a fourth transistor, a capacitor, and an inverter;

[0042] When there is only one first transistor, the first terminal of the first transistor is connected to the power supply, and the second terminal of the first transistor is connected to the control terminal of the first transistor, the first terminal of the second transistor, the second terminal of the fourth transistor, and the first terminal of the capacitor. When there are n first transistors, the n first transistors are connected in series, where n is a positive integer greater than 1. The control terminal of each first transistor is connected to its corresponding second terminal, the second terminal of the (n-1)th first transistor is also connected to the first terminal of the nth transistor, the first terminal of the first first transistor is connected to the power supply, and the second terminal of the nth first transistor is also connected to the first terminal of the second transistor, the second terminal of the fourth transistor, and the first terminal of the capacitor.

[0043] The second terminal of the second transistor is connected to the first terminal of the third transistor and the input terminal of the inverter, respectively; the control terminal of the second transistor is connected to the control terminal of the third transistor; the second terminal of the third transistor is grounded.

[0044] The first terminal of the fourth transistor is connected to the power supply, and the control terminal of the fourth transistor is connected to the output terminal of the inverter.

[0045] The first power supply terminal of the inverter is connected to the power supply, and the second power supply terminal of the inverter is grounded.

[0046] Fifthly, this application also provides a communication interface circuit, including: a power supply, at least one diode, a second transistor, a third transistor, a fourth transistor, a capacitor, and an inverter;

[0047] When there is one diode, the anode of the diode is connected to the power supply, and the cathode of the diode is connected to the first terminal of the second transistor, the second terminal of the fourth transistor, and the first terminal of the capacitor, respectively. When there are m diodes, the m diodes are connected in series, where m is a positive integer greater than 1. The anode of the first diode is connected to the power supply, and the cathode of the nth diode is connected to the first terminal of the second transistor, the second terminal of the fourth transistor, and the first terminal of the capacitor.

[0048] The second terminal of the second transistor is connected to the first terminal of the third transistor and the input terminal of the inverter, respectively; the control terminal of the second transistor is connected to the control terminal of the third transistor; the second terminal of the third transistor is grounded.

[0049] The first terminal of the fourth transistor is connected to the power supply, and the control terminal of the fourth transistor is connected to the output terminal of the inverter.

[0050] The first power supply terminal of the inverter is connected to the power supply, and the second power supply terminal of the inverter is grounded.

[0051] Sixthly, this application also provides a chip that includes the communication interface circuit provided in any of the above embodiments.

[0052] In the aforementioned communication interface circuit and chip, the communication interface circuit includes a power supply, a voltage drop module, a trigger module, and a level conversion module. When communicating between chips operating at different voltages, the voltage drop module first reduces the power supply voltage to the supply voltage and outputs the supply voltage to the trigger module. Since the difference between the supply voltage and the lower limit of the high-level communication signal is less than the sum of the voltage drop value and a preset value (i.e., the lower limit of the high-level communication signal is greater than the difference between the supply voltage and the preset value), the trigger module, under the influence of the supply voltage, can accurately identify the high and low levels of the communication signal in the low-voltage domain and generate a first-level signal based on the level state of the communication signal. The level conversion module then converts the first-level signal into a second-level signal in the high-voltage domain, thus realizing communication between chips operating at different voltages. Furthermore, the communication interface circuit provided in this embodiment only requires one power supply, i.e., a high-voltage domain power supply, and does not require an additional interface for connection to the low-voltage domain power supply, resulting in a simple structure and reduced costs. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 One of the schematic diagrams of a communication interface circuit provided in one embodiment;

[0055] Figure 2 A second schematic diagram of a communication interface circuit provided in one embodiment;

[0056] Figure 3 A third schematic diagram of a communication interface circuit provided in one embodiment;

[0057] Figure 4 Schematic diagram four of a communication interface circuit provided in one embodiment;

[0058] Figure 5 Fifth schematic diagram of a communication interface circuit provided in one embodiment;

[0059] Figure 6 A schematic diagram of a communication interface circuit provided in one embodiment;

[0060] Figure 7 Schematic diagram seven of a communication interface circuit provided in one embodiment;

[0061] Figure 8 Eighth schematic diagram of a communication interface circuit provided in one embodiment;

[0062] Figure 9 Schematic diagram nine of a communication interface circuit provided in one embodiment;

[0063] Figure 10 This is the tenth schematic diagram of a communication interface circuit provided in one embodiment.

[0064] Explanation of reference numerals in the attached figures:

[0065] 100 - Power supply, 200 - Voltage drop module, 300 - Trigger module, 400 - Level conversion module, 500 - Feedback pull-up module. Detailed Implementation

[0066] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0068] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first transistor may be referred to as a second transistor, and similarly, a second transistor may be referred to as a first transistor. Both the first transistor and the second transistor are transistors, but they are not the same transistor.

[0069] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0070] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0071] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0072] In one embodiment, this application provides a communication interface circuit, such as... Figure 1 As shown, it includes a power supply 100, a voltage drop module 200, a trigger module 300, and a level conversion module 400. The voltage drop module 200 is connected to both the power supply 100 and the trigger module 300, and the level conversion module 400 is also connected to both the power supply 100 and the trigger module 300.

[0073] Power supply 100 is used to provide power supply voltage.

[0074] The voltage drop module 200 is used to step down the power supply voltage to output the power supply voltage.

[0075] The trigger module 300 receives communication signals and, under the influence of the power supply voltage and the ground voltage provided by the reference ground, outputs a first-level signal based on the communication signals. The first-level signal includes either the power supply voltage or the ground voltage. The communication signal can be a digital signal, and its voltage domain is smaller than the power supply voltage domain. The first-level signal can be in phase with or out of phase with the communication signal. The difference between the power supply voltage and the lower high-level limit of the communication signal is less than the sum of the voltage drop and a preset value. The voltage drop is the difference between the power supply voltage and the ground voltage, and the preset value is related to the trigger module.

[0076] The level conversion module 400 is used to convert a first-level signal into a second-level signal under the influence of the power supply voltage. The voltage range of the second-level signal differs from that of the communication signal. Specifically, the voltage range of the second-level signal is greater than that of the communication signal; that is, the second-level signal is in the high-voltage domain, while the communication signal is in the low-voltage domain.

[0077] In this embodiment, the communication interface circuit includes a power supply 100, a voltage drop module 200, a trigger module 300, and a level conversion module 400. When communicating between chips operating at different voltages, the voltage drop module 200 first reduces the power supply voltage provided by the power supply 100 to the supply voltage, and then outputs the supply voltage to the trigger module 300. Since the difference between the supply voltage and the lower limit of the high-level communication signal is less than the sum of the voltage drop value and a preset value (i.e., the lower limit of the high-level communication signal is greater than the difference between the supply voltage and the preset value), the trigger module 300, under the influence of the supply voltage, can accurately identify the high and low levels of the communication signal in the low-voltage domain and generate a first-level signal based on the level state of the communication signal. The level conversion module 400 then converts the first-level signal into a second-level signal in the high-voltage domain, thus realizing communication between chips operating at different voltages. Furthermore, the communication interface circuit provided in this embodiment only requires one power supply 100 (high-voltage domain power supply) and does not require an additional interface for connection to the low-voltage domain power supply, resulting in a simple structure and reduced costs.

[0078] In one embodiment, such as Figures 2-3 As shown, the voltage drop module 200 includes at least one diode D1. When the number of diodes D1 is one, as... Figure 2 As shown, the anode of diode D1 is connected to the power supply, and the cathode of diode D1 is connected to the trigger module 300. Diode D1 is used to step down the power supply voltage to output the supply voltage. In the case where the voltage drop module 200 includes m diodes D1 (m is a positive integer greater than 1), as... Figure 3 As shown, multiple diodes D1 are connected in series between the power supply 100 and the trigger module 300. The anode of the first diode is connected to the power supply 100, and the cathode of the m-th diode is connected to the trigger module 300. The difference between the power supply voltage and the supply voltage is the product of the number of diodes D1 and the PN junction voltage drop of diodes D1. For example, if the power supply voltage is VCC, the PN junction voltage drop of diode D1 is 0.7V, and the number of diodes is n (n≥1), then the supply voltage is VCC-0.7n.

[0079] In one embodiment, such as Figures 4-5 As shown, the voltage drop module 200 includes at least one first transistor M1. When the number of first transistors M1 is one, as... Figure 4 As shown, the first terminal of the first transistor M1 is connected to the power supply 100, and the second terminal of the first transistor M1 is connected to the trigger module 300 and the control terminal of the first transistor M1. The first transistor M1 is used to step down the power supply voltage to output the supply voltage. In the case where the voltage drop module 200 includes n first transistors M1 (n is a positive integer greater than 1), as... Figure 5As shown, multiple first transistors M1 are connected in series between the power supply 100 and the trigger module 300. The first terminal of the first transistor is connected to the power supply 100, the second terminal of the nth transistor is connected to the trigger module 300, and the first terminal of one transistor is connected to the second terminal of another transistor. The difference between the power supply voltage and the supply voltage is the product of the number of first transistors M1 and the PN junction voltage drop of the body diode in the first transistor M1. For example, the first transistor M1 can be a PMOS transistor.

[0080] In one embodiment, the voltage drop module 200 may include at least one resistor. If the voltage drop module 200 includes multiple resistors, these resistors may be connected in series between the power supply 100 and the trigger module 300.

[0081] In one embodiment, the voltage drop module 200 may include a low-dropout linear stabilizer. The low-dropout linear stabilizer can convert the power supply voltage into a stable supply voltage.

[0082] In one embodiment, such as Figures 6-7 As shown, the trigger module 300 includes a second transistor M1 and a third transistor M3.

[0083] The first terminal of the second transistor M1 is connected to the voltage drop module 200. The second terminal of the second transistor M1 is connected to both the level conversion module 400 and the first terminal of the third transistor M3. The control terminal of the second transistor M1 is used to receive communication signals, and the second terminal of the third transistor M3 is connected to a reference ground. The control terminal of the third transistor M3 is also used to receive communication signals. The common connection terminal of the second transistor M1 and the third transistor M3 is also used to output a first-level signal, which is out of phase with the communication signal. For example, the second transistor M1 can be a PMOS transistor, and the third transistor M3 can be an NMOS transistor. The first terminal of the second transistor M1 can be the source, and the second terminal of the second transistor M1 can be the drain. The first terminal of the third transistor M3 can be the drain, and the second terminal of the third transistor M3 can be the source.

[0084] The preset value is the conduction threshold of the second transistor M1. That is, the difference between the power supply voltage and the lower high-level limit of the communication signal is less than the sum of the step-down voltage and the conduction threshold of the second transistor M1; in other words, the lower high-level limit of the communication signal is greater than the difference between the power supply voltage and the conduction threshold of the second transistor M1. Thus, when the communication signal PAD_INPUT is low, the second transistor M1 is turned on, and the potential at the common connection terminal of the second transistor M1 and the third transistor M3 is pulled up to the power supply voltage, resulting in a high-level first signal. As the communication signal PAD_INPUT changes from low to high, the third transistor M3 slowly turns on. When the voltage of the communication signal exceeds the difference between the power supply voltage and the conduction threshold of the second transistor M1, the second transistor M1 is turned off, and the potential at the common connection terminal is pulled down to ground, resulting in a low-level first signal. This achieves accurate identification and preliminary conversion of the high and low levels of the communication signal.

[0085] In one embodiment, such as Figure 8 As shown, the trigger module 300 includes a comparator SMIT. The comparator SMIT is connected to the voltage drop module 200, the reference ground, and the level conversion module 400, respectively, and is used to output a first level signal based on the communication signal under the influence of the supply voltage and the ground voltage. The first level signal is in phase with the communication signal. The set threshold of the comparator SMIT is less than the supply voltage. For example, the set threshold of the comparator SMIT can be 0.7 times the supply voltage, and the comparator can be a Schmitt trigger.

[0086] In this embodiment, the preset value is zero, meaning the difference between the power supply voltage and the lower limit of the high level of the communication signal is less than the step-down value. When the voltage value of the communication signal PAD_INPUT is greater than or equal to the set threshold of the comparator SMIT, the first level signal output by the comparator SMIT is the power supply voltage; when the voltage value of the communication signal PAD_INPUT is less than the set threshold of the comparator SMIT, the first level signal output by the comparator SMIT is the ground voltage. It can be understood that by setting the voltage drop module 200 to reduce the power supply voltage, the design difficulty of the set threshold of the comparator SMIT is reduced, and the comparator SMIT can accurately identify the high and low levels of the communication signal.

[0087] In one embodiment, such as Figures 6-7 As shown, the level conversion module 400 includes an inverter INV1. The inverter INV1 is connected to the power supply 100, the trigger module 300, and the reference ground, respectively, and is used to invert the first level signal under the influence of the power supply voltage to output a second level signal. The set threshold of the inverter INV1 is lower than the supply voltage to ensure that the inverter INV1 can accurately identify the high and low levels of the first level signal.

[0088] Furthermore, such as Figures 6-7 As shown, the communication interface circuit also includes a feedback pull-up module 500. The feedback pull-up module 500 is connected to the power supply 100, the voltage drop module 200, the trigger module 300, and the level conversion module 400, respectively, and is used to output the power supply voltage to the trigger module 300 when the second level signal is the first voltage value. The first voltage value can be the power supply voltage or the ground voltage.

[0089] Furthermore, such as Figures 6-7 As shown, the feedback pull-up module 500 includes a fourth transistor M4 and a capacitor C1. The first terminal of the fourth transistor M4 is connected to the power supply 100, the second terminal of the fourth transistor M4 is connected to the first terminal of the capacitor C1 and the trigger module 300, the control terminal of the fourth transistor M4 is connected to the level conversion module 400, and the second terminal of the capacitor is connected to a reference ground. For example, the fourth transistor M4 can be a PMOS transistor, and the first voltage value can be the ground voltage; alternatively, the fourth transistor M4 can be an NMOS transistor, and the first voltage value can be the power supply voltage.

[0090] Taking the fourth transistor M4 as a PMOS transistor as an example, when the communication signal PAD_INPUT is low, the second transistor M1 is turned on, and the potential of the common connection terminal of the second transistor M1 and the third transistor M3 is pulled up to the supply voltage. The first level signal is high, and the voltage value of the second level signal OUTPUT generated after passing through the level conversion module 400 is the ground voltage. The fourth transistor M4 is turned on, and the potential of the common connection terminal is pulled up to the power supply voltage. That is, the voltage value of the first level signal is the power supply voltage, which can provide a stable drive for the level conversion module 400. When the communication signal PAD_INPUT changes from low to high, the third transistor M3 slowly turns on, the second transistor M1 slowly turns off, and the potential of the common connection terminal is pulled down to the ground voltage. That is, the first level signal is low, and the voltage value of the second voltage signal OUTPUT generated after passing through the level conversion module 400 is the power supply voltage. The fourth transistor M4 is turned off.

[0091] In one embodiment, this application also provides a communication interface circuit, such as... Figure 9 As shown, it includes a power supply VCC, at least one first transistor M1, a flip-flop SMIT, and an inverter INV.

[0092] In the case of one first transistor M1, the first terminal of the first transistor M1 is connected to the power supply VCC, and the second terminal of the first transistor M1 is connected to the flip-flop SMIT and the control terminal of the first transistor M1. When there are n first transistors M1, where n is a positive integer greater than 1, the n first transistors M1 are connected in series, and the second terminal of each first transistor M1 is connected to its corresponding control terminal. The second terminal of the (n-1)th first transistor M1 is also connected to the first terminal of the nth first transistor M1. The first terminal of the first first transistor M1 is connected to the power supply VCC, and the second terminal of the nth first transistor M1 is connected to the flip-flop SMIT.

[0093] The input of flip-flop SMIT is used to receive communication signals. The output of flip-flop SMIT is connected to the input of inverter INV. The second power supply terminal of flip-flop SMIT is grounded. The output of inverter INV is used to output a second-level signal. The first power supply terminal of inverter INV is connected to the power supply, and the second power supply terminal of inverter INV is grounded.

[0094] The functional descriptions of the power supply VCC, the first transistor M1, the flip-flop SMIT, and the inverter INV in this embodiment can be found in the previous embodiments and will not be repeated here.

[0095] In one embodiment, such as Figure 10 As shown, this application also provides a communication interface circuit, which includes a power supply VCC, at least one diode D1, a flip-flop SMIT, and an inverter INV.

[0096] In the case of one diode D1, the anode of diode D1 is connected to the power supply VCC, and the cathode of diode D1 is connected to the flip-flop SMIT. In the case of m diodes D1, where m is a positive integer greater than 1, the m diodes D1 are connected in series, with the anode of the first diode D1 connected to the power supply VCC, and the cathode of the m-th diode D1 connected to the flip-flop SMIT.

[0097] The input of flip-flop SMIT is used to receive communication signals. The output of flip-flop SMIT is connected to the input of inverter INV. The second power supply terminal of flip-flop SMIT is grounded. The output of inverter INV is used to output a second-level signal. The first power supply terminal of inverter INV is connected to the power supply, and the second power supply terminal of inverter INV is grounded.

[0098] The functional descriptions of the power supply VCC, diode D1, trigger SMIT, and inverter INV in this embodiment can be found in the aforementioned embodiments and will not be repeated here.

[0099] In one embodiment, this application also provides a communication interface circuit, which can be referred to Figure 6It includes a power supply VCC, at least one first transistor M1, a second transistor M2, a third transistor M3, a fourth transistor M4, a capacitor C1, and an inverter INV1.

[0100] When there is only one first transistor M1, its first terminal is connected to the power supply VCC, and its second terminal is connected to the control terminal of the first transistor M1, the first terminal of the second transistor M2, the second terminal of the fourth transistor M4, and the first terminal of the capacitor C1. When there are n first transistors M1, they are connected in series, where n is a positive integer greater than 1. The control terminal of each first transistor M1 is connected to its corresponding second terminal. The second terminal of the (n-1)th first transistor M1 is also connected to the first terminal of the nth transistor. The first terminal of the first first transistor M1 is connected to the power supply VCC, and the second terminal of the nth first transistor M1 is also connected to the first terminals of the second transistor M2, the fourth transistor M4, and the first terminal of the capacitor C1.

[0101] The second terminal of the second transistor M2 is connected to the first terminal of the third transistor M3 and the input terminal of the inverter INV1, respectively. The control terminal of the second transistor M2 is connected to the control terminal of the third transistor M3. The second terminal of the third transistor M3 is grounded.

[0102] The first terminal of the fourth transistor M4 is connected to the power supply VCC, and the control terminal of the fourth transistor M4 is connected to the output terminal of the inverter INV1.

[0103] The first power supply terminal of inverter INV1 is connected to power supply VCC, and the second power supply terminal of inverter INV1 is grounded.

[0104] In one embodiment, this application also provides a communication interface circuit, which can be referred to Figure 7 It includes a power supply VCC, at least one diode D1, a second transistor M2, a third transistor M3, a fourth transistor M4, a capacitor C1, and an inverter INV1.

[0105] When there is only one diode D1, the anode of diode D1 is connected to the power supply VCC, and the cathode of diode D1 is connected to the first terminal of the second transistor M2, the second terminal of the fourth transistor M4, and the first terminal of capacitor C1. When there are m diodes D1, the m diodes D1 are connected in series, where m is a positive integer greater than 1. The anode of the first diode D1 is connected to the power supply VCC, and the cathode of the nth diode D1 is connected to the first terminal of the second transistor M2, the second terminal of the fourth transistor M4, and the first terminal of capacitor C1.

[0106] The second terminal of the second transistor M2 is connected to the first terminal of the third transistor M3 and the input terminal of the inverter INV1, respectively. The control terminal of the second transistor M2 is connected to the control terminal of the third transistor M3. The second terminal of the third transistor M3 is grounded.

[0107] The first terminal of the fourth transistor M4 is connected to the power supply VCC, and the control terminal of the fourth transistor M4 is connected to the output terminal of the inverter INV1.

[0108] The first power supply terminal of inverter INV1 is connected to power supply VCC, and the second power supply terminal of inverter INV1 is grounded.

[0109] In one embodiment, this application also provides a chip that may include the communication interface circuit provided in any of the above embodiments.

[0110] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0111] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0112] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A communication interface circuit, characterized in that, include: A power supply is used to provide power voltage. A voltage drop module, connected to the power supply, is used to step down the power supply voltage to output a supply voltage; A trigger module, connected to the voltage drop module and a reference ground, is used to receive communication signals and to output a first-level signal based on the communication signals under the influence of the power supply voltage and the ground voltage provided by the reference ground; wherein the first-level signal includes the power supply voltage or the ground voltage; the difference between the power supply voltage and the high-level lower limit of the communication signal is less than the sum of the voltage drop value and a preset value; wherein the voltage drop value is the difference between the power supply voltage and the power supply voltage, and the preset value is related to the trigger module; A level conversion module is connected to the trigger module and the power supply respectively, and is used to convert the first level signal into a second level signal under the action of the power supply voltage; wherein the voltage range of the second level signal is different from that of the communication signal.

2. The communication interface circuit according to claim 1, characterized in that, The voltage drop module includes at least one diode; When there is only one diode, the anode of the diode is connected to the power supply, and the cathode of the diode is connected to the trigger module. When the number of diodes is m, where m is a positive integer greater than 1, the m diodes are connected in series, wherein the anode of the first diode is connected to the power supply, and the cathode of the mth diode is connected to the trigger module; The diode is used to step down the power supply voltage to output the supply voltage.

3. The communication interface circuit according to claim 1, characterized in that, The voltage drop module includes at least one first transistor; When the number of the first transistor is one, the first terminal of the first transistor is connected to the power supply, and the second terminal of the first transistor is connected to the trigger module and the control terminal of the first transistor. When the number of the first transistors is n, where n is a positive integer greater than 1, the n first transistors are connected in series, and the second terminal of each first transistor is connected to the control terminal. The second terminal of the (n-1)th first transistor is also connected to the first terminal of the nth first transistor. The first terminal of the first first transistor is connected to the power supply, and the second terminal of the nth first transistor is connected to the trigger module. The first transistor is used to step down the power supply voltage to output the power supply voltage.

4. The communication interface circuit according to claim 1, characterized in that, The triggering module includes: The second transistor has a first terminal connected to the voltage drop module and a second terminal connected to the level conversion module. The control terminal of the second transistor is used to receive the communication signal. The third transistor has its first terminal connected to the level conversion module and the second terminal of the second transistor, and its second terminal connected to the reference ground. The control terminal of the third transistor is used to receive the communication signal. The common connection terminal of the second transistor and the third transistor is also used to output the first level signal, which is opposite in phase to the communication signal.

5. The communication interface circuit according to claim 4, characterized in that, The preset value is the conduction threshold of the second transistor.

6. The communication interface circuit according to claim 1, characterized in that, The triggering module includes: The comparator is connected to the voltage drop module, the reference ground, and the level conversion module respectively, and is used to output the first level signal according to the communication signal under the action of the supply voltage and the ground voltage; the set threshold of the comparator is less than the supply voltage.

7. The communication interface circuit according to claim 6, characterized in that, The preset value is zero.

8. The communication interface circuit according to claim 1, characterized in that, The level conversion module includes: An inverter, connected to the power supply, the trigger module, and the reference ground respectively, is used to invert the first level signal under the action of the power supply voltage and output a second level signal, wherein the set threshold of the inverter is less than the power supply voltage.

9. The communication interface circuit according to claim 1, characterized in that, The communication interface circuit also includes: The feedback pull-up module has its input terminal connected to the level conversion module, its output terminal connected to the voltage drop module and the trigger module, its first power supply terminal connected to the power supply, and its second power supply terminal grounded. The feedback pull-up module is used to output the power supply voltage to the trigger module when the second level signal is a first voltage value.

10. The communication interface circuit according to claim 9, characterized in that, The feedback pull-up module includes: The fourth transistor has its control terminal connected to the level conversion module, its first terminal connected to the power supply, and its second terminal connected to the voltage drop module and the trigger module, respectively. A capacitor, the first terminal of which is connected to the second terminal of the fourth transistor, and the second terminal of which is grounded.

11. A communication interface circuit, characterized in that, include: A power supply, at least one first transistor, a flip-flop, and an inverter; Wherein, when there is only one first transistor, the first terminal of the first transistor is connected to the power supply, and the second terminal of the first transistor is connected to the flip-flop and the control terminal of the first transistor; when there are n first transistors, where n is a positive integer greater than 1, the n first transistors are connected in series, and the second terminal of each first transistor is connected to the corresponding control terminal, the second terminal of the (n-1)th first transistor is also connected to the first terminal of the nth first transistor, the first terminal of the first first transistor is connected to the power supply, and the second terminal of the nth first transistor is connected to the flip-flop; The input terminal of the flip-flop is used to receive communication signals, the output terminal of the flip-flop is connected to the input terminal of the inverter, and the second power supply terminal of the flip-flop is grounded. The output terminal of the inverter is used to output a second level signal. The first power supply terminal of the inverter is connected to the power supply, and the second power supply terminal of the inverter is grounded.

12. A communication interface circuit, characterized in that, include: Power supply, at least one diode, flip-flop, and inverter; Where the number of diodes is one, the anode of the diode is connected to the power supply, and the cathode of the diode is connected to the trigger; where the number of diodes is m, where m is a positive integer greater than 1, the m diodes are connected in series, wherein the anode of the first diode is connected to the power supply, and the cathode of the mth diode is connected to the trigger. The input terminal of the flip-flop is used to receive communication signals, the output terminal of the flip-flop is connected to the input terminal of the inverter, and the second power supply terminal of the flip-flop is grounded. The output terminal of the inverter is used to output a second level signal. The first power supply terminal of the inverter is connected to the power supply, and the second power supply terminal of the inverter is grounded.

13. A communication interface circuit, characterized in that, include: A power supply, at least one first transistor, a second transistor, a third transistor, a fourth transistor, a capacitor, and an inverter; When there is only one first transistor, the first terminal of the first transistor is connected to the power supply, and the second terminal of the first transistor is connected to the control terminal of the first transistor, the first terminal of the second transistor, the second terminal of the fourth transistor, and the first terminal of the capacitor. When there are n first transistors, the n first transistors are connected in series, where n is a positive integer greater than 1. The control terminal of each first transistor is connected to its corresponding second terminal, the second terminal of the (n-1)th first transistor is also connected to the first terminal of the nth transistor, the first terminal of the first first transistor is connected to the power supply, and the second terminal of the nth first transistor is also connected to the first terminal of the second transistor, the second terminal of the fourth transistor, and the first terminal of the capacitor. The second terminal of the second transistor is connected to the first terminal of the third transistor and the input terminal of the inverter, respectively; the control terminal of the second transistor is connected to the control terminal of the third transistor; the second terminal of the third transistor is grounded. The first terminal of the fourth transistor is connected to the power supply, and the control terminal of the fourth transistor is connected to the output terminal of the inverter. The first power supply terminal of the inverter is connected to the power supply, and the second power supply terminal of the inverter is grounded.

14. A communication interface circuit, characterized in that, include: A power supply, at least one diode, a second transistor, a third transistor, a fourth transistor, a capacitor, and an inverter; When there is one diode, the anode of the diode is connected to the power supply, and the cathode of the diode is connected to the first terminal of the second transistor, the second terminal of the fourth transistor, and the first terminal of the capacitor, respectively. When there are m diodes, the m diodes are connected in series, where m is a positive integer greater than 1. The anode of the first diode is connected to the power supply, and the cathode of the nth diode is connected to the first terminal of the second transistor, the second terminal of the fourth transistor, and the first terminal of the capacitor. The second terminal of the second transistor is connected to the first terminal of the third transistor and the input terminal of the inverter, respectively; the control terminal of the second transistor is connected to the control terminal of the third transistor; the second terminal of the third transistor is grounded. The first terminal of the fourth transistor is connected to the power supply, and the control terminal of the fourth transistor is connected to the output terminal of the inverter. The first power supply terminal of the inverter is connected to the power supply, and the second power supply terminal of the inverter is grounded.

15. A chip, characterized in that, Includes the communication interface circuit as described in any one of claims 1-14.

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