Novel high-precision current-to-current isolation circuit
By designing a high-precision current-to-current isolation circuit including precision potentiometer and transformer isolation circuit, the problems of signal distortion, instability and low accuracy in the prior art are solved, and the current isolation effect of high-precision, low distortion and anti-interference are achieved.
Patent Information
- Application Number
- CN202421889880.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-06
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-08-06
AI Technical Summary
The existing current-to-current isolation technology has problems such as signal distortion, unstable output signal, low accuracy and serious signal loss in industrial environments.
A high-precision current-to-current isolation circuit including a precision potentiometer input regulation circuit, a transformer isolation circuit, a precision potentiometer output regulation circuit and an amplification filter circuit are designed. This circuit realizes precise control and isolation of signals through precision potentiometers and transformer isolation circuits, while the amplification filter circuit is used to enhance signals and filter interference.
It realizes high-precision, low distortion and strong anti-interference ability to current-to-current isolation, ensuring the stability and reliability of signal transmission.
Smart Images
Figure CN222954014U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of circuit application, in particular to a novel high-precision current-to-current isolation circuit. Background Art
[0002] In modern electronic devices, current-to-current isolation technology is a commonly used electronic circuit design technology, which is used to convert the current signal at the input end into the current signal at the output end and simultaneously achieve electrical isolation between the input and output ends.
[0003] In some specific application scenarios, it is necessary to transmit current signals from one circuit to another, but it is necessary to maintain electrical isolation between the input and output terminals to avoid potential electrical interference and safety risks. Current-to-current isolation technology can effectively ensure the stability and reliability of signal transmission.
[0004] In the existing industrial environment, with the development of industry, although current-to-current isolation technology has wide application and importance in electronic circuit design, it also has some technical deficiencies and shortcomings: 1) signal distortion and unstable output signal; 2) low accuracy and serious signal loss; 3) high cost and other issues. Utility Model Content
[0005] In order to solve the above problems, the utility model provides a novel high-precision current-to-current isolation circuit, including a precision potentiometer input adjustment circuit, a transformer isolation circuit, a precision potentiometer output adjustment circuit, and an amplifying and filtering circuit; the precision potentiometer input adjustment circuit is used to receive external current and voltage and transmit them to the transformer isolation circuit; the transformer isolation circuit is used to generate a common signal and an alternating signal and transmit them to the amplifying and filtering circuit; the precision potentiometer output adjustment circuit is used to convert the alternating signal into a fixed DC signal and then transmit it to the amplifying and filtering circuit; the amplifying and filtering circuit is used to amplify the fixed DC signal to the same as the external input current and voltage and then output it.
[0006] Furthermore, the precision potentiometer input adjustment circuit specifically includes: a precision potentiometer R1, a capacitor C1, a capacitor C2, a capacitor C3, a diode D1, and a resistor R2;
[0007] The A end of the precision potentiometer R1 is connected to the current positive voltage, and the B end is grounded; the diode D1 is connected in series with the capacitor C2 and then connected in parallel with the A end and the C end of the precision potentiometer R1; the capacitor C1, the capacitor C2, and the resistor R2 are connected in series and then connected in parallel with the capacitor C3.
[0008] Furthermore, the transformer isolation circuit specifically includes: a micro transformer driver U1, a transformer T1, a transformer T2, a switch diode D2, a switch diode D3, a MOS tube Q1, a MOS tube Q2, a capacitor C4, a capacitor C5, a capacitor C6, a resistor R3, a resistor R4, a resistor R5, and a resistor R6;
[0009] The switching diodes D2 and D3 are connected in series to the transformer T1 after receiving the current and voltage signals. One end of the micro-transformer driver U1 is connected in series to the transformer T1, and the other end is grounded. The C end of the switching diode D2 is connected in series with the capacitor C4, the resistor R3, the resistor R4, and the capacitor C6 in sequence, and the resistor R4 is connected in parallel with the A end and the C end of the MOS tube Q1. The C end of the switching diode D3 is connected in series with the capacitor C5, the resistor R5, and the resistor R6 in sequence, and the resistor R6 is connected in parallel with the A end and the C end of the MOS tube Q2.
[0010] Furthermore, the precision potentiometer output adjustment circuit specifically includes: a resistor R12, a precision potentiometer R13, and a resistor R14; the resistor R14, the precision potentiometer R13, and the resistor R12 are connected in series in sequence.
[0011] Furthermore, the amplifying and filtering circuit specifically includes: a switching diode D4, a capacitor C9, a capacitor C10, a capacitor C11, a capacitor C12, a capacitor C13, a capacitor C14, a capacitor C15, a capacitor C16, a capacitor C17, a MOS tube Q5, an operational amplifier U2, a resistor R15, a resistor R16, a resistor R17, a resistor R18, and a resistor R19.
[0012] Furthermore, an output circuit is also included, and the output circuit specifically includes: a switching diode D5, a switching diode D6, a capacitor C7, a capacitor C8, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a MOS tube Q3, and a MOS tube Q4;
[0013] After receiving the current and voltage signals, the switching diode D5 is connected in series with the capacitor C7, the resistor R8, and the MOS tube Q3 in sequence; the resistor R9 is connected in parallel with the A end and the C end of the MOS tube Q3; after receiving the current and voltage signals, the switching diode D6 is connected in series with the capacitor C8, the resistor R10, and the MOS tube Q4 in sequence; the resistor R11 is connected in parallel with the A end and the C end of the MOS tube Q4.
[0014] Furthermore, it also includes an RC filter circuit; the RC filter circuit is composed of a resistor and a capacitor, and is used to filter high-frequency interference that occurs during signal transmission.
[0015] The utility model provides a novel high-precision current-to-current isolation circuit, which has the following beneficial effects:
[0016] The utility model has the characteristics of high precision, low distortion and strong anti-interference ability, mainly because of its precise control of the front and rear end currents, which can suppress high-frequency interference in the environment. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.
[0018] Figure 1 This is a schematic diagram of the structure of the precision potentiometer input adjustment circuit provided by the utility model;
[0019] Figure 2 A schematic diagram of the transformer isolation circuit structure provided by the utility model;
[0020] Figure 3 A schematic diagram of the output circuit structure provided by the utility model;
[0021] Figure 4 This is a schematic diagram of the structure of the precision potentiometer output adjustment circuit and the amplification and filtering circuit provided by the utility model. DETAILED DESCRIPTION
[0022] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.
[0023] The following is a detailed description of the implementation method of the present invention in conjunction with the accompanying drawings. Only some embodiments are described, not all embodiments. For the purpose of clarity, representations and descriptions that are not related to the present invention are omitted in the drawings and descriptions.
[0024] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the utility model, the technical solution of the utility model is now described in detail below. Obviously, the implementation cases described are part of the embodiments of the utility model, not all of the embodiments, and cannot be understood as limiting the scope of implementation of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the utility model.
[0025] The utility model provides a novel high-precision current-to-current isolation circuit, comprising a precision potentiometer input adjustment circuit, a transformer isolation circuit, a precision potentiometer output adjustment circuit, and an amplifying and filtering circuit; the precision potentiometer input adjustment circuit is used for receiving external current and voltage and transmitting them to the transformer isolation circuit; the transformer isolation circuit is used for generating a common signal and an alternating signal and transmitting them to the amplifying and filtering circuit; the precision potentiometer output adjustment circuit is used for converting the alternating signal into a fixed DC signal and then transmitting it to the amplifying and filtering circuit; the amplifying and filtering circuit is used for amplifying the fixed DC signal to be the same as the external input current and voltage and then outputting it.
[0026] Precision potentiometer input adjustment circuit, such as Figure 1 As shown, it specifically includes: a precision potentiometer R1, a capacitor C1, a capacitor C2, a capacitor C3, a diode D1, and a resistor R2; the A end of the precision potentiometer R1 is connected to a current positive voltage, and the B end is grounded; the diode D1 is connected in series with the capacitor C2 and then connected in parallel with the A end and the C end of the precision potentiometer R1; the capacitor C1, the capacitor C2, and the resistor R2 are connected in series and then connected in parallel with the capacitor C3.
[0027] input+ is the positive input signal; input- is the negative input signal; R1 is a precision potentiometer; by adjusting the precision potentiometer R1, the current between the input end and one end of the input transformer is controlled. Figure 2 , Figure 3 output1+ is used for micro-processing of subsequent current precise control.
[0028] The transformer isolation circuit specifically includes, for example Figure 2 As shown: micro transformer driver U1, transformer T1, transformer T2, switching diode D2, switching diode D3, MOS tube Q1, MOS tube Q2, capacitor C4, capacitor C5, capacitor C6, resistor R3, resistor R4, resistor R5, resistor R6.
[0029] After receiving the current and voltage signals, the switching diodes D2 and D3 are connected in series to the transformer T1. One end of the micro-transformer driver U1 is connected in series to the transformer T1, and the other end is grounded. The C end of the switching diode D2 is connected in series with the capacitor C4, the resistor R3, the resistor R4, and the capacitor C6 in sequence, and the resistor R4 is connected in parallel with the A end and the C end of the MOS tube Q1. The C end of the switching diode D3 is connected in series with the capacitor C5, the resistor R5, and the resistor R6 in sequence, and the resistor R6 is connected in parallel with the A end and the C end of the MOS tube Q2.
[0030] The transformer driver U1 drives the transformer T1 to work, and the 4 and 5 pins of the transformer T1 generate alternating signals. The 5 and 6 pins at the other end of the transformer T1 simultaneously generate alternating signals, and the 5 and 6 pins are connected to the switching diodes D2 and D3. Due to the existence of the switching diodes D2 and D3, the alternating signal generated by the transformer T1 will not affect the output signal of the output1+ previous level.
[0031] At the same time, the alternating signal generated by the 5th and 6th pins of the transformer T1 filters the DC signal in the circuit through the capacitors C4 and C5, and the resistors R3 and R5 limit the current, and connect the gates of the MOS tubes Q1 and Q2. The switches of the MOS tubes Q1 and Q2 are alternately controlled by the alternating signal, so that the alternating signal generated at both ends of the connected transformer T2 causes the other end of the transformer T2 to generate the common signal SigO and the alternating signals SigP and SigN.
[0032] like Figure 4 As shown, the precision potentiometer output adjustment circuit specifically includes: a resistor R12, a precision potentiometer R13, and a resistor R14; the resistor R14, the precision potentiometer R13, and the resistor R12 are connected in series in sequence.
[0033] The amplifying and filtering circuit specifically includes: a switching diode D4, a capacitor C9, a capacitor C10, a capacitor C11, a capacitor C12, a capacitor C13, a capacitor C14, a capacitor C15, a capacitor C16, a capacitor C17, a MOS tube Q5, an operational amplifier U2, a resistor R15, a resistor R16, a resistor R17, a resistor R18, and a resistor R19.
[0034] Also includes output circuits, such as Figure 3 As shown, the output circuit specifically includes: a switching diode D5, a switching diode D6, a capacitor C7, a capacitor C8, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a MOS tube Q3, and a MOS tube Q4.
[0035] After receiving the current and voltage signals, the switching diode D5 is connected in series with the capacitor C7, the resistor R8, and the MOS tube Q3 in sequence; the resistor R9 is connected in parallel with the A end and the C end of the MOS tube Q3; after receiving the current and voltage signals, the switching diode D6 is connected in series with the capacitor C8, the resistor R10, and the MOS tube Q4 in sequence; the resistor R11 is connected in parallel with the A end and the C end of the MOS tube Q4.
[0036] It also includes an RC filter circuit; the RC filter circuit is composed of a resistor and a capacitor and is used to filter high-frequency interference that occurs during signal transmission.
[0037] The alternating signals OutputP and OutputN generated by transformer T1 control MOS transistors Q6 and Q7 to switch regularly so that their signals SigP and SigN form alternating signals. Therefore, the SigO terminal of transformer T2 can work normally.
[0038] The alternating signals OutputP and OutputN are rectified into fixed DC signals through the switching diodes D5 and D6, and then output to the final output terminal through the second-stage output output2+. Because the output2+ output signal is a fixed value, there will be a certain loss in the signal transmission process, resulting in an increase in the distortion rate. Therefore, the signal needs to be compensated.
[0039] The common terminal signal SigO is generated by the above transformer isolation circuit. The signal passes through the signal amplification circuit composed of resistors R15, R17, R19, and operational amplifier U2. The alternating signal generated by the transformer isolation circuit is amplified to the same voltage as the input terminal. By adjusting the precision potentiometer R13, and because of Ohm's law U=IR, the voltage remains unchanged, and the current is inversely proportional to the resistance.
[0040] Therefore, the current at the output end is precisely calibrated by the precision potentiometer R13 to make the current at the output end equal to the current at the input end. The MOS tube Q5 controls the continuous switching of the MOS tube Q5 through the amplified alternating signal output by the operational amplifier U2, and generates an adjusted alternating signal at the drain of the MOS tube Q5. The alternating signal is compensated to the positive output terminal of output2+ through the capacitor C12. Due to the characteristics of capacitor C12 that blocks DC and passes AC, after the AC signal is compensated to the DC signal of output2+, the DC signal output2+ is prevented from flowing back and causing signal attenuation.
[0041] The utility model has the characteristics of high precision, low distortion and strong anti-interference ability, mainly because of its precise control of the front and rear end currents, which can suppress high-frequency interference in the environment.
[0042] The above is only a preferred embodiment of the utility model. It should be understood that the utility model is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the utility model, and should be within the scope of protection of the claims attached to the utility model.
Claims
1. A new type of high-precision current-to-current isolation circuit, characterized in that: It includes a precision potentiometer input adjustment circuit, a transformer isolation circuit, a precision potentiometer output adjustment circuit, and an amplification and filtering circuit; The precision potentiometer input adjustment circuit is used to receive external current and voltage and transmit them to the transformer isolation circuit; The transformer isolation circuit is used to generate a common signal and an alternating signal to be transmitted to the amplification and filtering circuit; The precision potentiometer output adjustment circuit is used to convert the alternating signal into a fixed DC signal and then transmit it to the amplification and filtering circuit; The amplifying and filtering circuit is used to amplify the fixed DC signal to the same voltage as the external input current and then output it.
2. The novel high-precision current-to-current isolation circuit according to claim 1 is characterized in that: The precision potentiometer input adjustment circuit specifically includes: a precision potentiometer R1, a capacitor C1, a capacitor C2, a capacitor C3, a diode D1, and a resistor R2; The A end of the precision potentiometer R1 is connected to the current positive voltage, and the B end is grounded; the diode D1 is connected in series with the capacitor C2 and then connected in parallel with the A end and the C end of the precision potentiometer R1; the capacitor C1, the capacitor C2, and the resistor R2 are connected in series and then connected in parallel with the capacitor C3.
3. The novel high-precision current-to-current isolation circuit according to claim 1 is characterized in that: The transformer isolation circuit specifically includes: a micro transformer driver U1, a transformer T1, a transformer T2, a switch diode D2, a switch diode D3, a MOS tube Q1, a MOS tube Q2, a capacitor C4, a capacitor C5, a capacitor C6, a resistor R3, a resistor R4, a resistor R5, and a resistor R6; The switching diodes D2 and D3 are connected in series to the transformer T1 after receiving the current and voltage signals. One end of the micro-transformer driver U1 is connected in series to the transformer T1, and the other end is grounded. The C end of the switching diode D2 is connected in series with the capacitor C4, the resistor R3, the resistor R4, and the capacitor C6 in sequence, and the resistor R4 is connected in parallel with the A end and the C end of the MOS tube Q1. The C end of the switching diode D3 is connected in series with the capacitor C5, the resistor R5, and the resistor R6 in sequence, and the resistor R6 is connected in parallel with the A end and the C end of the MOS tube Q2.
4. The novel high-precision current-to-current isolation circuit according to claim 1 is characterized in that: The precision potentiometer output adjustment circuit specifically includes: a resistor R12, a precision potentiometer R13, and a resistor R14; the resistor R14, the precision potentiometer R13, and the resistor R12 are connected in series in sequence.
5. The novel high-precision current-to-current isolation circuit according to claim 1 is characterized in that: The amplifying and filtering circuit specifically includes: a switching diode D4, a capacitor C9, a capacitor C10, a capacitor C11, a capacitor C12, a capacitor C13, a capacitor C14, a capacitor C15, a capacitor C16, a capacitor C17, a MOS tube Q5, an operational amplifier U2, a resistor R15, a resistor R16, a resistor R17, a resistor R18, and a resistor R19.
6. The novel high-precision current-to-current isolation circuit according to claim 1 is characterized in that: It also includes an output circuit, which specifically includes: a switching diode D5, a switching diode D6, a capacitor C7, a capacitor C8, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a MOS tube Q3, and a MOS tube Q4; After receiving the current and voltage signals, the switching diode D5 is connected in series with the capacitor C7, the resistor R8, and the MOS tube Q3 in sequence; the resistor R9 is connected in parallel with the A end and the C end of the MOS tube Q3; after receiving the current and voltage signals, the switching diode D6 is connected in series with the capacitor C8, the resistor R10, and the MOS tube Q4 in sequence; the resistor R11 is connected in parallel with the A end and the C end of the MOS tube Q4.
7. The novel high-precision current-to-current isolation circuit according to claim 1 is characterized in that: It also includes an RC filter circuit; The RC filter circuit is composed of a resistor and a capacitor and is used to filter high-frequency interference that occurs during signal transmission.