Double-energy-storage-unit noise suppression circuit based on time-sharing control and dynamic isolation

Abstract

The invention discloses a double energy storage unit noise suppression circuit based on time-sharing control and dynamic isolation, and belongs to the technical field of power supply noise suppression. The circuit comprises a pre-charging and starting module, an energy storage module, a time-sharing control and isolation module, a transient suppression module, a triggering and state keeping module, a voltage detection module and a CLC filter network. The energy storage module comprises two energy storage units with the same specification; the time-sharing control and isolation module adopts a mechanical or electrical linkage double-SPDT switch structure, and blocks an external noise conduction path through a physical isolation mode; and the triggering and state maintaining module adopts a rising edge to trigger a D trigger to control the two energy storage units to charge and discharge alternately. Through time-sharing control and a dynamic isolation mechanism, under the conditions of the environment temperature of 25 DEG C + / -2 DEG C and the bandwidth of 100 kHz, the output noise voltage is 0.5-5 [mu] Vrms, the power supply ripple suppression ratio reaches 110-140 dB, and the power supply noise suppression problem of high-precision electronic equipment is effectively solved.

Description

Technical Field

[0001] This invention relates to power supply noise suppression circuits, particularly a noise suppression circuit based on dual energy storage units and time-division switching isolation, belonging to the field of power supply technology. Specifically, it relates to a power supply circuit that, under ambient temperature conditions of 25℃±2℃ and a bandwidth of 100kHz (according to IEC 61967-4 standard), achieves a measured output noise voltage of 0.5μV rms~5μV rms (RMS) and a power supply ripple rejection ratio (PSRR) of 110dB~140dB (input ripple frequency 100Hz to 1MHz, amplitude 100mVpp). Under the same test conditions, this invention improves the PSRR by more than 40dB compared to traditional LDO solutions. The load driving capability of this invention depends on the capacity of the energy storage units. Background Technology

[0002] Conducted noise in existing power supply circuits can affect the performance of precision equipment. Power supply noise can reduce the signal-to-noise ratio of precision equipment. In existing technologies, the PSRR of LDO power supplies is usually below 80dB.

[0003] Existing power supply circuits have the following shortcomings in noise suppression:

[0004] 1. The PSRR of the LDO power supply is less than 80dB;

[0005] 2. The PSRR of the switching power supply drops by more than 15dB in the 1MHz band;

[0006] 3. Changes in the output capacitor's ESR can cause a 40% decrease in loop stability.

[0007] Electronic noise has evolved from a traditional interference factor into a fundamental physical limit restricting technological development, necessitating the reconstruction of noise suppression modes.

[0008] Existing technology

[0009] Currently, the noise floor of conventional oscilloscopes has reached 50μV rms or even higher, while the reference value of quantum noise at 25℃ is about 0.4μV rms / √Hz. This means that achieving a noise voltage below 5μV rms and a power supply ripple suppression capability of 100PSRR is a current technical challenge. Existing semiconductor junction temperatures exceeding 85℃ will cause PSRR to degrade by 20dB. If the design value is 80dB, removing 20dB may cause the device to fail. Without sufficient design margin, the safe and accurate operation of the device is limited. However, at an ambient temperature of 85℃, the PSRR of this invention still remains ≥100dB.

[0010] Achieving ultra-low noise output below 10μV rms and a PSRR exceeding 100dB is a core challenge in precision power supply design, posing a significant hurdle in high-precision instruments, advanced medical equipment, high-sensitivity RF systems, GPS receivers, and military equipment. High-frequency PSRR optimization is crucial; ordinary LDOs experience a PSRR drop of over 15dB at 1MHz, and even top-tier LDOs can only maintain a PSRR of 70–80dB at 100kHz.

[0011] Meanwhile, when the ESR of the output capacitor increases from 5mΩ to 80mΩ, the loop stability decreases by 40%, necessitating the selection of a combination of X7R / X7S material with a capacitance greater than 22μF. At a switching frequency of 500kHz, using a π-type filter (ferrite bead + 10μF ceramic capacitor) can improve the PSRR by 8dB.

[0012] The core challenges of current noise suppression:

[0013] The physical limits of material-level noise: 1 / f noise is strongly correlated with lattice defects. Although new semiconductor materials (such as GaN) can reduce white noise, dislocation defects still cause 1 / f noise to be 30% higher than that of silicon-based devices, and the cost of material modification increases sharply. Design conflicts under nanoscale processes; power integrity dilemma: to reduce IR voltage drop, power lines need to be widened, but the increase in linewidth leads to an increase in parasitic inductance. In 3nm processes, L·di / dt noise contributes up to 60% of the total noise. Decoupling capacitor failure: on-chip nanocapacitor density is limited (<300nF / mm²). 2 However, it cannot effectively suppress current ripple above 10 GHz. Multi-physics noise coupling occurs in motor systems. Electromagnetic noise suppression requires reducing air gap magnetic field harmonics, but this leads to increased torque fluctuations and mechanical vibrations, forming an acoustic-magnetic-thermal positive feedback loop.

[0014] High-frequency noise suppression is a bottleneck. EMI suppression of switching power supplies above 10MHz requires magnetic common-mode chokes, but the permeability of nanocrystalline materials decreases by 50% at high temperatures, causing a sharp drop in filtering efficiency. Radiated noise shielding requires a metal-sealed cavity, but this hinders heat dissipation; for every 1mm increase in aluminum plate thickness, the chip junction temperature rises by 8℃.

[0015] Novel topologies and novel devices have become key approaches to solving noise problems.

[0016] Purpose of the invention

[0017] The main objective of this invention is to eliminate classical electronic noise interference in power supply circuits, excluding unavoidable noise such as thermal noise and quantum noise, thereby achieving higher PSRR noise suppression capability and lower noise voltage within a bandwidth of 10Hz to 100kHz: 1. Limiting noise to the range of 0.5uVrms to 5uVrms. 2. Achieving a power supply ripple rejection ratio (PSRR) of 110dB to 140dB.

[0018] In actual measurements, the maximum PSRR reached 120dB within a bandwidth of 25℃±2℃ and 10Hz~100kHz, and a ripple suppression capability of 140dB was achieved when using a relay.

[0019] Advantages of the invention

[0020] 1. Isolate useful radio frequency signals in the circuit, blocking their leakage through the power supply.

[0021] 2. To minimize the interference of external noise on the circuit, thereby improving the circuit's signal-to-noise ratio by more than 40dB.

[0022] 3. In medical imaging systems, improving the system's signal-to-noise ratio (SNR) enhances image quality, increases image resolution, and improves diagnostic accuracy.

[0023] 4. In terms of high-precision testing and measurement, it is widely used in fields such as semiconductor testing, integrated circuit verification, and sensor calibration to ensure the accuracy of performance evaluation and measurement precision.

[0024] 5. Improve sound purity in audio preamplifiers.

[0025] 6. In radio frequency applications, it can improve the signal-to-noise ratio, prevent signal distortion, reduce bit error rate, reduce radio frequency interference, improve communication quality, increase data transmission rate, improve frequency stability, improve radio frequency circuit stability, and improve signal coverage quality.

[0026] 7. Prevent logic errors or timing disorders in high-frequency digital circuits.

[0027] 8. Suitable for electronic devices that require extremely low noise. Summary of the Invention

[0028] This invention provides a power supply system with dual energy storage units that can be charged and discharged in a time-sharing manner. The system controls two identical energy storage units via a linkage switch. While one unit supplies power to the load, the other unit can charge or standby, thus achieving continuous power supply and limiting noise to 0.5uVrms to 5uVrms within a 10Hz to 100kHz bandwidth. Furthermore, it achieves a power supply ripple rejection ratio (PSRR) of 110dB to 140dB.

[0029] This invention comprises a pre-charging and startup module (1), an energy storage module (2), a time-sharing control and isolation module (3), a transient suppression module (4), a triggering and state holding module (5), a voltage detection module (6), and a CLC filter network (7). The energy storage module includes a first energy storage unit (EC1) and a second energy storage unit (EC2), which are identical in specifications. The time-sharing control and isolation module includes a first switching switch (SPDT1) and a second switching switch (SPDT2) with mechanical or electrical linkage, both of which are SPDT switches.

[0030] The following are the connection relationships:

[0031] The positive terminal of the first energy storage unit of the energy storage module is connected to the pre-charging and start-up module, and is also connected to the common terminal of the first switching switch of the time-sharing control and isolation module; the positive terminal of the second energy storage unit is connected to the common terminal of the second switching switch, and the negative terminals of both the first and second energy storage units are grounded.

[0032] The common terminal of the first switching switch of the time-sharing control and isolation module is connected to the positive terminal of the first energy storage unit and is also connected to the pre-charging and start-up module; the common terminal of the second switching switch is connected to the positive terminal of the second energy storage unit; the first switching switch and the second switching switch are linked, that is, the control terminals of the first switching switch and the second switching switch are connected together and connected to the output terminal of the triggering and state holding module and are controlled by the triggering and state holding module; the normally closed NC terminal of the first switching switch is connected to the normally open NO terminal of the second switching switch and is connected to the external power supply input; after the normally open NO terminal of the first switching switch and the normally closed NC terminal of the second switching switch are connected, they are connected to the input terminal of the transient suppression module.

[0033] The pre-charging and start-up module has its input terminal connected to the positive terminal of the first energy storage unit of the energy storage module to detect whether the first energy storage unit is fully charged, thereby determining whether the circuit can start and run; its output is divided into two paths. When the voltage of the first energy storage unit is fully charged, one path outputs power to the trigger and state holding module, and the other path outputs a signal to trigger the trigger and state holding module with a rising edge validity.

[0034] The voltage detection module has its input terminal connected to the output terminal of the transient suppression module and the input terminal of the CLC filter network, and its output terminal connected to the input terminal of the trigger and state holding module.

[0035] The triggering and state holding module has its input terminal connected to the output terminal of both the voltage detection module and the pre-charge and start-up module. Upon responding to their signals, it triggers the generation of an output signal. Since its output terminal is connected to the input terminal of the time-sharing control and isolation module, the switching action of the time-sharing control and isolation module is controlled by the voltage change at the output terminal.

[0036] The input terminal of the transient suppression module is connected to the output terminal of the time-sharing control and isolation module, that is, it is connected to the normally open NO terminal of the first switching switch and the normally closed NC terminal of the second switching switch. The output terminal is connected to the input terminal of the CLC filter network and the input terminal of the voltage detection module.

[0037] The CLC filter network has its input terminal connected to the output terminal of the transient suppression module and also connected to the input terminal of the voltage detection module, while its output terminal is connected to the load.

[0038] The innovative technical solution of this invention is as follows:

[0039] 1. Dual energy storage unit time-sharing charging and discharging architecture: Through the time-sharing alternating charging and discharging of the first energy storage unit (EC1) and the second energy storage unit (EC2), power supply continuity is achieved, while blocking external power noise from being directly coupled to the load.

[0040] 2. Noise isolation mechanism of SPDT switches: SPDT switches (SPDT1, SPDT2) with mechanical or electrical linkage are used to completely isolate the charging and discharging circuit during switching, avoiding ground noise interference (measured PSRR reaches 110dB~140dB).

[0041] 3. CLC filter network design: Use two or more CLC filter units. The front stage mainly filters out external power supply noise interference, and the rear stage mainly blocks useful signals from leaking from the power supply at the load end, as shown in the example (L1 / C1 / C2, L2 / C3 / C4) cascaded.

[0042] The function and principle of time-sharing technology:

[0043] The core of this invention is the use of time-sharing technology, which mainly achieves two core functions through time-sharing control and isolation modules: efficient isolation and intelligent energy scheduling.

[0044] I. Core Role

[0045] High-efficiency isolation and noise blocking

[0046] Mechanism: By using time-sharing control and linkage mechanical / electrical switches in the isolation module, the direct electrical connection between the external power supply network and the internal load circuit is physically and dynamically isolated.

[0047] Results: This approach fundamentally eliminates interference such as noise and voltage fluctuations introduced by external power supplies. Testing has shown that this design achieves a power supply rejection ratio (PSRR) of 110dB to 140dB, far exceeding the typical value (30dB to 80dB) of traditional linear regulators (LDOs), providing an extremely clean power supply to the load.

[0048] Intelligent energy time-sharing management

[0049] Mechanism: The charging and discharging processes of the two energy storage units are controlled in a time-sharing manner to ensure seamless energy transfer.

[0050] Effect:

[0051] Startup Management: During the initial power-up of the system, the energy storage unit is fully charged to the rated voltage before power is supplied to the load, ensuring that the load starts smoothly under the rated voltage.

[0052] Continuous power supply: During normal operation, the two energy storage units are controlled to alternately charge and discharge. When one unit is discharging under load, the other unit is connected to an external power source for charging, thereby achieving uninterrupted power supply.

[0053] II. Working Principle

[0054] The operation of the time-sharing control and isolation module involves two key states, the switching of which is controlled by signals output from the triggering and state-holding modules:

[0055] State 1: Initial pre-charging and startup: After the system is powered on, the external power supply charges the first energy storage unit (EC1) through the default path (SPDT1-NC, SPDT2-NO) of the time-sharing control and isolation module.

[0056] When the precharge and start-up module detects that the EC1 voltage has reached a preset value, its start-up circuit generates a trigger signal.

[0057] The trigger and state holding module responds to this signal by outputting a control level, which drives the linkage switch in the time-sharing control and isolation module to switch to the next state.

[0058] State 2: Alternating charge and discharge operation: After the interlock switch is activated, the following will occur:

[0059] Connect the discharge circuit: Connect the fully charged EC1 (through SPDT1-NO) to the transient suppression module and the load to start discharging.

[0060] Connect the charging circuit: Simultaneously, switch the external power supply (via SPDT2-NC) to charge the second energy storage unit (EC2). The voltage detection module continuously monitors the output voltage. When EC1 is about to run out of power, causing the output voltage to drop, the trigger and state holding module will be triggered to change the output again, controlling the linkage switch to switch back to a configuration similar to state one, but with roles reversed: EC2 will discharge while EC1 is charged.

[0061] This cycle repeats continuously, enabling automatic and alternating switching between the charging and discharging states of the two energy storage units, thus ensuring the continuity of power supply to the load.

[0062] Functions and collaboration principles of each module:

[0063] 1. Energy storage module

[0064] Function: To serve as a direct and clean power supply for the load.

[0065] Characteristics: Its driving capability (power supply duration) depends on the capacity of the first energy storage unit (EC1) and the second energy storage unit (EC2). Discharge time is determined by capacity, start / stop voltage, and load current.

[0066] Operating mode: The two units work alternately under time-sharing control. When one unit is discharging for the load, the other unit is charging through an external power source, thus achieving continuous energy replenishment.

[0067] 2. Time-sharing control and isolation module

[0068] Core functions:

[0069] Time-sharing control: controls the switching of charging and discharging states between the two energy storage units.

[0070] Electrical isolation: Physically disconnecting or connecting the circuit between the external power supply, the energy storage module and the load is the key to achieving ultra-high PSRR (110dB~140dB).

[0071] Workflow:

[0072] Initial state: The module disconnects the energy storage module from the load and directs the external power supply to the first energy storage unit (EC1) for charging.

[0073] Start-up state: When EC1 is fully charged, the pre-charge and start-up module sends a signal to trigger the trigger and state holding module. Subsequently, this module receives the control signal sent by it, immediately switches the internal switch state, connects the fully charged EC1 to the load to start discharging, and simultaneously switches the external power supply to charge the second energy storage unit (EC2).

[0074] 3. Triggering and State Preservation Module

[0075] Function: Receives a trigger signal and outputs a stable control signal to drive the time-sharing switch to switch, and can lock and maintain this state until the next trigger.

[0076] Implementation: A rising-edge triggered D flip-flop is used to ensure that each valid trigger signal causes a definite state to flip and remain.

[0077] Trigger source:

[0078] Startup trigger: Originates from the precharge and startup modules, marking the first system startup.

[0079] Switching trigger: from the voltage detection module, indicating that the charging / discharging unit needs to be switched to maintain the output voltage.

[0080] 4. Voltage detection module

[0081] Function: Continuously monitors the voltage supplied to the load.

[0082] Control logic: When the output voltage is detected to have dropped to the minimum voltage required for normal load operation (e.g., 1.8V), a trigger signal is immediately output to the trigger and state holding module. This will initiate a switching process, switching the power supply task from the currently discharging energy storage unit (e.g., EC1) to another fully charged unit (e.g., EC2).

[0083] 5. Transient Suppression and Filtering Networks

[0084] Transient suppression module:

[0085] Problem: High-frequency, high-voltage transient pulses (e.g., ±0.5V to ±1V, pulse width 1ns to 50ns) are generated during the switching of time-sharing switches.

[0086] Solution: Use a TVS diode (such as SMAJ5.0A) to clamp the pulse amplitude and suppress it within a safe range of ±0.5V / 10ns.

[0087] CLC filter network:

[0088] Function: It is divided into preamplifier and postamplifier, each with its own emphasis.

[0089] Pre-stage filtering: mainly filters out noise from the transient suppression module and external power supply.

[0090] Post-stage filtering: Located at the output, it mainly prevents useful signals from the load (such as in RF LNA applications) from being lost through power path leakage, while further filtering out power ripple.

[0091] Effect: The combined effect of multi-stage filtering achieves an extremely low final output noise level of 0.5μVrms to 5μVrms.

[0092] Parameter establishment:

[0093] The low-pass filter cutoff frequency of the CLC filter network is given by formula F. C =1 / (2π*√(L1*(C1*C2) / (C1+C2))) is determined, where F CThe values ​​represent the cutoff frequency, L1 represents the inductor that meets the current and self-resonant frequency requirements, and C1 and C2 represent the capacitors that meet ESR and other requirements. For example: L1 = 4.7nH (high Q value, high SRF self-resonant frequency RF inductor (metal powder core or amorphous core is best, ceramic or ferrite core can be substituted if SRF is met)), C1 = C2 = 4.7pF (COG capacitor with ESR below 5mΩ); the values ​​of L and C need to consider the actual impedance value and the parasitic distribution parameters of the wiring layout to avoid actual F C The value offset and the selection of the cutoff frequency should ensure that the required frequency attenuation is more than 20dB. Multi-stage filtering can be used.

[0094] The impedance of the CLC filter network is determined by the formula: Z0=√(L / (C1*C2 / (C1+C2))).

[0095] The constant current discharge time of the energy storage module is given by t = C(V). START -V END ) / I is determined, where I is the discharge current.

[0096] The ripple attenuation coefficient of the CLC filter network is given by the formula: r = 3615 / (C1 L C2 R) L The values ​​of C1 and C2 are determined, where C1 and C2 represent capacitance values ​​(unit: Farad F), typically used in parallel branches; L represents inductance value (unit: Henry H), used as a series element; R L This indicates the load resistance (unit: ohms Ω), which affects the output characteristics. Attached Figure Description

[0097] Figure 1 The diagram shows the composition and connection relationship of the present invention, wherein (1) is a pre-charging and start-up module, (2) is an energy storage module, (3) is a time-division control and isolation module, (4) is a transient suppression module, (5) is a triggering and state holding module, (6) is a voltage detection module, and (7) is a CLC filter network.

[0098] Figure 2 In one embodiment of the present invention, EC1 is a first energy storage unit, EC2 is a second energy storage unit, SPDT1 is a first switching switch, SPDT2 is a second switching switch, START1 is a start button, and U1 is a rising edge triggered D flip-flop for triggering and state holding.

[0099] Figure 3 The diagram shows the composition of the energy storage module, time-sharing control and isolation module of the present invention. In the diagram, EC1 is the first energy storage unit, EC2 is the second energy storage unit, SPDT1 is the first switching switch, SPDT2 is the second switching switch, EC1 and EC2 together form the energy storage module, and SPDT1 and SPDT2 together form the time-sharing control and isolation module. Example

[0100] Appendix Figure 2 As a specific embodiment of the present invention, its components are as follows:

[0101] The energy storage module (2) is composed of a first energy storage unit (EC1) and a second energy storage unit (EC2), and EC1 and EC2 are 10F / 2.7V supercapacitors of the same specification;

[0102] The first switching switch (SPDT1) and the second switching switch (SPDT2) together form a time-sharing control and isolation module (3);

[0103] The pre-charge and start-up module (1) consists of nine components: ZD2 Zener diode, SD2 Schottky diode, R1, R3, R6, R7, NPN transistor Q1, PMOS transistor Q2, and START1 micro switch button.

[0104] The trigger and state holding module (5) is composed of rising edge active D flip-flop U1, Schottky diode SD1, R4, R8, and C5.

[0105] The voltage detection module (6) is composed of NPN transistor Q3, Zener diode ZD1, R2, and R5.

[0106] The transient suppression module (4) consists of a transient voltage suppression diode (TVS1);

[0107] The CLC filter network (7) consists of L1, C1, C2 pre-stage filters and L2, C3, C4 post-stage filters.

[0108] In addition, J1-1 is the external power input terminal, and J2-1 is the output terminal for supplying power to the load.

[0109] The connection relationships in this embodiment are as follows: Terminal 1 of R1 is connected to input terminal J1-1; terminal 2 of R1 is connected to the normally closed terminal NC1 of SPDT1; terminal 2 of R1 is also connected to the normally open terminal NO2 of SPDT2; the negative terminals of EC1 and EC2 are both grounded; the positive terminal of EC1 is connected to the cathode of ZD2, terminal 1 of R6, the S terminal of Q2, and the COM1 terminal of SPDT1; the positive terminal of EC2 is connected to the COM2 terminal of SPDT2; terminal 2 of R3 is grounded; terminal 1 is connected to terminal 1 of R7 and the anode of ZD2; terminal 2 of R7 is connected to the base (B) of Q1; the emitter (E) of Q1 is grounded; the collector (C) of Q1 is connected to terminal 2 of R6 and the gate (G) of Q2; the drain (D) of Q2 is simultaneously connected to the anode A of SD2 and terminal 2 of START1; the NO1 terminal of SPDT1 is connected to the NC2 terminal of SPDT2 and then to terminal 1 of TVS1, and simultaneously to the anode A of SD1 and R6. Connect terminal 1 of 2, the positive terminal of C1, and terminal 1 of L1. Connect terminal 1 of SPDT1 to terminal 2 of SPDT2, and then connect them to the output terminal of U1. Connect the power supply terminal of U1 to the cathode K of SD2, the cathode K of SD1, and terminal 1 of R4. Connect the input terminal of U1 to terminal 1 of START1, terminal 1 of C5, terminal 1 of R8, terminal 2 of R4, and the collector (C) of Q3. Connect the base (B) of Q3 to the anode (A) of ZD1. The cathode K of ZD1 is connected to terminal 1 of R5 and terminal 2 of R2. The emitter of Q3 is grounded. Terminals 2 of R3, C5, R8, R5, and TVS1 are grounded. Terminal 2 of L1 is connected to terminal 1 of C2, C3, and L2. Terminal 2 of L2 is connected to terminal 1 of C4 and the output terminal J2-1. The negative terminal of C1, terminal 2 of C2, terminal 2 of C3, and terminal 2 of C4 are grounded.

[0110] The operation of the time-sharing control and isolation module is as follows: In the initial state, the energy storage module EC1 or EC2 needs to be charged. At this time, the control terminals CTR1 and CTR2 of the time-sharing control and isolation modules SPDT1 and SPDT2 are both at a low level, and the COM terminals of SPDT1 and SPDT2 are connected to their corresponding NC terminals. This embodiment is designed to start operation only when EC1 is fully charged. The COM1 terminal of SPDT1 is connected to the normally closed terminal of NC1 and is disconnected from the normally open terminal of NO1. The energy of the energy storage module EC1 cannot be transferred to the load. However, the energy from the input terminal J1-1 is current-limited by resistor R1 and then passes through the normally closed connection terminal of NC1 of SPDT1, and then through the COM1 terminal of SPDT1 to charge EC1. When EC1 is charged to a certain voltage, such as 2.7V, Zener diode ZD2 switches from the cutoff state to the conduction state. The electrical energy on EC1 discharges through ZD2 and R3. After ZD2 switches to the Zener state, when the voltage across R3 rises to the conduction voltage of Q1, Q1 conducts, and current flows through R6. The voltage at the gate (G) terminal of Q2 is lower than the voltage at the source (S) terminal, which meets the conduction condition of Q2, thus causing Q2 to conduct. The charging energy on EC1 can then discharge smoothly through Q2. Finally, U1 obtains the voltage required for normal operation through Q2 and SD2.

[0111] After U1 receives its normal operating voltage, its output remains at a low voltage. SPDT1 remains unchanged. When the START1 button is pressed, a rising edge trigger pulse is received at the U1 input. The U1 output immediately changes from a low voltage state to a high voltage state. C5 is used to eliminate jitter and other disturbances generated by START1, preventing false triggering of U1. The change in the output state of U1 causes a change in the CTR1 and CTR2 voltages of SPDT1 and SPDT2. After SPDT1's CTR1 goes high, COM1 switches to its normally open connection with NO1, and the energy of EC1 is successfully transferred to the output J2-1, energizing the load. After SPDT2's CTR2 goes high, COM2 switches to its normally open connection with NO2. Because NO2 is connected to R1, EC2 enters a pre-charge state.

[0112] The working process after startup is as follows: Assuming that the linkage control terminals CTR1 and CTR2 of the time-sharing control and isolation modules SPDT1 and SPDT2 are at a high level, this high level is output by the output terminal of the trigger and state holding module U1, that is, U1 outputs a high level. At this time, the COM1 terminal of SPDT1 is connected to NO1, and NO1 is connected to the load. At this time, EC1 discharges to the load through SPDT1. The voltage on EC1 will gradually decrease as the discharge time progresses, and the voltage obtained on the load will also decrease accordingly. The COM2 terminal of SPDT2 is connected to NO2, and NO2 is connected to R1. At this time, EC2 is charged through SPDT2 and R1. R1 is a current-limiting resistor, and its resistance value is set according to the charging time being less than the discharging time. The voltage on EC2 will gradually increase as the charging time progresses until it is fully charged. The value of R1 will determine the time required for full charging. The value of R1 should be selected according to the actual application. When the voltage across EC1 (output voltage) or TVS1 falls below a certain level (e.g., 1.8V), due to the voltage divider effect of ZD1, R2, and R5, the voltage required for Q3's saturation between its base and emitter cannot be reached. Q3 exits saturation and cuts off, and the collector (C) of Q3 changes from low to high. Since the collector of Q3 is connected to the trigger terminal of U1, the trigger and state holding module U1 detects the rising edge of the high level and is immediately triggered. The output of U1 quickly changes from a high level to a low level. The linkage control terminals CTR1 and CTR2 of the time-sharing control and isolation modules SPDT1 and SPDT2 change from high to low, switching the circuit. Thus, EC1 switches from discharging to charging, while EC2 switches from charging to discharging the load. This process repeats continuously, ensuring continuous power supply to the load.

[0113] In this embodiment, a 5mA current is used to discharge the load from a fully charged state to 1.8V. In actual testing, after a single supercapacitor continuously supplies power for 30 minutes, it automatically switches to another pre-charged supercapacitor.

[0114] To achieve precise voltage control, the voltage detection module consisting of Q3, ZD1, R2, and R5 can be implemented using a precise integrated circuit; the pre-charge and start-up module consisting of ZD2 Zener diode, SD2 Schottky diode, R1, R3, R6, R7, NPN transistor Q1, PMOS transistor Q2, and START1 microswitch can be implemented using an integrated circuit.

[0115] It should be noted that the supercapacitors (EC1, EC2) used in the first and second energy storage units of the energy storage module of this invention are only preferred embodiments of the energy storage module. The supercapacitors can achieve output noise below 1uVrms. Without departing from the core concept of this invention, the energy storage module can be implemented using other types of energy storage components, including but not limited to: lithium battery packs (including lithium-ion batteries, lithium polymer batteries, etc.), thin-film capacitors, Faraday quasi-capacitors, and other electronic components with energy storage characteristics. Such alternatives should meet the following requirements: rechargeable and rechargeable characteristics, and discharge current capability ≥1. load (Load demand current), self-discharge rate ≤ 5% / day (at 25℃). When using different energy storage elements, R1 in this embodiment should be changed accordingly based on the actual charging characteristics of the device.

Claims

1. A noise suppression circuit for dual energy storage units based on time-division control and dynamic isolation, characterized in that, include: The pre-charge and start-up module (1), energy storage module (2), time-sharing control and isolation module (3), transient suppression module (4), trigger and state holding module (5), voltage detection module (6), and CLC filter network (7); The energy storage module (2) includes a first energy storage unit (EC1) and a second energy storage unit (EC2) of the same specifications, both of which are grounded; The time-sharing control and isolation module (3) includes a first switching switch (SPDT1) and a second switching switch (SPDT2) that are mechanically or electrically linked; The connection relationship is as follows: The positive terminal of the first energy storage unit (EC1) is connected to the input terminal of the pre-charging and starting module (1) and the common terminal (COM1) of the first switching switch (SPDT1); The positive terminal of the second energy storage unit (EC2) is connected to the common terminal (COM2) of the second switching switch (SPDT2); The normally closed terminal (NC1) of the first switching switch (SPDT1) is connected to the normally open terminal (NO2) of the second switching switch (SPDT2), and both are connected to the external power supply input; The normally open terminal (NO1) of the first switching switch (SPDT1) is connected to the normally closed terminal (NC2) of the second switching switch (SPDT2), and they are both connected to the input terminal of the transient suppression module (4); The control terminals of the first switching switch (SPDT1) and the second switching switch (SPDT2) are connected in parallel and then connected to the output terminal of the triggering and state holding module (5); The output terminal of the pre-charging and start-up module (1) is connected to the power supply terminal and the trigger terminal of the trigger and status holding module (5); The output terminal of the transient suppression module (4) is connected to the input terminal of the CLC filter network (7) and the input terminal of the voltage detection module (6); The output terminal of the voltage detection module (6) is connected to the trigger terminal of the trigger and state holding module (5); The output of the CLC filter network (7) is used to connect to the load.

2. The noise suppression circuit for a dual energy storage unit based on time-division control and dynamic isolation according to claim 1, characterized in that: The triggering and state holding module (5) is implemented by a rising edge triggered D flip-flop. Its input receives the start trigger signal from the pre-charge and start module (1) and the switching trigger signal from the voltage detection module (6). Its output outputs a stable level signal to control the state switching and holding of the time-division control and isolation module (3).

3. The noise suppression circuit for a dual energy storage unit based on time-division control and dynamic isolation according to claim 1, characterized in that: The time-sharing control and isolation module (3) is configured to have two operating states: Initial state: The common terminal (COM) of the first switching switch (SPDT1) is connected to the normally closed terminal (NC), enabling the external power supply to charge the first energy storage unit (EC1); Operating state: Under the control of the triggering and state holding module (5), the first switching switch (SPDT1) and the second switching switch (SPDT2) are switched synchronously, so that the common terminal (COM) of one energy storage unit is connected to the normally open terminal (NO) to discharge to the load, while the common terminal (COM) of the other energy storage unit is connected to the normally open terminal (NO) to access an external power source for charging.

4. The noise suppression circuit for a dual energy storage unit based on time-division control and dynamic isolation according to claim 1, characterized in that: The CLC filter network (7) contains two or more CLC filter units. The pre-stage filter is mainly used to filter out noise interference from the outside, and the post-stage filter is mainly used to block useful signals from the load from leaking through the power path.

5. The noise suppression circuit for a dual energy storage unit based on time-division control and dynamic isolation according to claim 1, characterized in that: The transient suppression module (4) is composed of transient voltage suppression devices (TVS tube / ESD tube) and is used to clamp the high-frequency high voltage pulse generated when the time-sharing control and isolation module (3) switches, and suppress its amplitude within the safe range of the load.

6. The noise suppression circuit for a dual energy storage unit based on time-division control and dynamic isolation according to claim 1, characterized in that: The pre-charge and start-up module (1) is used to monitor the voltage of the first energy storage unit (EC1) and only outputs a trigger signal and supplies power to the trigger and status holding module (5) when its voltage reaches a preset value, thereby starting the circuit.

7. The noise suppression circuit for a dual energy storage unit based on time-division control and dynamic isolation according to claim 1, characterized in that: The voltage detection module (6) is used to monitor the output voltage in real time. When the output voltage is lower than the minimum operating voltage required by the load, it outputs a rising edge trigger signal to the trigger and state holding module (5) to start the charging and discharging state switching of the energy storage unit.

8. A noise suppression circuit for a dual energy storage unit based on time-division control and dynamic isolation according to any one of claims 1 to 7, characterized in that: The first energy storage unit (EC1) and the second energy storage unit (EC2) in the energy storage module (2) are supercapacitors, lithium batteries, thin film capacitors or Faraday pseudocapacitors.

9. An electronic device, characterized in that, Includes a dual energy storage unit noise suppression circuit based on time-division control and dynamic isolation as described in any one of claims 1 to 8, used to provide ultra-low noise power for precision loads in the device.

Images