Medical implantable emi rejection dc-dc circuit based on shared inductance

Abstract

The application provides a medical implantable EMI suppression DC-DC circuit based on a shared inductor, comprising: a logic control module, which is used for generating a logic instruction based on an input control signal and generating a drive control signal based on the logic instruction and sending the drive control signal to a shared inductor module; the shared inductor module, which is used for controlling the turn-off of multiple inductors based on the drive control signal, so that the multiple inductors are simultaneously connected or selectively connected to a transformer main circuit module; the transformer main circuit module, which is used for obtaining an output voltage and an output current based on an input voltage, a conduction time and the resistance of the multiple inductors and sending the output voltage and the output current to an active EMI suppression module; and the active EMI suppression module, which is used for generating a ripple current which is opposite to the output current and has zero direct current, so as to eliminate the ripple of the output current and the output voltage. The application can simultaneously meet the requirements of small size, low power consumption, high efficiency, high reliability, low EMI and the like of an implantable circuit.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit technology, and more particularly to a medical implantable EMI suppression DC-DC circuit based on a shared inductor. Background Technology

[0002] With the development of medical technology and scientific progress, people's attention to the medical and health field has gradually deepened. The development of technology and demand has promoted the development of various medical devices. Moore's Law for integrated circuits, as a trend in electronic technology and product miniaturization, has further promoted the development of active implantable medical devices, miniaturizing large devices and replacing some drug treatments. Among the research on various implantable medical devices, neurostimulators, as a major direction, have received close attention and extensive research.

[0003] Neurostimulators use electrical signals as therapeutic "drugs" applied to muscles or nerves. Low-frequency electrical pulses of a certain intensity are applied to organs or limbs with functional problems to help regulate muscle or nerve function, thereby achieving a therapeutic effect. Therefore, this treatment method is medically termed Functional Electrical Stimulation (FES) and is primarily used in various neurological and muscular rehabilitation settings.

[0004] The development of integrated circuits has greatly advanced the development of implantable medical devices, miniaturizing large devices to replace drug therapy. Neurostimulators are widely used in implantable medical devices; however, they have high power requirements, needing to simultaneously meet the requirements of small size, low power consumption, high efficiency, high reliability, and low EMI. Summary of the Invention

[0005] This invention provides a medical implantable EMI suppression DC-DC circuit based on a shared inductor, which solves the problem that the power supply in the prior art cannot meet multiple requirements, and achieves the simultaneous satisfaction of the requirements of small size, low power consumption, high efficiency, high reliability and low EMI of implantable circuits.

[0006] This invention provides a medical implantable EMI suppression DC-DC circuit based on a shared inductor, comprising: a logic control module, a shared inductor module, a converter main circuit module, and an active EMI suppression module connected in sequence;

[0007] The logic control module is used to generate logic instructions based on the input control signals, and generate drive control signals based on the logic instructions to send to the shared inductor module.

[0008] The shared inductor module is used to control the turn-off of multiple inductors based on the drive control signal, so that multiple inductors can be connected to the converter main circuit module simultaneously or selectively.

[0009] The converter main circuit module is used to obtain the output voltage and output current based on the input voltage, conduction time and the resistance of multiple inductors, and send them to the active EMI suppression module.

[0010] The active EMI suppression module is used to generate a ripple current that is opposite to the output current and has zero DC current based on the output current, so as to eliminate the ripple of the output current and output voltage.

[0011] According to the present invention, a medical implantable EMI suppression DC-DC circuit based on a shared inductor further includes an error processing module, which is connected to the converter main circuit module;

[0012] The error processing module is used to perform differential-mode amplification, error processing, and error comparison based on the output voltage of the converter main circuit module, and to obtain a control signal with fixed frequency and adjustable duty cycle, which is returned to the logic control module to adjust the output voltage of the converter.

[0013] According to the present invention, a medical implantable EMI suppression DC-DC circuit based on a shared inductor is provided. The main circuit module of the converter includes a Buck converter circuit and a Buck-Boost converter circuit. The active EMI suppression module includes a Buck active suppression circuit and a Buck-Boost active suppression circuit. The Buck converter circuit is connected to the Buck active suppression circuit, and the Buck-Boost converter circuit is connected to the Buck-Boost active suppression circuit.

[0014] The Buck converter and the Buck-Boost converter share the shared inductor module, and based on the inductor's off status in the shared inductor module, they can be connected to multiple inductors simultaneously or selectively.

[0015] According to the present invention, a medical implantable EMI suppression DC-DC circuit based on a shared inductor is provided, wherein the Buck-Boost converter circuit includes a first switching transistor, a second switching transistor, a first inductor, and a first output capacitor;

[0016] The first switching transistor is connected in series with the second switching transistor and connected to the Buck-Boost active suppression circuit; one end of the first inductor is connected between the first switching transistor and the second switching transistor, and the other end is grounded; one end of the first output capacitor is connected between the second switching transistor and the Buck-Boost active suppression circuit, and the other end is grounded.

[0017] According to the present invention, a medical implantable EMI suppression DC-DC circuit based on a shared inductor is provided, wherein the Buck-Boost active suppression circuit includes a first blocking capacitor, a third switching transistor, a fourth switching transistor, and a second inductor;

[0018] The first blocking capacitor is connected to the second switching transistor, and the first blocking capacitor, the third switching transistor, and the fourth switching transistor are connected in series. One end of the second inductor is connected between the third and fourth switching transistors, and the other end is grounded.

[0019] According to the present invention, a medical implantable EMI suppression DC-DC circuit based on a shared inductor is provided, wherein the Buck converter circuit includes a fifth switch, a sixth switch, a third inductor, and a second output capacitor;

[0020] The fifth and sixth switching transistors are connected in series, with the other end of the fifth switching transistor connected to the input voltage and the other end of the sixth switching transistor grounded; one end of the third inductor is connected between the fifth and sixth switching transistors, and the other end is connected to the Buck active suppression circuit; one end of the second output capacitor is connected between the third inductor and the Buck active suppression circuit, and the other end is grounded.

[0021] According to the present invention, a medical implantable EMI suppression DC-DC circuit based on a shared inductor is provided, wherein the Buck active suppression circuit includes a seventh switch, an eighth switch, a second blocking capacitor, and a fourth inductor;

[0022] The seventh and eighth switches are connected in series, with the other end of the seventh switch connected to the input voltage and the other end of the eighth switch grounded; the second blocking capacitor is connected in series with the fourth inductor, with the other end of the second blocking capacitor connected to the third inductor, and the other end of the fourth inductor connected between the seventh and eighth switches.

[0023] According to the present invention, a medical implantable EMI suppression DC-DC circuit based on a shared inductor is provided, wherein the logic control module includes a control submodule and a drive submodule;

[0024] The control submodule is used to generate logical instructions based on the input control signals and send them to the driver submodule.

[0025] The driving submodule is used to generate a driving control signal based on the logic instruction and send it to the shared inductor module.

[0026] According to the present invention, a medical implantable EMI suppression DC-DC circuit based on a shared inductor is provided, wherein the error processing module includes an error amplifier, a comparator, and a ramp generator;

[0027] The error amplifier is used to sample the output voltage of the converter main circuit module and amplify it differentially with the reference voltage generated by the bandgap reference voltage source to obtain an error signal.

[0028] The ramp wave generator is used to generate sawtooth waves with a fixed frequency.

[0029] The comparator is used to compare the error signal with the sawtooth wave to obtain a control signal with a fixed frequency and adjustable duty cycle, which is then returned to the logic control module to adjust the output voltage of the converter.

[0030] This invention also provides a medical implantable EMI suppression method based on a shared inductor, used in any of the above-described medical implantable EMI suppression DC-DC circuits based on a shared inductor, comprising:

[0031] The logic control module generates logic instructions based on the input control signals and sends the logic instructions to the shared inductor module.

[0032] The shared inductor module controls the shutdown of multiple inductors based on the drive control signal, so that multiple inductors can be connected to the converter main circuit module simultaneously or selectively.

[0033] The converter's main circuit module obtains the output voltage and output current based on the input voltage, conduction time, and the resistance of multiple inductors, and sends them to the active EMI suppression module.

[0034] The active EMI suppression module generates a ripple current that is inversely phase to the output current and has zero DC current based on the output current, thereby eliminating the ripple of the output current and output voltage.

[0035] This invention provides a medical implantable EMI suppression DC-DC circuit based on a shared inductor. It generates logic instructions based on an input control signal and sends these instructions to a shared inductor module. The drive control signal then controls the shutdown of multiple inductors, allowing them to be simultaneously or selectively connected to the converter's main circuit module. Based on the input voltage, conduction time, and the resistance of the inductors, the output voltage and output current are obtained and sent to an active EMI suppression module. Finally, the active EMI suppression module generates a ripple current with zero DC current and opposite phase to the output current to eliminate ripple in the output current and voltage. This invention simultaneously meets the requirements of small size, low power consumption, high efficiency, high reliability, and low EMI for implantable circuits. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the structure of the medical implantable EMI suppression DC-DC circuit based on a shared inductor provided by the present invention;

[0038] Figure 2 This is a schematic diagram of the structure of the shared inductor module provided by the present invention;

[0039] Figure 3 This is one of the circuit diagrams of the medical implantable EMI suppression DC-DC circuit based on a shared inductor provided by the present invention;

[0040] Figure 4 This is the second circuit diagram of the medical implantable EMI suppression DC-DC circuit based on a shared inductor provided by the present invention;

[0041] Figure 5 This is a schematic diagram of the output current of the Buck-Boost active EMI suppression circuit.

[0042] Figure 6 This is the third circuit diagram of the medical implantable EMI suppression DC-DC circuit based on a shared inductor provided by the present invention;

[0043] Figure 7 This is a schematic diagram of the output current of the Buck active EMI suppression circuit.

[0044] Figure 8 This is the current waveform flowing through the final shared inductor in this invention;

[0045] Figure 9 This is a flowchart illustrating the medical implantable EMI suppression method based on a shared inductor provided by the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0047] The following is combined with Figures 1-9This invention describes a medical implantable EMI suppression DC-DC circuit based on a shared inductor.

[0048] Reference Figure 1 The present invention provides a medical implantable EMI suppression DC-DC circuit based on a shared inductor, comprising: a logic control module 110, a shared inductor module 120, a converter main circuit module 130 and an active EMI suppression module 140 connected in sequence.

[0049] The logic control module 110 is used to generate logic instructions based on the input control signals, and generate drive control signals based on the logic instructions and send them to the shared inductor module.

[0050] The shared inductor module 120 is used to control the turn-off of multiple inductors based on the drive control signal, so that multiple inductors can be connected to the converter main circuit module simultaneously or selectively.

[0051] The converter main circuit module 130 is used to obtain the output voltage and output current based on the input voltage, conduction time and the resistance of multiple inductors and send them to the active EMI suppression module.

[0052] The active EMI suppression module 140 is used to generate a ripple current that is opposite to the output current and has zero DC current based on the output current, so as to eliminate the ripple of the output current and output voltage.

[0053] Specifically, when the circuit starts up, the logic control module generates drive control signals based on the input control signals to control the turn-off of inductors S1, S2, S3, and S4 in the shared inductor module. This allows multiple shared inductors to be simultaneously or selectively connected to the converter's main circuit module, generating output voltage and output current. Then, an active EMI suppression module is connected to generate a ripple current that is inversely phase to the output current and has zero DC current. This precisely eliminates the output current ripple and also effectively eliminates the output voltage ripple, thereby actively reducing the EMI and output noise of the DC-DC converter.

[0054] Reference Figure 2 In this embodiment, the shared inductor module is controlled by a signal from the control module. Since the DC-DC converter only needs to use the inductor for a portion of the time based on the load power.

[0055] In this embodiment, both the Buck and Buck-Boost converters operate in DCM mode with a switching frequency of 200kHz and use voltage-mode PWM control for voltage regulation. Their function is to provide a stable ±3.3V supply voltage to the load simultaneously or separately, with a total power consumption of <10mW, output ripple within 10mV, and an efficiency of up to 90% under heavy load. Furthermore, the introduction of a shared inductor reduces the overall circuit size to within 5mm. 2 Within.

[0056] The shared inductor module can use a fixed inductor of model LQM18DN470M70L manufactured by Murata, with an inductance of L=47μH, dimensions of 1.6mm*0.8mm*0.8mm, and on-resistance Rdcr=2.55Ω.

[0057] This invention provides a medical implantable EMI suppression DC-DC circuit based on a shared inductor. It generates logic instructions based on an input control signal and sends these instructions to a shared inductor module. The drive control signal then controls the shutdown of multiple inductors, allowing them to be simultaneously or selectively connected to the converter's main circuit module. Based on the input voltage, conduction time, and the resistance of the inductors, the output voltage and output current are obtained and sent to an active EMI suppression module. Finally, the active EMI suppression module generates a ripple current with zero DC current and opposite phase to the output current to eliminate ripple in the output current and voltage. This invention simultaneously meets the requirements of small size, low power consumption, high efficiency, high reliability, and low EMI for implantable circuits.

[0058] Reference Figure 3 , Figure 3 This is a schematic diagram of the internal overall circuit structure of the medical implantable EMI suppression DC-DC circuit based on a shared inductor in this embodiment. Compared with the above embodiment, it also includes an error processing module 210, which is connected to the converter main circuit module 220;

[0059] The error processing module 210 is used to perform differential-mode amplification, error processing, and error comparison based on the output voltage of the converter main circuit module 220, and to obtain a control signal with fixed frequency and adjustable duty cycle, which is returned to the logic control module 230 to adjust the output voltage of the converter.

[0060] The error processing module includes an error amplifier 211, a comparator 212, and a ramp generator 213;

[0061] The error amplifier 211 is used to sample the output voltage of the converter main circuit module 214 and amplify it differentially with the reference voltage generated by the bandgap reference voltage source to obtain an error signal.

[0062] The ramp generator 213 is used to generate sawtooth waves with a fixed frequency.

[0063] The comparator 212 is used to compare the error signal with the sawtooth wave to obtain a control signal with a fixed frequency and adjustable duty cycle, which is then returned to the logic control module 230 to adjust the output voltage of the converter.

[0064] Based on the above embodiments, the logic control module 230 includes a control submodule 231 and a drive submodule 232;

[0065] The control submodule 231 is used to generate logic instructions based on the input control signals and send them to the drive submodule.

[0066] The driving submodule 232 is used to generate a driving control signal based on the logic instruction and send it to the shared inductor module 240.

[0067] Specifically, after the circuit is started, the error amplifier samples the output voltage of the Buck and Buck-Boost converters and amplifies it differentially with the reference voltage generated by the bandgap reference voltage source. The ramp generator generates a sawtooth wave with a fixed frequency. Then, the comparator compares this error signal with a sawtooth wave with a fixed frequency, thereby obtaining a control signal with a fixed frequency and adjustable duty cycle to initially adjust the output voltage of the converter.

[0068] It should be noted that the comparator in this embodiment is a PWM comparator.

[0069] Based on the above embodiments, the converter main circuit module includes a Buck converter circuit and a Buck-Boost converter circuit, the active EMI suppression module includes a Buck active suppression circuit and a Buck-Boost active suppression circuit, the Buck converter circuit is connected to the Buck active suppression circuit, and the Buck-Boost converter circuit is connected to the Buck-Boost active suppression circuit.

[0070] The Buck converter and the Buck-Boost converter share the shared inductor module, and based on the inductor's off status in the shared inductor module, they can be connected to multiple inductors simultaneously or selectively.

[0071] The Buck-Boost converter circuit includes a first switching transistor, a second switching transistor, a first inductor, and a first output capacitor;

[0072] The first switching transistor is connected in series with the second switching transistor and connected to the Buck-Boost active suppression circuit; one end of the first inductor is connected between the first switching transistor and the second switching transistor, and the other end is grounded; one end of the first output capacitor is connected between the second switching transistor and the Buck-Boost active suppression circuit, and the other end is grounded.

[0073] The Buck-Boost active suppression circuit includes a first blocking capacitor, a third switching transistor, a fourth switching transistor, and a second inductor;

[0074] The first blocking capacitor is connected to the second switching transistor, and the first blocking capacitor, the third switching transistor, and the fourth switching transistor are connected in series. One end of the second inductor is connected between the third and fourth switching transistors, and the other end is grounded.

[0075] Reference Figure 4 On the left is the Buck-Boost converter circuit 410 in this embodiment, which consists of two switching transistors: a first switching transistor MP1 and a second switching transistor MN1, a first inductor L1, and an output capacitor C. 01 Composition. The right side shows the Buck-Boost active EMI suppression circuit 420 in this embodiment, consisting of two switching transistors: the third switching transistor MP2 and the fourth switching transistor MN2, and a blocking capacitor C. S1 And a second inductor L S1 composition.

[0076] It should be noted that both circuit modules operate in DCM mode at a frequency of 200kHz. This is because they are used in conjunction with a shared inductor, and operating at too high a frequency would cause the current in the shared inductor to become unstable. The function of the Buck-Boost active EMI suppression circuit is to generate an AC current that is opposite in phase to the output current in order to precisely eliminate the ripple of the inductor current.

[0077] The following explanations are provided for Buck-Boost converter circuits and Buck-Boost active EMI suppression circuits:

[0078] 1) All switching transistors MP1, MP1, MN2, and MN2 are ideal.

[0079] 2)C 01 and C S1 The voltage V between OUT1 and V LS1 It is a constant value, and C S1 < <C 01 .

[0080] 3) L1 and L S1 The inductance is the same.

[0081] 4) The conduction time of MP1 and MN2 is D 1r T S The conduction time of MN1 and MP2 is D 1f T S T S It is the switching cycle, D 1r It is the duty cycle of MP1.

[0082] When switching transistor MP1 or MN1 is turned on, the voltage V across inductor L1 is... L1 V in or V OUT1 According to the formula for the Buck-Boost converter operating in DCM mode:

[0083] V in D 1r =-V out1 D 1f (1)

[0084]

[0085]

[0086]

[0087]

[0088] V can be calculated out1 With V in Relationship:

[0089]

[0090] Similarly, when switching transistor MP2 or MN1 is turned on, L S2 V on LS2 The voltages are respectively -(V) CS1 +V OUT1 ) or V in Therefore, V CS1 The DC value can be calculated as follows:

[0091]

[0092] To prevent direct current from flowing through inductor L S1 Using blocking capacitor C S1 Thus, the current I LS1 The DC component is considered zero. When switches MN1 and MP2 are off and MP1 and MN2 are on, the inductor voltage V... L1 and V LS1 It can be represented as:

[0093] VL1 =V in D 1r (8)

[0094]

[0095] From the inductor voltage V L1 and V LS1 The specific formula can be derived by adjusting the parameters to make the inductor voltage V L1 and V LS1 They have the same amplitude but different phase. Under the same inductance, the current fluctuations in the inductor can be accurately canceled out by the current fluctuations in the inductor. This is because the output current is the inductor current I. L1 and I LS1 The sum of all the currents, so the output current equals I. OUT1 The DC component.

[0096] Reference Figure 5 , Figure 5 This is a schematic diagram of the output current of the Buck-Boost active EMI suppression circuit. As can be seen from the figure, the output current results show that this circuit can effectively eliminate current ripple, and the output voltage ripple is also well eliminated.

[0097] Based on the above embodiments, the Buck converter circuit includes a fifth switch, a sixth switch, a third inductor, and a second output capacitor;

[0098] The fifth and sixth switching transistors are connected in series, with the other end of the fifth switching transistor connected to the input voltage and the other end of the sixth switching transistor grounded; one end of the third inductor is connected between the fifth and sixth switching transistors, and the other end is connected to the Buck active suppression circuit; one end of the second output capacitor is connected between the third inductor and the Buck active suppression circuit, and the other end is grounded.

[0099] The Buck active suppression circuit includes a seventh switch, an eighth switch, a second blocking capacitor, and a fourth inductor;

[0100] The seventh and eighth switches are connected in series, with the other end of the seventh switch connected to the input voltage and the other end of the eighth switch grounded; the second blocking capacitor is connected in series with the fourth inductor, with the other end of the second blocking capacitor connected to the third inductor, and the other end of the fourth inductor connected between the seventh and eighth switches.

[0101] Reference Figure 6 On the left is the Buck converter circuit 610 in this embodiment, which consists of two switching transistors: the fifth switching transistor MP3 and the sixth switching transistor MN3, as well as the third inductor L2 and the output capacitor C. 02The circuit consists of two switching transistors: the seventh transistor MP4 and the eighth transistor MN4, and a blocking capacitor C. The right side shows the BUCK active EMI suppression circuit 620, which comprises two switching transistors: the seventh transistor MP4 and the eighth transistor MN4, and a blocking capacitor C. S2 and an inductor L S2 Composition. The function of the BUCK active EMI suppression circuit is to generate alternating current to precisely eliminate the ripple of the inductor current.

[0102] The following explanations are provided for Buck converter circuits and Buck active EMI suppression circuits:

[0103] 1) All switching transistors MP3, MP4, MN3, and MN4 are ideal.

[0104] 2)C 02 and C S2 The voltage V between OUT2 and V LS2 It is a constant value, and C S2 < <C 02 .

[0105] 3) L2 and L S2 The inductance is the same.

[0106] 4) The conduction time of MP3 and MN4 is D 2r T S The conduction time of MN3 and MP4 is D. 2f T S T S It is the switching cycle, D 2r It's the duty cycle of the MP3 file.

[0107] When switching transistor MP3 or MN3 is turned on, the voltage V across inductor L2 is... L2 They are respectively (V) in -V OUT2 ) or -V OUT2 According to the formula for the BUCK converter operating in DCM mode:

[0108] (V in -V out2 )D 2r =V out2 D 2f (10)

[0109]

[0110]

[0111]

[0112]

[0113] V can be calculated out With V in Relationship:

[0114]

[0115] Similarly, when switching transistors MP4 or MN3 are turned on, L S2 V on LS2 The voltages are respectively -(V) CS2 +V OUT2 ) or V in –V CS2 -V OUT2 Then, V CS2 The DC value can be calculated as follows:

[0116]

[0117] To prevent direct current from flowing through inductor L S2 Using blocking capacitor C S2 Thus, the current I LS2 The DC component is considered zero. When switching transistors MN3 and MP4 are off, and MP3 and MN4 are on, the inductor voltage V... L2 and V LS2 It can be represented as:

[0118]

[0119]

[0120] From the inductor voltage V L2 and V LS2 The specific formula can be derived by adjusting the parameters to make the inductor voltage V L2 and V LS2 They have the same amplitude but different phase. Under the same inductance, the current fluctuations in the inductor can be accurately canceled out by the current fluctuations in the inductor. This is because the output current is the inductor current I. L2 and I LS2 The sum of all the currents, so the output current equals I. OUT2 The DC component.

[0121] Reference Figure 7 , Figure 7 This is a schematic diagram of the output current of the Buck active EMI suppression circuit. As can be seen from the figure, the output current results show that the circuit can effectively eliminate current ripple, and the output voltage ripple is also well eliminated.

[0122] Combination Figure 2 , Figure 5 and Figure 7The typical inductor utilization time and respective inductor current, request, and release waveforms of Buck-Boost and Buck converter circuits are shown. For a Buck converter with a clock frequency of 200kHz, the turn-on time is 0.055μs. The effect of the discontinuous conduction mode is clearly visible in the inductor current waveform: the inductor current waveform rises when the MP3 power transistor is turned on and drops to zero when the MN3 power transistor is turned on. Here, when the inductor current reaches zero, the Buck converter no longer needs an inductor until the start of the next clock cycle. For a Buck-Boost converter with a clock frequency of 200kHz, the inductor current waveform rises when the MP1 power transistor is turned on and drops to zero when the MN1 power transistor is turned on. The turn-on time is 0.055μs every 5μs.

[0123] Reference Figure 8 , Figure 8 This is the final current waveform flowing through the shared inductor. Based on the shared inductor module in this embodiment, the inductance utilization of the circuit system is very low, which makes it possible to share the inductor between the two converter circuits, allowing the Buck converter and the Buck-Boost converter to share a single inductor, thereby saving the overall size and cost of the DC-DC converter.

[0124] Reference Figure 9 The present invention also provides a method for medical implantable EMI suppression based on a shared inductor, comprising the following steps:

[0125] Step 910: The logic control module generates logic instructions based on the input control signals and sends the logic instructions to the shared inductor module.

[0126] Step 920: Control the shutdown of multiple inductors based on the drive control signal through the shared inductor module, so that multiple inductors are simultaneously or selectively connected to the converter main circuit module.

[0127] Step 930: The converter main circuit module obtains the output voltage and output current based on the input voltage, conduction time, and resistance of multiple inductors, and sends them to the active EMI suppression module.

[0128] Step 940: The active EMI suppression module generates a ripple current that is inversely phase to the output current and has zero DC current based on the output current, so as to eliminate the ripple of the output current and output voltage.

[0129] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A medical implantable EMI suppression DC-DC circuit based on a shared inductor, characterized in that, include: The logic control module, shared inductor module, converter main circuit module, and active EMI suppression module are connected in sequence. The logic control module is used to generate logic instructions based on the input control signals, and generate drive control signals based on the logic instructions to send to the shared inductor module. The shared inductor module is used to control the shutdown of multiple inductors based on the drive control signal, so that multiple inductors can be connected to the converter main circuit module simultaneously or selectively. The converter main circuit module is used to obtain the output voltage and output current based on the input voltage, conduction time and the resistance of multiple inductors, and send them to the active EMI suppression module. The active EMI suppression module is used to generate a ripple current that is opposite to the output current and has zero DC current based on the output current, so as to eliminate the ripple of the output current and output voltage. The converter main circuit module includes a Buck converter circuit and a Buck-Boost converter circuit, and the active EMI suppression module includes a Buck active suppression circuit and a Buck-Boost active suppression circuit. The Buck converter circuit is connected to the Buck active suppression circuit, and the Buck-Boost converter circuit is connected to the Buck-Boost active suppression circuit. The Buck converter and the Buck-Boost converter share the shared inductor module, and based on the inductor's off status in the shared inductor module, they can be connected to multiple inductors simultaneously or selectively.

2. The medical implantable EMI suppression DC-DC circuit based on a shared inductor according to claim 1, characterized in that, It also includes an error processing module, which is connected to the converter main circuit module; The error processing module is used to perform differential-mode amplification, error processing, and error comparison based on the output voltage of the converter main circuit module, and to obtain a control signal with fixed frequency and adjustable duty cycle, which is returned to the logic control module to adjust the output voltage of the converter.

3. The medical implantable EMI suppression DC-DC circuit based on a shared inductor according to claim 1, characterized in that, The Buck-Boost converter circuit includes a first switching transistor, a second switching transistor, a first inductor, and a first output capacitor; The first switching transistor is connected in series with the second switching transistor and connected to the Buck-Boost active suppression circuit; one end of the first inductor is connected between the first switching transistor and the second switching transistor, and the other end is grounded; one end of the first output capacitor is connected between the second switching transistor and the Buck-Boost active suppression circuit, and the other end is grounded.

4. The medical implantable EMI suppression DC-DC circuit based on a shared inductor according to claim 3, characterized in that, The Buck-Boost active suppression circuit includes a first blocking capacitor, a third switching transistor, a fourth switching transistor, and a second inductor. The first blocking capacitor is connected to the second switching transistor, and the first blocking capacitor, the third switching transistor, and the fourth switching transistor are connected in series. One end of the second inductor is connected between the third and fourth switching transistors, and the other end is grounded.

5. The medical implantable EMI suppression DC-DC circuit based on a shared inductor according to claim 1, characterized in that, The Buck converter circuit includes a fifth switch, a sixth switch, a third inductor, and a second output capacitor; The fifth and sixth switching transistors are connected in series, with the other end of the fifth switching transistor connected to the input voltage and the other end of the sixth switching transistor grounded; one end of the third inductor is connected between the fifth and sixth switching transistors, and the other end is connected to the Buck active suppression circuit; one end of the second output capacitor is connected between the third inductor and the Buck active suppression circuit, and the other end is grounded.

6. The medical implantable EMI suppression DC-DC circuit based on a shared inductor according to claim 5, characterized in that, The Buck active suppression circuit includes a seventh switch, an eighth switch, a second blocking capacitor, and a fourth inductor; The seventh and eighth switches are connected in series, with the other end of the seventh switch connected to the input voltage and the other end of the eighth switch grounded; the second blocking capacitor is connected in series with the fourth inductor, with the other end of the second blocking capacitor connected to the third inductor, and the other end of the fourth inductor connected between the seventh and eighth switches.

7. The medical implantable EMI suppression DC-DC circuit based on a shared inductor according to claim 1, characterized in that, The logic control module includes a control submodule and a driver submodule; The control submodule is used to generate logical instructions based on the input control signals and send them to the driver submodule. The driving submodule is used to generate a driving control signal based on the logic instruction and send it to the shared inductor module.

8. The medical implantable EMI suppression DC-DC circuit based on a shared inductor according to claim 2, characterized in that, The error processing module includes an error amplifier, a comparator, and a ramp generator; The error amplifier is used to sample the output voltage of the converter main circuit module and amplify it differentially with the reference voltage generated by the bandgap reference voltage source to obtain an error signal. The ramp wave generator is used to generate sawtooth waves with a fixed frequency. The comparator is used to compare the error signal with the sawtooth wave to obtain a control signal with a fixed frequency and adjustable duty cycle, which is then returned to the logic control module to adjust the output voltage of the converter.

9. A method for suppressing implantable medical EMI based on shared inductance, characterized in that, A medical implantable EMI suppression DC-DC circuit based on a shared inductor as described in any one of claims 1-8, comprising: The logic control module generates logic instructions based on the input control signals and sends the logic instructions to the shared inductor module. The shared inductor module controls the shutdown of multiple inductors based on the drive control signal, so that multiple inductors can be connected to the converter main circuit module simultaneously or selectively. The converter's main circuit module obtains the output voltage and output current based on the input voltage, conduction time, and the resistance of multiple inductors, and sends them to the active EMI suppression module. The active EMI suppression module generates a ripple current that is out of phase with the output current and has zero DC current based on the output current, so as to eliminate the ripple of the output current and output voltage. The converter main circuit module includes a Buck converter circuit and a Buck-Boost converter circuit, and the active EMI suppression module includes a Buck active suppression circuit and a Buck-Boost active suppression circuit. The Buck converter circuit is connected to the Buck active suppression circuit, and the Buck-Boost converter circuit is connected to the Buck-Boost active suppression circuit. The Buck converter and the Buck-Boost converter share the shared inductor module, and based on the inductor's off status in the shared inductor module, they can be connected to multiple inductors simultaneously or selectively.

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