CN210168018U - Variable gain amplifier and biological signal processing chip - Google Patents
Variable gain amplifier and biological signal processing chip Download PDFInfo
- Publication number
- CN210168018U CN210168018U CN201921149838.1U CN201921149838U CN210168018U CN 210168018 U CN210168018 U CN 210168018U CN 201921149838 U CN201921149838 U CN 201921149838U CN 210168018 U CN210168018 U CN 210168018U
- Authority
- CN
- China
- Prior art keywords
- variable gain
- gain amplifier
- circuit
- signal
- variable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
- A61B5/024—Detecting, measuring or recording pulse rate or heart rate
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/72—Signal processing specially adapted for physiological signals or for diagnostic purposes
- A61B5/7225—Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/45—Differential amplifiers
- H03F3/45071—Differential amplifiers with semiconductor devices only
- H03F3/45479—Differential amplifiers with semiconductor devices only characterised by the way of common mode signal rejection
- H03F3/45928—Differential amplifiers with semiconductor devices only characterised by the way of common mode signal rejection using IC blocks as the active amplifying circuit
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G3/00—Gain control in amplifiers or frequency changers without distortion of the input signal
- H03G3/20—Automatic control
- H03G3/30—Automatic control in amplifiers having semiconductor devices
- H03G3/3036—Automatic control in amplifiers having semiconductor devices in high-frequency amplifiers or in frequency-changers
- H03G3/3042—Automatic control in amplifiers having semiconductor devices in high-frequency amplifiers or in frequency-changers in modulators, frequency-changers, transmitters or power amplifiers
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F2200/00—Indexing scheme relating to amplifiers
- H03F2200/435—A peak detection being used in a signal measuring circuit in a controlling circuit of an amplifier
Abstract
The utility model discloses a variable gain amplifier and biological signal processing chip, variable gain amplifier includes variable gain amplifier circuit and detection control circuit, wherein variable gain amplifier circuit, including first variable gain control unit, second variable gain control unit and operational amplification circuit for amplify input signal and output amplification signal; the detection control circuit is used for detecting the amplification signal, comparing the peak value of the amplification signal with a preset range, and outputting and adjusting the gain control signals of the first variable gain control unit and the second variable gain control unit so as to adjust the gain of the variable gain amplifier. The utility model provides an embodiment effectively improves switched capacitor filter's response speed through variable gain amplifier circuit and detection control circuit, reduces the circuit and gets into the required time of stable work.
Description
Technical Field
The utility model relates to an integrated circuit technical field especially relates to a variable gain amplifier and biological signal processing chip.
Background
In recent years, with the popularization of health-care wearable devices, chips for detecting and processing biological signals have a wide development prospect. In order to better analyze the health condition of human body from biological signals, reduce signal distortion and enhance anti-interference capability, the chip becomes an important design requirement of the chip. Typically, the biosignal collected by the sensor contains a large number of undesired components, while the proportion of the effective biosignal component to the total signal is usually small. Taking the heart rate signal collected by the PPG detection method as an example, the effective component accounts for less than 10% of the total signal amount. Therefore, it is necessary to amplify the extracted bio-signal. Amplifiers with fixed amplification gain may not have a general application range due to the large difference in signal strength among different populations. If the gain is smaller, the sampling circuit is not favorable for accurately acquiring fine biological signal characteristic points; if the gain is too large, saturation distortion may be caused.
Meanwhile, many measurement situations occur when a human body moves, for example, a heart rate value is measured in a running process, if the amplification gain of a signal is larger at the moment, noise in a pass band caused by the movement is saturated, and the phenomenon submerges effective heart rate signal components.
Therefore, in order to adapt to a wider application population and enhance the anti-motion interference capability, a variable gain amplifier circuit needs to be added into the biological signal processing chip.
SUMMERY OF THE UTILITY MODEL
In order to solve at least one of the above problems, a first aspect of the present invention provides a variable gain amplifier, comprising a variable gain amplifying circuit and a detection control circuit, wherein
The variable gain amplifying circuit comprises a first variable gain control unit, a second variable gain control unit and an operational amplifying circuit, and is used for amplifying an input signal and outputting an amplified signal;
the detection control circuit is used for detecting the amplification signal, comparing the peak value of the amplification signal with a preset range, and outputting and adjusting the gain control signals of the first variable gain control unit and the second variable gain control unit so as to adjust the gain of the variable gain amplifier.
Further, the variable gain amplification circuit further comprises a feedback capacitor.
Further, the first variable gain control unit comprises a sampling variable capacitor and four sampling switches;
the second variable gain control unit includes a feedback variable capacitor and four feedback switches.
Further, the clock frequency of the sampling switch and the feedback switch relative to the clock frequency of the input signal satisfies oversampling.
Further, the detection control circuit includes a peak detection circuit and a gain controller, wherein
The peak value detection circuit is used for detecting the amplified signal and outputting the peak value of the amplified signal;
the gain controller is used for comparing the peak value with the preset range and outputting the gain control signal according to the comparison result so as to adjust the gain of the variable gain amplifier.
Further, the gain controller comprises a first comparator, a second comparator and a gating controller, wherein
The first comparator is used for comparing the peak value with a preset first threshold value and outputting a first comparison result;
the second comparator is used for comparing the peak value with a preset second threshold value and outputting a second comparison result;
the gating controller is used for outputting the gain control signal according to the first comparison result and the second comparison result so as to adjust the gain of the variable gain amplifier.
The second aspect of the present invention provides a biological signal processing chip, including the first aspect of the variable gain amplifier.
The utility model has the advantages as follows:
the utility model discloses to present problem, formulate a variable gain amplifier and biological signal processing chip, through variable gain amplifier circuit and detection control circuit effectively improve switched capacitor filter's response speed, the reduction circuit gets into the required time of stable work, can satisfy biological signal processing's requirement.
Drawings
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
FIG. 1 illustrates a negative feedback closed loop variable gain amplifier of the prior art;
FIG. 2 illustrates another negative feedback closed loop variable gain amplifier of the prior art;
fig. 3 shows a block diagram of a variable gain amplifier according to an embodiment of the present invention;
fig. 4 shows a circuit diagram of a variable gain amplifier according to an embodiment of the present invention;
fig. 5 shows a circuit diagram of a variable gain amplifier according to another embodiment of the present invention;
fig. 6 shows the results of a gain linearity test of a variable gain amplifier according to an embodiment of the present invention;
fig. 7 shows a result of a spectrum characteristic test of a variable gain amplifier according to an embodiment of the present invention;
fig. 8 shows a flow chart of a method for using a variable gain amplifier according to an embodiment of the present invention.
Detailed Description
In order to explain the present invention more clearly, the present invention will be further described with reference to the preferred embodiments and the accompanying drawings. Similar parts in the figures are denoted by the same reference numerals. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.
The traditional open-loop gain control amplifier is widely applied to demodulation parts in high-frequency or radio-frequency systems such as wireless receiving, and the like, and the swing amplitude and the distortion degree of the traditional open-loop gain control amplifier cannot meet the requirements of biological signal processing.
In the prior art, a closed loop variable gain amplifier using negative feedback technique is usually adopted, as shown in fig. 1, to use a variable resistor R2A closed loop variable gain amplifier implementing negative feedback, the gain of the amplifier then being:
the gain is related to the resistance values of R1 and R2, and although the operational amplifier can meet the requirements in terms of swing and distortion degree to some extent, the operational amplifier needs strong resistance load capacity, thereby increasing power consumption and area cost. As shown in fig. 2, another closed-loop variable gain amplifier using negative feedback technology, where negative feedback is implemented by connecting variable capacitors C2 and R1 in parallel, the gain of the amplifier is:
the gain is related to the resistance values of C1 and C2, and can meet the requirements in terms of swing amplitude and distortion degree to a certain extent, although the operational amplifier does not require resistance load capacity, the feedback capacitor C does not need resistance load capacity2And a resistance R1The high-pass characteristic is formed to meet the requirement of low biological signalThe frequency requirement requires a larger capacitance resistance value, thereby reducing the precision and increasing the chip cost. Moreover, the closed-loop variable gain amplifier shown in fig. 1 and 2 can only provide a gain greater than 1, and it is difficult to meet the practical application requirements in the bio-signal processing process.
In order to solve the above problem, as shown in fig. 3, an embodiment of the present invention provides a variable gain amplifier, including a variable gain amplifier circuit and a detection control circuit, wherein the variable gain amplifier circuit includes a first variable gain control unit, a second variable gain control unit and an operational amplifier circuit, and is configured to amplify an input signal and output an amplified signal; the detection control circuit is used for detecting the amplification signal, comparing the peak value of the amplification signal with a preset range, and outputting and adjusting the gain control signals of the first variable gain control unit and the second variable gain control unit so as to adjust the gain of the variable gain amplifier.
In a specific example, as shown in fig. 4, the variable gain amplifier includes a variable gain amplification circuit and a detection control circuit, and the input signal is VinThe output signal is VoutWherein the variable gain amplifier circuit adopts switched capacitor technology to adapt to the low frequency characteristic of the biological signal, and inputs the signal VinAmplifying and outputting Vout. In this embodiment, the variable gain amplification circuit includes a first variable gain control unit, a second variable gain control unit, and an operational amplification circuit.
In view of the need to sample the subtle feature points of the bio-signal, in a preferred embodiment, the clock frequencies of the first and second variable gain control units are over-sampled with respect to the clock frequency of the input signal. I.e. at a much higher level than the input signal VinThe frequency more than twice of the bandwidth samples the signal, the quantization noise can be pushed to a higher frequency by oversampling, and aliasing of the sampled signal is avoided by adopting a low-pass filter with a higher cut-off frequency, so that the signal resolution can be effectively improved, and the noise can be reduced.
Specifically, the first embodimentSampling frequency f of variable gain control unit and second variable gain control unitclkAt a frequency of the input signal V in10 times the frequency. The first variable gain control unit comprises a sampling variable capacitor C1And four sampling switches, the sampling variable capacitor C1And the sampling switch forms an in-phase switch capacitor, and the equivalent resistance value of the in-phase switch capacitor is as follows:
similarly, the second variable gain control unit includes a feedback variable capacitor C2 and four feedback switches, the feedback variable capacitor C2 and the feedback switches form an inverting switched capacitor, and then the equivalent resistance of the inverting switched capacitor is:
in view of the fact that the switching capacitor is easy to cause the glitch phenomenon, in a preferred embodiment, the variable gain amplifying circuit further comprises a feedback capacitor. As shown in fig. 4, the feedback capacitor CfIs connected with the reverse-phase switch capacitor in parallel, thereby effectively reducing the burr phenomenon caused by the switch capacitor and leading the output signal VoutAnd if the programmable gain control amplifying circuit is smoother, the transfer equation of the programmable gain control amplifying circuit is as follows:
the low frequency gain of the programmable gain control amplification circuit is:
specifically, the-3 dB bandwidth of the programmable gain control amplifier circuit is:
in this embodiment, the output is detected by a detection control circuitAmplifying the signal VoutDetecting to obtain an amplified signal VoutAnd comparing the gain control signal with a preset range, and outputting a control signal according to a comparison result to adjust the gain control signals of the first variable gain control unit and the second variable gain control unit, so that the gain of the variable gain amplifier is adjusted.
In a preferred embodiment, as shown in fig. 5, the detection control circuit includes a peak detection circuit for detecting the amplified signal and outputting a peak value of the amplified signal, and a gain controller; the gain controller is used for comparing the peak value with the preset range and outputting the gain control signal according to the comparison result so as to adjust the gain of the variable gain amplifier.
Specifically, the peak detection circuit detects the output voltage VoutAnd is compared with a preset desired peak range, which sets an upper high level limit VCHAnd a lower limit V of low levelCLWill output a voltage VoutRespectively pass through the comparator and VCHAnd VCLComparing and obtaining a comparison result Di0And Di1D isi0And Di1And the input signal is input to a gain controller, and a control signal DV is generated by the gain controller to adjust the gain of the variable gain amplification circuit. Specifically, the control signals DV are respectively transmitted to the first variable gain control unit and the second variable gain control unit to adjust the sampling variable capacitor C1And a feedback variable capacitor C2。
In a preferred embodiment, the gain controller includes a first comparator, a second comparator and a gating controller, wherein the first comparator is configured to compare the peak value with a preset first threshold and output a first comparison result; the second comparator is used for comparing the peak value with a preset second threshold value and outputting a second comparison result; the gating controller is used for outputting the gain control signal according to the first comparison result and the second comparison result so as to adjust the gain of the variable gain amplifier.
Namely, the first comparator, the second comparator and the traditional controller are used for realizing the gain control function: the first threshold of the first comparator is VCHWill output a voltage VoutPeak value of and VCHComparing and outputting a first comparison result Di0(ii) a Similarly, the second threshold of the second comparator is VCLWill output a voltage VoutPeak value of and VCLComparing and outputting a first comparison result Di1(ii) a Will Di0And Di1Inputting a gating controller according to Di0And Di1A gain control signal DV is output.
If the output voltage V isoutIs greater than VCHThen generates a control signal DV and controls C1And C2Reducing the gain of the variable gain amplifier according to equation (1) and equation (2); if the peak value of the output voltage Vout is less than VCLThen generates a control signal DV and controls C1And C2Increasing the gain of the variable gain amplifier according to the formula (1) and the formula (2); if the peak value of the output voltage Vout is at VCHAnd VCLAnd keeping the current gain unchanged.
With the variable gain amplifier provided in this embodiment, as shown in fig. 6, the control code on the abscissa corresponds to different capacitance values of the variable capacitor, and the ordinate is the gain, and it can be seen from the figure that when the value of the variable capacitor is different, when the frequency of the input bio-signal is 0.5Hz, the linearity of the gain of the variable gain amplifier reaches 0.9998, which can meet the amplification requirement of the bio-signal. Moreover, as shown in fig. 7, the abscissa is the frequency value of the input biological signal, and the ordinate is the gain, and it can be known from the figure that the gain curve when the variable capacitance takes different values has better spectral characteristics in the low frequency domain, that is, the variable gain amplifier has better spectral characteristics in the low frequency domain, and is suitable for biological signals, and can provide suitable gain for biological signal amplification, reduce signal distortion and enhance anti-interference capability.
Corresponding to the variable gain amplifier provided in the foregoing embodiments, an embodiment of the present application further provides a method for using the variable gain amplifier, and since the method for using the variable gain amplifier provided in the present application corresponds to the variable gain amplifiers provided in the foregoing embodiments, the foregoing embodiments are also applicable to the method for using the variable gain amplifier provided in the present embodiment, and detailed description is omitted in the present embodiment.
As shown in fig. 8, an embodiment of the present application further provides a method of using the variable gain amplifier, including: the variable gain amplifying circuit amplifies an input signal and outputs an amplified signal through a first variable gain control unit, a second variable gain control unit and an operational amplifying circuit; the detection control circuit detects the amplification signal, compares the peak value of the amplification signal with a preset range, and outputs and adjusts the gain control signals of the first variable gain control unit and the second variable gain control unit.
In an alternative embodiment, the first variable gain control unit includes a sampling variable capacitor and four sampling switches, and the second variable gain control unit includes a feedback variable capacitor and four feedback switches; the use method further comprises the following steps: the clock frequency of the sampling switch and the feedback switch relative to the clock frequency of the input signal satisfies oversampling.
In another alternative embodiment, the detection control circuit includes a peak detection circuit and a gain controller; the detecting and controlling circuit detects the amplified signal, compares the peak value of the amplified signal with a preset range, and outputs and adjusts the gain control signals of the first variable gain control unit and the second variable gain control unit, specifically including: the peak detection circuit detects the amplified signal and outputs a peak value of the amplified signal; and the gain controller compares the peak value with the preset range and outputs the gain control signal according to the comparison result.
An embodiment of the present application also provides a biological signal processing chip including the above variable gain amplifier. The health condition of a human body can be analyzed according to the biological signals, signal distortion is reduced, and the anti-interference capability is enhanced.
The utility model discloses to present problem, formulate a variable gain amplifier, application method and biological signal processing chip, through variable gain amplifier circuit and detection control circuit effectively improve switched capacitor filter's response speed, the reduction circuit gets into the required time of stable work, can satisfy biological signal processing's requirement.
Obviously, the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention, and it is obvious for those skilled in the art to make other variations or changes based on the above descriptions, and all the embodiments cannot be exhausted here, and all the obvious variations or changes that belong to the technical solutions of the present invention are still in the protection scope of the present invention.
Claims (7)
1. A variable gain amplifier comprising a variable gain amplification circuit and a detection control circuit, wherein
The variable gain amplifying circuit comprises a first variable gain control unit, a second variable gain control unit and an operational amplifying circuit, and is used for amplifying an input signal and outputting an amplified signal;
the detection control circuit is used for detecting the amplification signal, comparing the peak value of the amplification signal with a preset range, and outputting and adjusting the gain control signals of the first variable gain control unit and the second variable gain control unit so as to adjust the gain of the variable gain amplifier.
2. The variable gain amplifier of claim 1, wherein the variable gain amplification circuit further comprises a feedback capacitor.
3. The variable gain amplifier of claim 1,
the first variable gain control unit comprises a sampling variable capacitor and four sampling switches;
the second variable gain control unit includes a feedback variable capacitor and four feedback switches.
4. The variable gain amplifier of claim 3, wherein the clock frequency of the sampling switch and the feedback switch satisfies oversampling with respect to the clock frequency of the input signal.
5. The variable gain amplifier of claim 1 wherein the detection control circuit comprises a peak detection circuit and a gain controller, wherein
The peak value detection circuit is used for detecting the amplified signal and outputting the peak value of the amplified signal;
the gain controller is used for comparing the peak value with the preset range and outputting the gain control signal according to the comparison result so as to adjust the gain of the variable gain amplifier.
6. The variable gain amplifier of claim 5 wherein the gain controller comprises a first comparator, a second comparator and a gating controller, wherein
The first comparator is used for comparing the peak value with a preset first threshold value and outputting a first comparison result;
the second comparator is used for comparing the peak value with a preset second threshold value and outputting a second comparison result;
the gating controller is used for outputting the gain control signal according to the first comparison result and the second comparison result so as to adjust the gain of the variable gain amplifier.
7. A biological signal processing chip characterized by comprising the variable gain amplifier according to any one of claims 1 to 6.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910469046 | 2019-05-31 | ||
| CN2019104690460 | 2019-05-31 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210168018U true CN210168018U (en) | 2020-03-20 |
Family
ID=68508240
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910660360.7A Pending CN110474612A (en) | 2019-05-31 | 2019-07-22 | A kind of variable gain amplifier, application method and bio signal handle chip |
| CN201921149838.1U Active CN210168018U (en) | 2019-05-31 | 2019-07-22 | Variable gain amplifier and biological signal processing chip |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910660360.7A Pending CN110474612A (en) | 2019-05-31 | 2019-07-22 | A kind of variable gain amplifier, application method and bio signal handle chip |
Country Status (1)
| Country | Link |
|---|---|
| CN (2) | CN110474612A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110474612A (en) * | 2019-05-31 | 2019-11-19 | 华润半导体（深圳）有限公司 | A kind of variable gain amplifier, application method and bio signal handle chip |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1271770B1 (en) * | 2001-06-19 | 2008-08-06 | U-Blox-AG | Analog base band unit for RF receiver and method for using the same |
| JP2005057745A (en) * | 2003-07-22 | 2005-03-03 | Matsushita Electric Ind Co Ltd | High-frequency variable gain amplifier, controller, high-frequency variable gain frequency converter, and communication device |
| US7859355B2 (en) * | 2005-03-24 | 2010-12-28 | Cypress Semiconductor Corporation | Regulated capacitive loading and gain control of a crystal oscillator during startup and steady state operation |
| EP1983320A4 (en) * | 2006-02-07 | 2013-11-27 | Pioneer Corp | Electrostatic capacity detection device |
| JPWO2014080586A1 (en) * | 2012-11-22 | 2017-01-05 | パナソニックＩｐマネジメント株式会社 | Variable gain amplifier and tuner system including the same |
| CN110474612A (en) * | 2019-05-31 | 2019-11-19 | 华润半导体（深圳）有限公司 | A kind of variable gain amplifier, application method and bio signal handle chip |
-
2019
- 2019-07-22 CN CN201910660360.7A patent/CN110474612A/en active Pending
- 2019-07-22 CN CN201921149838.1U patent/CN210168018U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110474612A (en) * | 2019-05-31 | 2019-11-19 | 华润半导体（深圳）有限公司 | A kind of variable gain amplifier, application method and bio signal handle chip |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110474612A (en) | 2019-11-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9722563B2 (en) | System and method for high input capacitive signal amplifier | |
| US8755868B2 (en) | Adaptive sampling | |
| CN106943138A (en) | Signal conditioner, ECG detection device and signal condition method | |
| CN111238632B (en) | High-precision vibration signal acquisition and processing system | |
| CN210168018U (en) | Variable gain amplifier and biological signal processing chip | |
| CN104950165A (en) | Detecting circuit and detecting method | |
| US11914092B2 (en) | Inductive magnetic sensor and electromagnetic prospecting equipment | |
| CN203416227U (en) | Small signal amplification circuit | |
| CN201956980U (en) | Automatic gain adjusting circuit in high dynamic range | |
| CN109521833B (en) | Broadband signal conditioning device for arbitrary waveform generator | |
| CN204807622U (en) | Detection circuitry | |
| CN103338028B (en) | Triple oscillatory feedback Weak Signal Processing circuit | |
| CN204089737U (en) | Realize the high-precision amplifying structure of variable gain | |
| CN207664957U (en) | A kind of multistage highly-precise filtering circuit based on programmable filter LTC1063 and active filter | |
| CN202634368U (en) | Intelligent section-type amplifying circuit | |
| CN102255608A (en) | Automatic gain regulating circuit with large dynamic range | |
| CN108008205B (en) | Self-adaptive signal conditioning circuit and method for electromagnetic field detection | |
| CN207281634U (en) | A kind of signal processing circuit for being used for ns grades of laser pulses | |
| CN207798272U (en) | A kind of APD noise suppression circuits | |
| CN206620106U (en) | A kind of power control circuit | |
| CN108988886B (en) | Low-cost three-branch millimeter wave alarm receiving circuit | |
| CN220307190U (en) | Signal filter circuit | |
| CN218037249U (en) | Detection circuit for switching power supply | |
| CN110638443A (en) | Electrocardiosignal reading circuit | |
| CN205883177U (en) | Digifax combines AGC circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20210812 Address after: No.180-6, Linghu Avenue, Taihu International Science and Technology Park, Xinwu District, Wuxi City, Jiangsu Province, 214135 Patentee after: China Resources micro integrated circuit (Wuxi) Co., Ltd Address before: Part 8a, Tianxiang building, Tian'an Digital City, chegongmiao, Shennan West Road, Futian District, Shenzhen City, Guangdong Province Patentee before: CHINA RESOURCES SEMICONDUCTOR (SHENZHEN) Co.,Ltd. |