CN105450211A - Signal detection circuit - Google Patents
Signal detection circuit Download PDFInfo
- Publication number
- CN105450211A CN105450211A CN201410247906.3A CN201410247906A CN105450211A CN 105450211 A CN105450211 A CN 105450211A CN 201410247906 A CN201410247906 A CN 201410247906A CN 105450211 A CN105450211 A CN 105450211A
- Authority
- CN
- China
- Prior art keywords
- signal
- voltage threshold
- output
- comparator
- level
- 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.)
- Pending
Links
Landscapes
- Amplifiers (AREA)
Abstract
The invention provides a signal detection circuit, and the circuit comprises a bandpass filter amplifier, a double-point comparison integrator, and a hysteresis comparator. The bandpass filter amplifier is used for carrying out the bandpass filtering and amplification of a detected signal received by a receiving end. The double-point comparison integrator comprises an integration capacitor, and is used for comparing an amplification signal received by an input end of the double-point comparison integrator with a first voltage threshold value and a second voltage threshold value, so as to obtain and output a comparison integration signal. The hysteresis comparator is used for carrying out the hysteresis comparison of the comparison integration signal received by an input end of the hysteresis comparator, and outputting a discrimination signal through an output end of the hysteresis comparator. When the comparison integration signal is less than a first comparison level, the discrimination signal is converted into a first level signal from a second level signal. When the comparison integration signal is greater than the second level signal, the discrimination signal is converted into the second level signal from the first level signal. Compared with the prior art, the circuit is strong in anti-interference capability, and is high in detection sensitivity.
Description
[technical field]
The present invention relates to circuit design field, particularly a kind of signal deteching circuit.
[background technology]
Signal deteching circuit is a kind of functional unit often used in control circui design, and it exports decision signal after detecting the size of detected signal, and this decision signal is using the control enable signal as other functional unit.Please refer to shown in Fig. 1, it is the circuit diagram of a kind of signal deteching circuit of the prior art.This signal deteching circuit comprises amplifier 110, single-point compares integrator 120 and compare to determine loop 130, its specific works process is: first detected signal VIN enters amplifier 110 and amplify, enter single-point subsequently to compare integrator 120 and do amplitude detection and integration, now, the output that described single-point compares integrator 120 is a DC level, compare with the DC level preset and export comparative result after this DC level enters and compares to determine loop 130, namely exporting decision signal VO.
In prior art, the amplifier more than 110 in signal deteching circuit adopts the amplifier framework of fixed gain, causes its background noise rejection ability weak; Single-point compares integrator 120 and adopts single-point comparative structure, and it can only detection signal forward amplitude, therefore, signal determining can be caused not accurate enough; Compare to determine loop employing more than 130 and simply compare to determine logic, namely when comparing to determine DC level that loop 130 receives and being less than the DC level preset, its decision signal VO exported is the first level signal, when comparing to determine DC level that loop 130 receives and being greater than the DC level preset, its decision signal VO saltus step exported is second electrical level signal, thisly simply compares to determine the decision signal VO that logic makes it export and is easily disturbed.
Therefore, be necessary to provide a kind of technical scheme of improvement to overcome the problems referred to above.
[summary of the invention]
The object of the present invention is to provide a kind of signal deteching circuit, its antijamming capability is strong, and detection sensitivity is high.
In order to solve the problem, the invention provides a kind of signal deteching circuit, it comprise band-pass filter amplifier, two point compares integrator and hysteresis comparator.The detected signal that described band-pass filter amplifier is used for its input to receive carries out bandpass filtering and amplifies, and exports amplifying signal by its output, described two point compares integrator and comprises integrating capacitor, it compares for the amplifying signal that received by its input and the first voltage threshold and the second voltage threshold, when the instant electric potential of described amplifying signal charges higher than the first voltage threshold or lower than during the second voltage threshold to described integrating capacitor, otherwise, described integrating capacitor is discharged, integrated signal is compared to obtain and to export, wherein the first voltage threshold is higher than the second voltage threshold: described hysteresis comparator is used for carrying out sluggishness to the comparison integrated signal that its input receives and compares, and export decision signal by its output, described compare integrated signal be less than the first comparative level time, it is the first level signal that described decision signal is overturn by second electrical level signal, described compare integrated signal be greater than the second comparative level time, it is second electrical level signal that described decision signal is overturn by the first level signal, wherein the first comparative level is less than the second comparative level.
Further, described band-pass filter amplifier comprises the first electric capacity, the second electric capacity, the first resistance, the second resistance and operational amplifier, between the input that the first electric capacity and the second electric capacity are connected to described band-pass filter amplifier successively and output; First resistance and the second resistance are series between the output and ground of described band-pass filter amplifier successively; The normal phase input end of described operational amplifier is connected with the connected node between the first resistance and the second resistance, and its negative-phase input is connected with the connected node between the first electric capacity and the second electric capacity, and its output is connected with the output of described band-pass filter amplifier.
Further, described two point compares integrator and also comprises and compare control unit, the first current source and the second current source, and described first current source and the second current source are connected between power supply and earth terminal successively, described integrating capacitor is connected between connected node between the first current source and the second current source and earth terminal, the output that connected node between described first current source and the second current source and described two point compare integrator is connected, the sense of current of described first current source and the second current source all flows to earth terminal, the described input comparing control unit is connected to receive amplifying signal with the input that described two point compares integrator, its first output is connected with the control end of described first current source, its second output is connected with the control end of described second current source, the described control unit that compares compares with described first voltage threshold and the second voltage threshold respectively for the amplifying signal received, when the instant electric potential of amplifying signal is greater than the first voltage threshold or is less than the second voltage threshold, the described control unit that compares controls the first current source to the 3rd capacitor charging, otherwise the described control unit that compares controls the second current source to the 3rd capacitor discharge.
Further, DC level < first voltage threshold of the second voltage threshold < amplifying signal.
Further, the mean value of described first voltage threshold and the second voltage threshold is mid-point voltage, and this mid-point voltage equals the DC level of amplifying signal, and the input current potential of described band-pass filter amplifier and output potential are set to the supply voltage of 1/2 times.
Further, described two point compares integrator and also comprises voltage threshold and produce circuit, described voltage threshold produce circuit for generation of and export described first voltage threshold and the second voltage threshold.
Further, described voltage threshold produces circuit and comprises the 3rd resistance, the 4th resistance, the 5th resistance and the 6th resistance that are series at successively between internal reference voltage and earth terminal, the voltage that connected node between 3rd resistance and the 4th resistance exports is described first voltage threshold, the voltage that connected node between 5th resistance and the 6th resistance exports is described second voltage threshold, and the voltage of the connected node between the 4th resistance and the 5th resistance is mid-point voltage.
Further, the described control unit that compares comprises the first comparator, second comparator, or door and the first inverter, the input that the normal phase input end of the first comparator all compares integrator with described two point with the negative-phase input of the second comparator is connected, the negative-phase input of the first comparator is connected with the first voltage threshold, the normal phase input end of the second comparator is connected with the second voltage threshold, the output of the first comparator and the output of the second comparator respectively with or two inputs of door be connected, or the output of door is connected with described the first output comparing control unit, the input of the first inverter with or the output of door be connected, the output of the first inverter is connected with described the second output comparing control unit.
Further, described hysteresis comparator comprises the 3rd comparator and the second inverter, the negative-phase input of described 3rd comparator is connected with the input of described hysteresis comparator to receive and describedly compares integrated signal, its normal phase input end selects described first comparative level of a connection and the second comparative level, its output is connected with the input of described second inverter, and the output of the second inverter is connected with the output of described hysteresis comparator.
Further, time initial, the normal phase input end of described 3rd comparator is connected with the second comparative level, and when comparing integrated signal lower than the second comparative level, the decision signal that the second inverter exports is low level; When comparing integrated signal and rise and being greater than the second comparative level, the decision signal that second inverter exports is high level, and the normal phase input end of the 3rd comparator switches to and is connected with described first comparative level, when the normal phase input end of the 3rd comparator switch to be connected with described first comparative level time, if when the first comparative level < compares integrated signal < the second comparative level, the decision signal that the second inverter exports still maintains high level; Only when comparing integrated signal lower than the first comparative level, the decision signal output low level that the second inverter exports, and the normal phase input end of the 3rd comparator is connected with the second comparative level.
Compared with prior art, signal deteching circuit in the present invention is provided with band-pass filter amplifier, two point compares integrator and hysteresis comparator, because its setting to each circuit module is optimized, this improves antijamming capability and the detection sensitivity of signal deteching circuit.
[accompanying drawing explanation]
In order to be illustrated more clearly in the technical scheme of the embodiment of the present invention, below the accompanying drawing used required in describing embodiment is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.Wherein:
Fig. 1 is the circuit diagram of a kind of signal deteching circuit of the prior art;
Fig. 2 is the circuit diagram of the present invention's signal deteching circuit in one embodiment;
Fig. 3 is the band-pass filter amplifier circuit diagram in one embodiment in the present invention;
Fig. 4 is the amplification in one embodiment of band-pass filter amplifier in Fig. 3 and bandpass characteristics simulation waveform figure;
Fig. 5 is that the two point in the present invention compares integrator circuit diagram in one embodiment;
Fig. 6 be the present invention in one embodiment two point compare the oscillogram of the amplifying signal that integrator receives;
Fig. 7 is the hysteresis comparator circuit diagram in one embodiment in the present invention.
[embodiment]
For enabling above-mentioned purpose of the present invention, feature and advantage become apparent more, and below in conjunction with the drawings and specific embodiments, the present invention is further detailed explanation.
Alleged herein " embodiment " or " embodiment " refers to special characteristic, structure or the characteristic that can be contained at least one implementation of the present invention.Different local in this manual " in one embodiment " occurred not all refers to same embodiment, neither be independent or optionally mutually exclusive with other embodiments embodiment.Unless stated otherwise, connection herein, be connected, word that the expression that connects is electrically connected all represents and is directly or indirectly electrical connected.
Please refer to shown in Fig. 2, it is the circuit diagram of the present invention's signal deteching circuit in one embodiment, and described signal deteching circuit comprises band-pass filter amplifier 210, two point compares integrator 220 and hysteresis comparator 230.The input of described band-pass filter amplifier 210 receives detected signal Vin as the input of described signal deteching circuit, described band-pass filter amplifier 210 carries out bandpass filtering for the detected signal Vin received by its input and amplifies, and exports amplifying signal Vo1 (i.e. filtering detected signal Vin after amplification) by its output; The input that described two point compares integrator 220 is connected with the output of described band-pass filter amplifier 210, described two point compares integrator 220 and carries out for the amplifying signal Vo1 received its input positive and negative to amplitude detection and integration, and is exported by its output and compare integrated signal Vo2; The output that input and the described two point of described hysteresis comparator 230 compare integrator 220 is connected, its output is as the output of described signal deteching circuit, described hysteresis comparator 230 carries out sluggishness for the comparison integrated signal Vo2 received its input and compares to determine, and exporting decision signal Vout by its output, this decision signal Vout represents whether the amplitude of detected signal Vin exceeds predetermined threshold range.
Particular circuit configurations and the operation principle of each functional module in Fig. 2 is specifically introduced below in conjunction with accompanying drawing 3-7.For the ease of representing input and the output of each functional module, received the label of signal as the input of its correspondence of (or input) below by each input, the signal exported by each output is as the label of the output of its correspondence.
Please refer to shown in Fig. 3, it is the band-pass filter amplifier circuit diagram in one embodiment in Fig. 2.Described band-pass filter amplifier comprises the first electric capacity C1, the second electric capacity C2, the first resistance Rf, the second resistance R and operational amplifier unit OA, wherein, the first electric capacity C1 and the second electric capacity C2 is connected between the input Vin of described band-pass filter amplifier and output end vo 1 successively; First resistance Rf and the second resistance R is series between the output end vo 1 of described band-pass filter amplifier and earth terminal GND successively; The normal phase input end "+" of described operational amplifier unit OA is connected with the connected node A between the first resistance Rf and the second resistance R, its negative-phase input "-" is connected with the connected node B between the first electric capacity C1 and the second electric capacity C2, and its output is connected with the output end vo 1 of described band-pass filter amplifier.Wherein, the first electric capacity C1, the second electric capacity C2 and associated impedances form a simple first-order bandpass filter amplifier, the filter center frequency f0 of this band-pass filter amplifier can by adjusting the first electric capacity C1, the capacitance of the second electric capacity C2 mates.
In an embodiment of Fig. 3, Rf/R=5.6 is set, C1=9pF, C2=1pF, wherein, Rf and R is respectively the resistance value of the first resistance Rf and the second resistance R, C1 and C2 is respectively the capacitance of the first electric capacity C1 and the second electric capacity C2, the gain amplifier Gv=15dB of this band-pass filter amplifier can be obtained, filter center frequency f0=25kHz, filtering bandwidth BW=50kHz, the amplification of corresponding band-pass filter amplifier and bandpass characteristics simulation waveform figure are as shown in Figure 4, abscissa in this diagram is HZ (hertz), and ordinate is V (voltage).
In summary, band-pass filter amplifier of the present invention can carry out bandpass filtering to described detected signal Vin and amplify, thus effective Background suppression noise, in addition, when detected signal Vin is less, the gain G v by promoting this band-pass filter amplifier carrys out the sensitivity of elevator belt bandpass filter amplifier.
In other embodiments, described band-pass filter amplifier also can adopt band-pass filter amplifier of the prior art, so place repeats no more.
Please refer to shown in Fig. 5, it is that two point in Fig. 2 compares integrator circuit diagram in one embodiment.Described two point compares integrator and comprises integrating capacitor C3, it compares with the first voltage threshold VH pre-set and the second voltage threshold VL for the amplifying signal Vo1 received by its input, when the instant electric potential of described amplifying signal Vo1 charges higher than the first voltage threshold VH or lower than during the second voltage threshold VL to described integrating capacitor C3, otherwise, to described integrating capacitor C3 electric discharge, integrated signal Vo2 is compared to obtain and to export, this compares the intensity that integrated signal Vo2 characterizes amplifying signal Vo1, wherein, the first voltage threshold VH is higher than the second voltage threshold VL.
Two point in Fig. 5 compares integrator and also comprises and compare control unit 510, first current source I1 and the second current source I2.
Described first current source I1 and the second current source I2 is connected between power supply VCC and earth terminal GND successively; Described integrating capacitor C3 is connected between connected node C between the first current source I1 and the second current source I2 and earth terminal GND; Connected node C between described first current source I1 and the second current source I2 is connected with the output that described two point compares integrator, and the sense of current of described first current source I1 and the second current source I2 all flows to earth terminal GND.
The described input comparing control unit 510 is connected to receive amplifying signal Vo1 with the input that described two point compares integrator, its first output 1 is connected with the control end of described first current source I1, and its second output 2 is connected with the control end of described second current source I2.The described control unit 510 that compares compares with described first voltage threshold VH and the second voltage threshold VL respectively for the amplifying signal Vo1 received, positive and negative to amplitude detection to carry out amplifying signal Vo1.When the instant electric potential of amplifying signal Vo1 is greater than the first voltage threshold VH or is less than the second voltage threshold VL, the described control unit 510 that compares controls the first current source I1 and charges to integrating capacitor C3; When the instant electric potential of amplifying signal Vo1 is greater than the second voltage threshold VL and is less than the first voltage threshold VH, the described control unit 510 that compares controls the second current source I2 and discharges to integrating capacitor C3.
In order to make describedly to compare the positive and negative more accurate to amplitude detection of control unit 510 couples of amplifying signal Vo1, the DC level < first voltage threshold VH of the second voltage threshold VL < amplifying signal Vo1 need be set; The supply voltage that the input current potential of described band-pass filter amplifier 210 and output potential equal 1/2 times is set.
In the embodiment shown in fig. 5, the described control unit 510 that compares comprises the first comparator comp1, second comparator comp2, or door OR and the first inverter INV1, the input Vo1 that wherein normal phase input end of the first comparator comp1 and the negative-phase input of the second comparator comp2 all compare integrator with described two point is connected, the negative-phase input of the first comparator comp1 is connected with the first voltage threshold VH, the normal phase input end of the second comparator comp2 is connected with the second voltage threshold VL, the output of the first comparator comp1 and the output of the second comparator comp2 respectively with or two inputs of door OR be connected, or the output of door OR is connected with described the first output 1 comparing control unit 510, the input of the first inverter INV1 with or the output of door OR be connected, the output of the first inverter INV1 is connected with described the second output 2 comparing control unit 510.This specific works process comparing control unit 510 is: when the instant electric potential of amplifying signal Vo1 is greater than the first voltage threshold VH, first comparator comp1 exports high level, second comparator comp2 output low level, or door OR output high level controls the first current source I1 conducting, to charge to integrating capacitor C3, the first inverter INV1 output low level controls the second current source I2 and turns off; When the instant electric potential of amplifying signal Vo1 is less than the first voltage threshold VH and is greater than the second voltage threshold VL, described first comparator comp1 output low level, second comparator comp2 output low level, or door OR output low level controls the first current source I1 and turns off, first inverter INV1 exports high level and controls the second current source I2 conducting, to discharge to integrating capacitor C3; When the instant electric potential of amplifying signal Vo1 is less than the second voltage threshold VL, described first comparator comp1 output low level, second comparator comp2 exports high level, or door OR output high level controls the first current source I1 conducting, to charge to integrating capacitor C3, the first inverter INV1 output low level controls the second current source I2 and turns off.
In other embodiments, the normal phase input end of the first comparator comp1 and the annexation of negative-phase input can be exchanged, namely the normal phase input end of the first comparator comp1 is connected with the first voltage threshold VH, and the input Vo1 that negative-phase input and described two point compare integrator is connected; Or/and exchange the normal phase input end of the second comparator comp2 and the annexation of negative-phase input, namely the negative-phase input of the second comparator comp2 is connected with the second voltage threshold VL, the input Vo1 that its normal phase input end and described two point compare integrator is connected, corresponding amendment first comparator comp1 and the latter linked logical circuit of the second comparator comp2, as long as when the instant electric potential of amplifying signal Vo1 is greater than the first voltage threshold VH or is less than the second voltage threshold VL, the described control unit 510 that compares controls the first current source I1 and charges to integrating capacitor C3; When the instant electric potential of amplifying signal Vo1 is greater than the second voltage threshold VL and is less than the first voltage threshold VH, the described control unit 510 that compares controls the second current source I2 and discharges to integrating capacitor C3.
In the embodiment shown in fig. 5, described two point compares integrator and also comprises voltage threshold and produce circuit 520, described voltage threshold produce circuit 520 for generation of and export described first voltage threshold VH and the second voltage threshold VL.Concrete, described voltage threshold produces circuit 520 and comprises the 3rd resistance R1 be series at successively between internal reference voltage Vreg and earth terminal GND, 4th resistance R2, 5th resistance R3 and the 6th resistance R4, wherein, the voltage that connected node between 3rd resistance R1 and the 4th resistance R2 exports is described first voltage threshold VH, the voltage that connected node between 5th resistance R3 and the 6th resistance R4 exports is described second voltage threshold VL, connected node voltage between 4th resistance R2 and the 5th resistance R3 is mid-point voltage VM, this mid-point voltage VM is mean value (the i.e. VH=VM+ △ V of the first voltage threshold VH and the second voltage threshold VL, VL=VM-△ V, or VM=(VH+VL)/2), preferably, this mid-point voltage VM equals the DC level of the amplifying signal Vo1 that described band-pass filter amplifier exports, and like this, the described control unit 510 that compares can be made to detect the positive and negative to amplitude of amplifying signal Vo1 more accurately.
Please refer to shown in Fig. 6, it is in one embodiment, and two point compares the oscillogram of the amplifying signal Vo1 that integrator receives.In this embodiment, described amplifying signal Vo1 is sinusoidal signal, in one-period, only when time period t 2-t3, t4-t5, first current source I1 charges to integrating capacitor C3, be that the second current source I2 discharges to the 3rd electric capacity C3 At All Other Times, like this, the comparison integrated signal Vo2 that two point compares integrator output is:
In summary, the two point in the present invention compares integrator 220 can detect the positive and negative to amplitude of amplifying signal Vo1 simultaneously, thus avoids the detection mistake because negative-going signal amplitude causes greatly.
Please refer to shown in Fig. 7, it is the hysteresis comparator circuit diagram in one embodiment in Fig. 2.Be previously provided with the first comparative level Va and the second comparative level Vb in described hysteresis comparator, wherein, the first comparative level Va is less than the second comparative level Vb.Described hysteresis comparator is used for carrying out sluggishness to the comparison integrated signal Vo2 that its input receives and compares, and export decision signal Vout by its output, described compare integrated signal Vo2 be less than the first comparative level Va time, it is the first level signal that described decision signal Vout is overturn by second electrical level signal, described compare integrated signal Vo2 be greater than the second comparative level Vb time, described decision signal Vout by first level signal overturn be second electrical level signal.
In the embodiment shown in fig. 7, described hysteresis comparator comprises the 3rd comparator comp3 and the second inverter INV2, the negative-phase input of described 3rd comparator comp3 is connected with the input of described hysteresis comparator to receive and describedly compares integrated signal Vo2, its normal phase input end selects a connection described first comparative level Va and the second comparative level Vb, its output is connected with the input of described second inverter INV2, and the output of the second inverter INV2 is connected with the output end vo ut of described hysteresis comparator.The operation principle of described hysteresis comparator is: time initial, the normal phase input end arranging the 3rd comparator comp3 is connected (namely the initial value of the built-in comparative level of described hysteresis comparator is set to higher level Vb) with the second comparative level Vb, when comparing integrated signal Vo2 lower than the second comparative level Vb, the decision signal Vout that second inverter INV2 exports is low level (it is the first level signal), when comparing integrated signal Vo2 and rise and being greater than the second comparative level Vb, the decision signal Vout that second inverter INV2 exports is that (it is second electrical level signal to high level, sign has signal), simultaneously, the normal phase input end of the 3rd comparator comp3 switches to and is connected (namely the built-in comparative level of described hysteresis comparator is set to comparatively low level Va) with described first comparative level Va, subsequently, if when the first comparative level Va< compares integrated signal Vo2< second comparative level Vb, the decision signal Vout that the second inverter INV2 exports still maintains high level, only when comparing integrated signal Vo2 lower than the first comparative level Va, the decision signal Vout that second inverter INV2 exports is just low level, and the normal phase input end of the 3rd comparator comp3 switches to be connected with the second comparative level Vb (namely the built-in comparative level of described hysteresis comparator is set to higher level Vb) simultaneously.Like this, when the comparison integrated signal Vo2 that described hysteresis comparator receives grows out of nothing, arrange a higher comparison threshold, the decision signal Vout of output just effectively, prevents other interference from causing misoperation when ensureing that signal is good; And once signal detected, a lower comparison threshold is then set, ensure the continuation of input, the decision signal Vout simultaneously preventing it from exporting is owing to disturbing the frequent switching caused, even if thus guarantee disturbs (with signal same frequency), described hysteresis comparator also can maintain accurate judgement.
In other embodiments, the normal phase input end of the 3rd comparator comp3 and the annexation of negative-phase input can be exchanged, namely the normal phase input end of described 3rd comparator comp3 receives as the input of described hysteresis comparator and describedly compares integrated signal Vo2, its negative-phase input selects a connection described first comparative level Va and the second comparative level Vb, the latter linked logical circuit of corresponding amendment the 3rd comparator comp3; Or described hysteresis comparator 230 also can adopt hysteresis comparator of the prior art, as long as when the comparison integral level Vo2 that described hysteresis comparator receives is less than described first comparative level Va, it is the first level signal that the decision signal Vout that its output exports is overturn by second electrical level signal; When the comparison integral level Vo2 that described hysteresis comparator receives is greater than described second comparative level Vb, it is second electrical level signal that the decision signal Vout that its output exports is overturn by the first level signal.
In summary, signal deteching circuit in the present invention is provided with band-pass filter amplifier 210, two point compares integrator 220 and hysteresis comparator 230, compared with prior art, it is optimized the setting of each circuit module, this improves antijamming capability and the detection sensitivity of signal deteching circuit.
It is pointed out that the scope be familiar with person skilled in art and any change that the specific embodiment of the present invention is done all do not departed to claims of the present invention.Correspondingly, the scope of claim of the present invention is also not limited only to previous embodiment.
Claims (10)
1. a signal deteching circuit, is characterized in that, it comprises band-pass filter amplifier, two point compares integrator and hysteresis comparator,
The detected signal that described band-pass filter amplifier is used for its input to receive carries out bandpass filtering and amplifies, and exports amplifying signal by its output;
Described two point compares integrator and comprises integrating capacitor, it compares for the amplifying signal that received by its input and the first voltage threshold and the second voltage threshold, when the instant electric potential of described amplifying signal charges higher than the first voltage threshold or lower than during the second voltage threshold to described integrating capacitor, otherwise, described integrating capacitor is discharged, compare integrated signal to obtain and to export, wherein the first voltage threshold is higher than the second voltage threshold:
Described hysteresis comparator is used for carrying out sluggishness to the comparison integrated signal that its input receives and compares, and export decision signal by its output, described compare integrated signal be less than the first comparative level time, it is the first level signal that described decision signal is overturn by second electrical level signal, described compare integrated signal be greater than the second comparative level time, it is second electrical level signal that described decision signal is overturn by the first level signal, and wherein the first comparative level is less than the second comparative level.
2. signal deteching circuit according to claim 1, is characterized in that, described band-pass filter amplifier comprises the first electric capacity, the second electric capacity, the first resistance, the second resistance and operational amplifier,
Between the input that first electric capacity and the second electric capacity are connected to described band-pass filter amplifier successively and output; First resistance and the second resistance are series between the output and ground of described band-pass filter amplifier successively; The normal phase input end of described operational amplifier is connected with the connected node between the first resistance and the second resistance, and its negative-phase input is connected with the connected node between the first electric capacity and the second electric capacity, and its output is connected with the output of described band-pass filter amplifier.
3. signal deteching circuit according to claim 1, is characterized in that, described two point compares integrator and also comprises and compare control unit, the first current source and the second current source,
Described first current source and the second current source are connected between power supply and earth terminal successively; Described integrating capacitor is connected between connected node between the first current source and the second current source and earth terminal; The output that connected node between described first current source and the second current source and described two point compare integrator is connected, and the sense of current of described first current source and the second current source all flows to earth terminal,
The described input comparing control unit is connected to receive amplifying signal with the input that described two point compares integrator, its first output is connected with the control end of described first current source, its second output is connected with the control end of described second current source, the described control unit that compares compares with described first voltage threshold and the second voltage threshold respectively for the amplifying signal received, when the instant electric potential of amplifying signal is greater than the first voltage threshold or is less than the second voltage threshold, the described control unit that compares controls the first current source to the 3rd capacitor charging; Otherwise the described control unit that compares controls the second current source to the 3rd capacitor discharge.
4. signal deteching circuit according to claim 3, is characterized in that,
DC level < first voltage threshold of the second voltage threshold < amplifying signal.
5. signal deteching circuit according to claim 4, it is characterized in that, the mean value of described first voltage threshold and the second voltage threshold is mid-point voltage, this mid-point voltage equals the DC level of amplifying signal, and the input current potential of described band-pass filter amplifier and output potential are set to the supply voltage of 1/2 times.
6. signal deteching circuit according to claim 4, is characterized in that, described two point compares integrator and also comprises voltage threshold and produce circuit, described voltage threshold produce circuit for generation of and export described first voltage threshold and the second voltage threshold.
7. signal deteching circuit according to claim 6, is characterized in that, described voltage threshold produces circuit and comprises the 3rd resistance, the 4th resistance, the 5th resistance and the 6th resistance that are series at successively between internal reference voltage and earth terminal,
The voltage that connected node between 3rd resistance and the 4th resistance exports is described first voltage threshold, the voltage that connected node between 5th resistance and the 6th resistance exports is described second voltage threshold, and the voltage of the connected node between the 4th resistance and the 5th resistance is mid-point voltage.
8. signal deteching circuit according to claim 3, is characterized in that,
The described control unit that compares comprises the first comparator, the second comparator or door and the first inverter,
The input that the normal phase input end of the first comparator all compares integrator with described two point with the negative-phase input of the second comparator is connected, the negative-phase input of the first comparator is connected with the first voltage threshold, the normal phase input end of the second comparator is connected with the second voltage threshold, the output of the first comparator and the output of the second comparator respectively with or two inputs of door be connected, or the output of door is connected with described the first output comparing control unit, the input of the first inverter with or the output of door be connected, the output of the first inverter is connected with described the second output comparing control unit.
9. signal deteching circuit according to claim 3, is characterized in that, described hysteresis comparator comprises the 3rd comparator and the second inverter,
The negative-phase input of described 3rd comparator is connected with the input of described hysteresis comparator to receive and describedly compares integrated signal, its normal phase input end selects described first comparative level of a connection and the second comparative level, its output is connected with the input of described second inverter, and the output of the second inverter is connected with the output of described hysteresis comparator.
10. signal deteching circuit according to claim 9, is characterized in that,
Time initial, the normal phase input end of described 3rd comparator is connected with the second comparative level, and when comparing integrated signal lower than the second comparative level, the decision signal that the second inverter exports is low level; When comparing integrated signal and rise and being greater than the second comparative level, the decision signal that the second inverter exports is high level, and the normal phase input end of the 3rd comparator switches to and is connected with described first comparative level,
When the normal phase input end of the 3rd comparator switch to be connected with described first comparative level time, if when the first comparative level < compares integrated signal < the second comparative level, the decision signal that the second inverter exports still maintains high level; Only when comparing integrated signal lower than the first comparative level, the decision signal output low level that the second inverter exports, and the normal phase input end of the 3rd comparator is connected with the second comparative level.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410247906.3A CN105450211A (en) | 2014-06-05 | 2014-06-05 | Signal detection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410247906.3A CN105450211A (en) | 2014-06-05 | 2014-06-05 | Signal detection circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105450211A true CN105450211A (en) | 2016-03-30 |
Family
ID=55560072
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410247906.3A Pending CN105450211A (en) | 2014-06-05 | 2014-06-05 | Signal detection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105450211A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106301346A (en) * | 2016-08-08 | 2017-01-04 | 成都华微电子科技有限公司 | There is the receptor control method of stable input trigging signal |
| CN106301345A (en) * | 2016-08-08 | 2017-01-04 | 成都华微电子科技有限公司 | Supply voltage adjusts the receptor stably inputting trigging signal |
| CN109100564A (en) * | 2017-06-21 | 2018-12-28 | 浙江大华技术股份有限公司 | A kind of signal fluctuation detection circuit |
| CN109347481A (en) * | 2018-09-17 | 2019-02-15 | 南京中感微电子有限公司 | A kind of continuous time plural number band logical sigma-delta analog-digital converter and Bluetooth RF transceiver |
| CN109357783A (en) * | 2018-12-21 | 2019-02-19 | 广州市优仪电子科技有限公司 | Temperature sensing circuit |
| CN111257673A (en) * | 2020-02-17 | 2020-06-09 | 广东博智林机器人有限公司 | Capacitor fault detection circuit, detection method and servo drive circuit |
| US11196408B2 (en) | 2017-06-21 | 2021-12-07 | Zhejiang Dahua Technology Co., Ltd. | System and method for mixed transmission of signals and power supply through a single cable |
| CN114112169A (en) * | 2020-08-28 | 2022-03-01 | 深圳市帝迈生物技术有限公司 | Pressure detection circuit and blood analysis device |
| CN114326916A (en) * | 2022-01-04 | 2022-04-12 | 上海南芯半导体科技股份有限公司 | Reference voltage detection circuit |
| CN115407180A (en) * | 2022-11-02 | 2022-11-29 | 上海阿米芯光半导体有限责任公司 | Signal intensity detection circuit with adjustable threshold value, threshold voltage adjusting method and hysteresis adjusting method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2064033U (en) * | 1989-09-06 | 1990-10-17 | 胡执冲 | Digital electronic temperature controlling protector of refrigerator |
| US5649249A (en) * | 1992-07-31 | 1997-07-15 | Fuji Photo Film Co., Ltd. | Camera with exposed frame detector |
| JPH10164385A (en) * | 1996-11-29 | 1998-06-19 | Sanyo Electric Co Ltd | Vertical output circuit |
| CN101221068A (en) * | 2008-01-23 | 2008-07-16 | 友达光电股份有限公司 | Environment optical detection system and method |
| CN102288854A (en) * | 2011-05-10 | 2011-12-21 | 山东鲁亿通智能电气股份有限公司 | Switchgear fault current collection device |
| CN103499248A (en) * | 2013-09-11 | 2014-01-08 | 中国船舶重工集团公司第七一〇研究所 | High-speed rotating projectile rotation number counting circuit |
-
2014
- 2014-06-05 CN CN201410247906.3A patent/CN105450211A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2064033U (en) * | 1989-09-06 | 1990-10-17 | 胡执冲 | Digital electronic temperature controlling protector of refrigerator |
| US5649249A (en) * | 1992-07-31 | 1997-07-15 | Fuji Photo Film Co., Ltd. | Camera with exposed frame detector |
| JPH10164385A (en) * | 1996-11-29 | 1998-06-19 | Sanyo Electric Co Ltd | Vertical output circuit |
| CN101221068A (en) * | 2008-01-23 | 2008-07-16 | 友达光电股份有限公司 | Environment optical detection system and method |
| CN102288854A (en) * | 2011-05-10 | 2011-12-21 | 山东鲁亿通智能电气股份有限公司 | Switchgear fault current collection device |
| CN103499248A (en) * | 2013-09-11 | 2014-01-08 | 中国船舶重工集团公司第七一〇研究所 | High-speed rotating projectile rotation number counting circuit |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106301346A (en) * | 2016-08-08 | 2017-01-04 | 成都华微电子科技有限公司 | There is the receptor control method of stable input trigging signal |
| CN106301345A (en) * | 2016-08-08 | 2017-01-04 | 成都华微电子科技有限公司 | Supply voltage adjusts the receptor stably inputting trigging signal |
| CN106301346B (en) * | 2016-08-08 | 2019-07-05 | 成都华微电子科技有限公司 | With the receiver for stablizing input trigging signal |
| CN109100564A (en) * | 2017-06-21 | 2018-12-28 | 浙江大华技术股份有限公司 | A kind of signal fluctuation detection circuit |
| US11196408B2 (en) | 2017-06-21 | 2021-12-07 | Zhejiang Dahua Technology Co., Ltd. | System and method for mixed transmission of signals and power supply through a single cable |
| CN109347481A (en) * | 2018-09-17 | 2019-02-15 | 南京中感微电子有限公司 | A kind of continuous time plural number band logical sigma-delta analog-digital converter and Bluetooth RF transceiver |
| CN109347481B (en) * | 2018-09-17 | 2022-07-12 | 南京中感微电子有限公司 | Continuous-time complex bandpass sigma-delta analog-to-digital converter and Bluetooth radio frequency transceiver |
| CN109357783A (en) * | 2018-12-21 | 2019-02-19 | 广州市优仪电子科技有限公司 | Temperature sensing circuit |
| CN111257673A (en) * | 2020-02-17 | 2020-06-09 | 广东博智林机器人有限公司 | Capacitor fault detection circuit, detection method and servo drive circuit |
| CN114112169A (en) * | 2020-08-28 | 2022-03-01 | 深圳市帝迈生物技术有限公司 | Pressure detection circuit and blood analysis device |
| CN114326916A (en) * | 2022-01-04 | 2022-04-12 | 上海南芯半导体科技股份有限公司 | Reference voltage detection circuit |
| CN115407180A (en) * | 2022-11-02 | 2022-11-29 | 上海阿米芯光半导体有限责任公司 | Signal intensity detection circuit with adjustable threshold value, threshold voltage adjusting method and hysteresis adjusting method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105450211A (en) | Signal detection circuit | |
| WO2018126634A1 (en) | Detection method and device of charging switch of electric vehicle | |
| US10145885B2 (en) | Electrical leakage detection apparatus | |
| CN102068247B (en) | Method and device for carrying out ECG (Electrocardiograph) lead-off detection | |
| CN101696996B (en) | Pulse width signal duty factor detector | |
| EP2762903B1 (en) | Ac input voltage interruption detection method and circuit | |
| CN103414474B (en) | High-precision small-signal difference analog-digital converter | |
| CN105244848A (en) | Overvoltage protection method and circuit | |
| CN104254783A (en) | An electrostatic discharge event detector | |
| CN110758309B (en) | Voltage type collision detection circuit | |
| CN204287307U (en) | Transformer, current detection circuit based on transformer | |
| CN111900782A (en) | Charging control circuit, charging chip and charging equipment | |
| CN103914189A (en) | Mutual capacitance detecting circuit | |
| CN215340043U (en) | Switching power supply low current detection circuit | |
| CN103236793B (en) | The sample circuit of power converter | |
| CN104333062A (en) | Charging circuit capable of detecting charging current | |
| CN104852558B (en) | Discharge circuit | |
| CN107294383B (en) | A kind of Switching Power Supply | |
| CN201528321U (en) | Pulse-width signal duty ratio detector | |
| CN113484590A (en) | Switching power supply small current detection circuit and switching power supply small current control method | |
| CN106160458A (en) | Improve the BOOST circuit of transient response | |
| US20210018551A1 (en) | Status detection of alarm sounding parts | |
| CN101753003B (en) | Protective device and method of boost converter | |
| CN201237635Y (en) | Battery voltage detector and mobile terminal with the same | |
| US11469739B2 (en) | Filter capacitor discharge circuit, conversion circuit, and operation method of discharging filter capacitor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20160330 |
|
| RJ01 | Rejection of invention patent application after publication |