CN115219781A - Positive and negative voltage sampling circuit and sampling system with same - Google Patents
Positive and negative voltage sampling circuit and sampling system with same Download PDFInfo
- Publication number
- CN115219781A CN115219781A CN202211041636.1A CN202211041636A CN115219781A CN 115219781 A CN115219781 A CN 115219781A CN 202211041636 A CN202211041636 A CN 202211041636A CN 115219781 A CN115219781 A CN 115219781A
- Authority
- CN
- China
- Prior art keywords
- resistor
- level signal
- operational amplifier
- electrically connected
- positive
- 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
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
- G01R19/2506—Arrangements for conditioning or analysing measured signals, e.g. for indicating peak values ; Details concerning sampling, digitizing or waveform capturing
- G01R19/2509—Details concerning sampling, digitizing or waveform capturing
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
The invention discloses a positive and negative voltage sampling circuit and a sampling system with the same, wherein the positive and negative voltage sampling circuit comprises: the device comprises a signal scaling module, a rectifying module, a filtering module and a zero-crossing comparison module; the signal scaling module is used for scaling the received first level signal and outputting a second level signal, wherein the second level signal = a first level signal x Num, and Num is not equal to 0; the rectification module is used for rectifying the second level signal and outputting a third level signal, wherein the third level signal = the absolute value of the second level signal; the filtering module is used for filtering the third level signal and outputting a fourth level signal; when the second level signal is greater than 0, the zero-crossing comparison module outputs a fifth level signal; when the second level signal is less than 0, the zero-crossing comparison module outputs a sixth level signal; one of the fifth level signal and the sixth level signal is greater than zero and the other is equal to zero. Thereby enabling the measurement of negative voltages.
Description
Technical Field
The invention relates to the technical field of electronic circuits, in particular to a positive and negative voltage sampling circuit and a sampling system with the same.
Background
Electrical quantity measurement typically includes measurement of voltage, current, power, etc., where voltage measurement is an indispensable technique in electronic systems. At present, in the embedded field, voltage signals in the environment are often measured through a built-in AD or an external AD pressure measuring chip of a single chip microcomputer, and the minimum resolution of the measured voltage is higher along with the increase of the AD digits. However, these AD modules can only measure the positive voltage input to the pin of the AD module, and if the measured voltage is a negative voltage, the AD module cannot convert the measured negative voltage, and may damage the AD module.
Disclosure of Invention
In view of this, the present invention provides a positive and negative voltage sampling circuit and a sampling system having the same.
In order to achieve the purpose, the technical scheme of the invention is realized as follows: a positive and negative voltage sampling circuit comprising: the device comprises a signal scaling module, a rectifying module, a filtering module and a zero-crossing comparison module; the signal scaling module is used for scaling the received first level signal and outputting a second level signal, wherein the second level signal = a first level signal x Num, and Num is not equal to 0; the rectification module is used for rectifying the second level signal and outputting a third level signal, wherein the third level signal = the absolute value of the second level signal; the filtering module is used for filtering the third level signal and outputting a fourth level signal; when the second level signal is greater than 0, the zero-crossing comparison module outputs a fifth level signal; when the second level signal is less than 0, the zero-crossing comparison module outputs a sixth level signal; one of the fifth level signal and the sixth level signal is greater than zero and the other is equal to zero.
As an improvement of the embodiment of the present invention, num <0.
As a modification of the embodiment of the present invention, the fifth level signal =0, and the sixth level signal >0.
As an improvement of the embodiment of the present invention, the signal scaling module includes: a resistor R9, a resistor R10, a resistor R11 and an operational amplifier U1D; the voltage input by the positive power end of the operational amplifier U1D is greater than 0, and the voltage input by the negative power end is less than 0; a first end of the resistor R10 is electrically connected with the input end Vin, and a second end of the resistor R10 is electrically connected with an inverting end of the operational amplifier U1D; the first end of the resistor R9 is electrically connected with the inverting end of the operational amplifier U1D, and the second end of the resistor R9 is electrically connected with the output end O1 of the operational amplifier U1D; the first end of the resistor R11 is electrically connected with the in-phase end of the operational amplifier U1D, and the second end of the resistor R is grounded; in the resistor R9, the resistor R10 and the resistor R11, the first end and the second end are different ends respectively; the input terminal Vin is used for receiving a first level signal, and the output level signal of the output terminal O1 is a second level signal.
As an improvement of the embodiment of the present invention, the rectifier module includes: the circuit comprises a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a diode D2A, a diode D2B, an operational amplifier U1A and an operational amplifier U1B; the voltage input by the positive power supply end of the operational amplifier U1A is greater than 0, the voltage input by the negative power supply end is less than 0, the voltage input by the positive power supply end of the operational amplifier U1B is greater than 0, and the voltage input by the negative power supply end is less than 0; the first end of the resistor R1 is used for receiving a second level signal, the second end of the resistor R1 is electrically connected to the inverting end of the operational amplifier U1A, and the non-inverting end of the operational amplifier U1A is grounded; a first end of the resistor R4 is electrically connected to a first end of the resistor R1, a second end of the resistor R is electrically connected to an inverting end of the operational amplifier U1B, and a non-inverting end of the operational amplifier U1B is grounded; a second end of the resistor R1 is electrically connected to a first end of the resistor R2, a second end of the resistor R2 is electrically connected to a first end of the resistor R3, and a second end of the resistor R3 is electrically connected to an inverting end of the operational amplifier U1B; a second end of the resistor R1 is electrically connected to a cathode of the diode D2B, an anode of the diode D2B is electrically connected to an output end of the operational amplifier U1A and a cathode of the diode D2A respectively, and an anode of the diode D2A is electrically connected to a second end of the resistor R2; a first end of the resistor R5 is electrically connected to the inverting end of the operational amplifier U1B, and a second end is electrically connected to the output end O2 and the output end O2 of the operational amplifier U1B respectively; in the resistor R1, the resistor R2, the resistor R3, the resistor R4 and the resistor R5, the first end and the second end are different ends respectively; the level signal output by the output terminal O2 is a third level signal.
As an improvement of the embodiment of the present invention, the filtering module includes: a resistor R7 and a capacitor C1; the first end of the resistor R7 is used for receiving a third level signal, the second end of the resistor R7 is electrically connected to the first end of the capacitor C1 and the output end O3 respectively, and the second end of the capacitor C1 is grounded; in the resistor R7, the first and second ends are different ends, respectively; the level signal output by the output terminal O3 is a fourth level signal.
As an improvement of the embodiment of the present invention, the zero-crossing comparing module includes: the circuit comprises a resistor R6, a resistor R8, a resistor R12, a resistor R13, an operational amplifier U1C and a diode D4; the first end of the resistor R6 is used for receiving a second level signal, and the second end of the resistor R is electrically connected to the inverting end of the operational amplifier U1C; the first end of the resistor R12 is grounded, and the second end of the resistor R12 is electrically connected to the non-inverting end of the operational amplifier U1C; the anode of the diode D4 is electrically connected to the output end of the operational amplifier U1C, the cathode is electrically connected to the first end of the resistor R13, the second end of the resistor R13 is electrically connected to the output end O4 and the first end of the resistor R8, respectively, and the second end of the resistor R8 is grounded; the voltage input by the positive power end of the operational amplifier U1C is greater than 0, and the voltage input by the negative power end is less than 0; the output terminal O4 is configured to output a fifth level signal and a sixth level signal.
As an improvement of the embodiment of the present invention, the diode D2A, the diode D2B, and the diode D4 are all germanium diodes.
The embodiment of the invention also provides a sampling system, which comprises the positive and negative voltage sampling circuit, a signal source and a signal measuring device; the signal source can generate a first level signal and input the first level signal into the positive and negative voltage sampling circuit, and the signal measuring device is provided with a first input end and a second input end, wherein the first input end is used for receiving a fourth level signal, and the second input end is used for receiving a fifth level signal and a sixth level signal.
As an improvement of the embodiment of the present invention, the signal measuring device is an MCU.
The positive and negative voltage sampling circuit and the sampling system with the same provided by the embodiment of the invention have the following advantages: the embodiment of the invention discloses a positive and negative voltage sampling circuit and a sampling system with the same, wherein the positive and negative voltage sampling circuit comprises: the device comprises a signal scaling module, a rectifying module, a filtering module and a zero-crossing comparison module; the signal scaling module is used for scaling the received first level signal and outputting a second level signal, wherein the second level signal = a first level signal × Num, and Num is not equal to 0; the rectification module is used for rectifying the second level signal and outputting a third level signal, wherein the third level signal = the absolute value of the second level signal; the filtering module is used for filtering the third level signal and outputting a fourth level signal; when the second level signal is greater than 0, the zero-crossing comparison module outputs a fifth level signal; when the second level signal is less than 0, the zero-crossing comparison module outputs a sixth level signal; one of the fifth level signal and the sixth level signal is greater than zero and the other is equal to zero. Thereby enabling the measurement of negative voltages.
Drawings
Fig. 1 is a schematic structural diagram of a positive and negative voltage sampling circuit according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a signal scaling module according to an embodiment of the present invention;
fig. 3A is a schematic structural diagram of a rectifier module according to an embodiment of the present invention;
FIGS. 3B and 3C are simplified diagrams of a rectifier module according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a filtering module according to an embodiment of the present invention;
fig. 5 is a schematic structural diagram of a zero-crossing comparison module according to an embodiment of the present invention.
Detailed Description
The present invention will be described in detail below with reference to embodiments shown in the drawings. The present invention is not limited to the embodiment, and structural, methodological, or functional changes made by one of ordinary skill in the art according to the embodiment are included in the scope of the present invention.
The following description and the drawings sufficiently illustrate specific embodiments herein to enable those skilled in the art to practice them. Portions and features of some embodiments may be included in or substituted for those of others. The scope of the embodiments herein includes the full ambit of the claims, as well as all available equivalents of the claims. The terms "first," "second," and the like, herein are used solely to distinguish one element from another without requiring or implying any actual such relationship or order between such elements. In practice, a first element can also be referred to as a second element, and vice versa. Furthermore, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a structure, apparatus, or device that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such structure, apparatus, or device. Without further limitation, an element defined by the phrase "comprising a … …" does not exclude the presence of another like element in a structure, device, or apparatus that comprises the element. The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
The terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like herein, as used herein, are defined as orientations or positional relationships based on the orientation or positional relationship shown in the drawings, and are used for convenience in describing and simplifying the description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention. In the description herein, unless otherwise specified and limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may include, for example, mechanical or electrical connections, communications between two elements, direct connections, and indirect connections via intermediary media, where the specific meaning of the terms is understood by those skilled in the art as appropriate.
For convenience of description, in this document, the voltage of the positive level signal is greater than zero, the level signal of GND is equal to zero, and the voltage of the negative level signal is less than zero.
An embodiment of the present invention provides a positive and negative voltage sampling circuit, as shown in fig. 1, including:
the device comprises a signal scaling module 1, a rectifying module 2, a filtering module 3 and a zero-crossing comparison module 4; the signal scaling module 1 is configured to scale the received first level signal and output a second level signal, where the second level signal = the first level signal × Num, and Num ≠ 0; the rectification module 2 is configured to rectify the second level signal and output a third level signal, where the third level signal = an absolute value of the second level signal; the filtering module 3 is used for filtering the third level signal and outputting a fourth level signal; when the second level signal is greater than 0, the zero-crossing comparison module 4 outputs a fifth level signal; when the second level signal is less than 0, the zero-crossing comparison module 4 outputs a sixth level signal; one of the fifth level signal and the sixth level signal is greater than zero and the other is equal to zero.
Here, in actual use, the absolute value of the first level signal may be relatively large or relatively small, and therefore, for convenience of measurement, the signal scaling module 1 is provided in the positive and negative voltage sampling circuit, the signal scaling module 1 can scale the first level signal by Num times to output the second level signal, and the third level signal output through the rectification module 2= the absolute value of the second level signal, and thereafter, the third level signal outputs the fourth level signal through the filtering process. Further, it is possible to determine whether the first level signal is a positive level signal or a negative level signal from the output of the zero-cross comparison block 4.
In this embodiment, num <0.
In this embodiment, the fifth level signal =0, and the sixth level signal >0. Here, the fifth and sixth level signals are both greater than zero, and therefore, the received level signals are both positive level signals by the signal sampling module.
In this embodiment, the signal scaling module 1 includes: a resistor R9, a resistor R10, a resistor R11 and an operational amplifier U1D; the voltage input by the positive power supply end of the operational amplifier U1D is greater than 0, and the voltage input by the negative power supply end is less than 0; a first end of the resistor R10 is electrically connected with the input end Vin, and a second end of the resistor R10 is electrically connected with an inverting end of the operational amplifier U1D; the first end of the resistor R9 is electrically connected with the inverting end of the operational amplifier U1D, and the second end of the resistor R9 is electrically connected with the output end O1 of the operational amplifier U1D; the first end of the resistor R11 is electrically connected with the in-phase end of the operational amplifier U1D, and the second end of the resistor R is grounded; in the resistor R9, the resistor R10 and the resistor R11, the first end and the second end are different ends respectively; the input terminal Vin is used for receiving a first level signal, and the output level signal of the output terminal O1 is a second level signal.
Here, when a positive level signal (i.e., greater than zero) is input to the input terminal Vin, the voltage of the output terminal O1 is negative and is limited to be near the voltage input by the negative power supply. When a negative level signal (i.e., less than zero) is input to the input terminal Vin, the voltage at the output terminal O1 becomes positive and is limited to be close to the voltage input by the positive power supply. It is understood that the output terminal O1 is the level signal/the level signal input by the input terminal Vin = -1 × R9/R10, and R11= R10// R9.
In this embodiment, as shown in fig. 3A, 3B and 3C, the rectifier module 2 includes: the circuit comprises a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a diode D2A, a diode D2B, an operational amplifier U1A and an operational amplifier U1B; the voltage input by the positive power supply end of the operational amplifier U1A is greater than 0, the voltage input by the negative power supply end is less than 0, the voltage input by the positive power supply end of the operational amplifier U1B is greater than 0, and the voltage input by the negative power supply end is less than 0; the first end of the resistor R1 is used for receiving a second level signal, the second end of the resistor R1 is electrically connected to the inverting end of the operational amplifier U1A, and the non-inverting end of the operational amplifier U1A is grounded; a first end of the resistor R4 is electrically connected to a first end of the resistor R1, a second end of the resistor R is electrically connected to an inverting end of the operational amplifier U1B, and a non-inverting end of the operational amplifier U1B is grounded; a second end of the resistor R1 is electrically connected to a first end of the resistor R2, a second end of the resistor R2 is electrically connected to a first end of the resistor R3, and a second end of the resistor R3 is electrically connected to an inverting end of the operational amplifier U1B; the second end of the resistor R1 is electrically connected to the cathode of the diode D2B, the anode of the diode D2B is electrically connected to the output end of the operational amplifier U1A and the cathode of the diode D2A respectively, and the anode of the diode D2A is electrically connected to the second end of the resistor R2; a first end of the resistor R5 is electrically connected to the inverting end of the operational amplifier U1B, and a second end is electrically connected to the output end O2 and the output end O2 of the operational amplifier U1B respectively; in the resistor R1, the resistor R2, the resistor R3, the resistor R4 and the resistor R5, the first end and the second end are different ends respectively; the level signal output by the output terminal O2 is a third level signal.
Here, when the output of the output terminal O1 is a positive level signal Vi (Vi > 0), the potential of the non-inverting terminal of the operational amplifier U1A is lower than the potential of the inverting terminal, and the voltage output from the output terminal of the operational amplifier U1A is negative, so that the diode D1 is turned off, the diode D2 is turned on, the operational amplifier U1B constitutes an inverting amplifier having a gain of-1, and the output is-Vi, and the equivalent circuit diagram at this time is as shown in fig. 3B. The following equations can be drawn from the virtual short and KCL equations: (0- (-Vi))/R3 + (0-Vi)/R4 + (0-O2)/R5 =0, yielding: o2= Vi.
Here, when the output of the output terminal O1 is a negative level signal — Vi (Vi > 0), the potential of the non-inverting terminal of the operational amplifier U1A is higher than the potential of the inverting terminal, and the voltage output from the output terminal of the operational amplifier U1A is positive, so that the diode D2 is turned off, and the potentials of the first terminal of the resistor R2 and the second terminal of the resistor R3 are 0 due to the virtual short of the operational amplifier U1A, and no current flows. The operational amplifier U1A is equivalent to being disconnected from the circuit. Only the operational amplifier U1B is operated, and the operational amplifier U1B is analyzed, and the equivalent circuit diagram is shown in fig. 3C, and the operational amplifier U1B is an inverting amplifier with a gain of-1. So O2= -Vi.
In summary, the function of the rectifier module 2 is that the level signal at the output terminal O2= the absolute value of the level signal at the output terminal O1.
In this embodiment, as shown in fig. 4, the filtering module 3 includes: a resistor R7 and a capacitor C1; the first end of the resistor R7 is used for receiving a third level signal, the second end of the resistor R7 is respectively and electrically connected to the first end of the capacitor C1 and the output end O3, and the second end of the capacitor C1 is grounded; in the resistor R7, the first end and the second end are different ends respectively; the level signal output by the output terminal O3 is a fourth level signal. Here, the resistor R6 divides the level signal input from the output terminal O2 in proportion and discharges the energy of the output capacitor C1, thereby achieving the filtering effect.
In this embodiment, as shown in fig. 5, the zero-crossing comparing module 4 includes: the circuit comprises a resistor R6, a resistor R8, a resistor R12, a resistor R13, an operational amplifier U1C and a diode D4; the first end of the resistor R6 is used for receiving a second level signal, and the second end of the resistor R is electrically connected to the inverting end of the operational amplifier U1C; the first end of the resistor R12 is grounded, and the second end of the resistor R12 is electrically connected to the non-inverting end of the operational amplifier U1C; the anode of the diode D4 is electrically connected to the output end of the operational amplifier U1C, the cathode is electrically connected to the first end of the resistor R13, the second end of the resistor R13 is electrically connected to the output end O4 and the first end of the resistor R8, respectively, and the second end of the resistor R8 is grounded; the voltage input by the positive power end of the operational amplifier U1C is greater than 0, and the voltage input by the negative power end is less than 0; the output terminal O4 is configured to output a fifth level signal and a sixth level signal.
When the second level signal is negative level, the input voltage received by the operational amplifier U1C is negative, because the inverting terminal of the operational amplifier U1C is negative and the positive input terminal is 0V, the output voltage approaches the positive power voltage, and the output terminal of the operational amplifier U1C passes through the diode D4, the resistor R13 and the resistor R8 form a loop, the resistor R13 and the resistor R8 form a voltage divider circuit to limit the voltage within a range, and at this time, the output terminal O4 outputs a positive level signal.
When the second level signal is positive, the input voltage received by the operational amplifier U1C is positive, since the reverse end of the operational amplifier U1C is positive, and the forward input end is 0V, the output voltage is close to the negative power voltage, and the diode D4 prevents the current from being transmitted back to the output end of the operational amplifier U1C through the resistor R8 and the resistor R13, which is equivalent to an open circuit. Therefore, R8 is a pull-down resistor, and the voltage at V2 is 0V. And inputting the V2 into a common IO port of the MCU, and configuring IO into a floating input state.
In this embodiment, the diode D2A, the diode D2B, and the diode D4 are all germanium diodes. The germanium diode has the advantage of low voltage drop.
The embodiment II of the invention provides a sampling system, which comprises a positive and negative voltage sampling circuit, a signal source and a signal measuring device in the embodiment I; the signal source can generate a first level signal and input the first level signal into the positive and negative voltage sampling circuit, and the signal measuring device is provided with a first input end and a second input end, wherein the first input end is used for receiving a fourth level signal, and the second input end is used for receiving a fifth level signal and a sixth level signal.
Optionally, the signal measuring device is an MCU (micro controller Unit), an ADC (Analog to Digital Converter) module is disposed in the MCU, and the first input terminal is electrically connected to the ADC module, that is, the ADC module performs Analog-to-Digital conversion on the fourth level signal. In actual use, the output end O4 can be input into a common IO port of the MCU, and the IO is configured in a floating input state.
In this embodiment, the signal measuring device is an MCU.
It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.
The above-listed detailed description is merely a detailed description of possible embodiments of the present invention, and it is not intended to limit the scope of the invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. A positive-negative voltage sampling circuit, comprising:
the device comprises a signal scaling module (1), a rectifying module (2), a filtering module (3) and a zero-crossing comparison module (4);
the signal scaling module (1) is configured to scale the received first level signal and output a second level signal, where the second level signal = the first level signal × Num, and Num ≠ 0;
the rectification module (2) is used for rectifying the second level signal and outputting a third level signal, wherein the third level signal = the absolute value of the second level signal; the filtering module (3) is used for filtering the third level signal and outputting a fourth level signal;
when the second level signal is greater than 0, the zero-crossing comparison module (4) outputs a fifth level signal; when the second level signal is less than 0, the zero-crossing comparison module (4) outputs a sixth level signal; one of the fifth level signal and the sixth level signal is greater than zero and the other is equal to zero.
2. The positive-negative voltage sampling circuit of claim 1, wherein:
Num<0。
3. the positive-negative voltage sampling circuit of claim 1, wherein:
fifth level signal =0, sixth level signal >0.
4. The positive-negative voltage sampling circuit according to claim 1, characterized in that the signal scaling module (1) comprises:
the resistor R9, the resistor R10, the resistor R11 and the operational amplifier U1D; the voltage input by the positive power end of the operational amplifier U1D is greater than 0, and the voltage input by the negative power end is less than 0;
the first end of the resistor R10 is electrically connected with the input end Vin, and the second end of the resistor R is electrically connected with the inverting end of the operational amplifier U1D; the first end of the resistor R9 is electrically connected with the inverting end of the operational amplifier U1D, and the second end of the resistor R is electrically connected with the output end O1 of the operational amplifier U1D; the first end of the resistor R11 is electrically connected with the in-phase end of the operational amplifier U1D, and the second end of the resistor R is grounded; in the resistor R9, the resistor R10 and the resistor R11, the first end and the second end are different ends respectively;
the input terminal Vin is used for receiving a first level signal, and the output level signal of the output terminal O1 is a second level signal.
5. The positive-negative voltage sampling circuit according to claim 1, characterized in that the rectifying module (2) comprises:
the circuit comprises a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a diode D2A, a diode D2B, an operational amplifier U1A and an operational amplifier U1B; the voltage input by the positive power end of the operational amplifier U1A is greater than 0, the voltage input by the negative power end is less than 0, the voltage input by the positive power end of the operational amplifier U1B is greater than 0, and the voltage input by the negative power end is less than 0;
the first end of the resistor R1 is used for receiving a second level signal, the second end of the resistor R1 is electrically connected to the inverting end of the operational amplifier U1A, and the non-inverting end of the operational amplifier U1A is grounded;
a first end of the resistor R4 is electrically connected to a first end of the resistor R1, a second end of the resistor R is electrically connected to an inverting end of the operational amplifier U1B, and a non-inverting end of the operational amplifier U1B is grounded;
a second end of the resistor R1 is electrically connected to a first end of the resistor R2, a second end of the resistor R2 is electrically connected to a first end of the resistor R3, and a second end of the resistor R3 is electrically connected to an inverting end of the operational amplifier U1B;
a second end of the resistor R1 is electrically connected to a cathode of the diode D2B, an anode of the diode D2B is electrically connected to an output end of the operational amplifier U1A and a cathode of the diode D2A respectively, and an anode of the diode D2A is electrically connected to a second end of the resistor R2;
a first end of the resistor R5 is electrically connected to the inverting end of the operational amplifier U1B, and a second end is electrically connected to the output end O2 and the output end O2 of the operational amplifier U1B respectively;
in the resistor R1, the resistor R2, the resistor R3, the resistor R4 and the resistor R5, the first end and the second end are different ends respectively; the level signal output by the output terminal O2 is a third level signal.
6. The positive-negative voltage sampling circuit according to claim 1, characterized in that the filtering module (3) comprises:
a resistor R7 and a capacitor C1;
the first end of the resistor R7 is used for receiving a third level signal, the second end of the resistor R7 is respectively and electrically connected to the first end of the capacitor C1 and the output end O3, and the second end of the capacitor C1 is grounded;
in the resistor R7, the first and second ends are different ends, respectively; the level signal output by the output terminal O3 is a fourth level signal.
7. The positive-negative voltage sampling circuit according to claim 1, wherein the zero-crossing comparison module (4) comprises:
the circuit comprises a resistor R6, a resistor R8, a resistor R12, a resistor R13, an operational amplifier U1C and a diode D4;
the first end of the resistor R6 is used for receiving a second level signal, and the second end of the resistor R is electrically connected to the inverting end of the operational amplifier U1C;
the first end of the resistor R12 is grounded, and the second end of the resistor R12 is electrically connected to the non-inverting end of the operational amplifier U1C;
the anode of the diode D4 is electrically connected to the output end of the operational amplifier U1C, the cathode is electrically connected to the first end of the resistor R13, the second end of the resistor R13 is electrically connected to the output end O4 and the first end of the resistor R8, respectively, and the second end of the resistor R8 is grounded;
the voltage input by the positive power end of the operational amplifier U1C is greater than 0, and the voltage input by the negative power end is less than 0;
the output end O4 is used for outputting a fifth level signal and a sixth level signal;
the first and second ends of the resistor R6, the resistor R8, the resistor R12, and the resistor R13 are different ends, respectively.
8. The positive-negative voltage sampling circuit according to any one of claims 2 to 7, wherein:
the diode D2A, the diode D2B, and the diode D4 are all germanium diodes.
9. A sampling system, characterized by:
comprising a positive and negative voltage sampling circuit according to any one of claims 1 to 8, a signal source and a signal measuring device;
the signal source can generate a first level signal and input the first level signal into the positive and negative voltage sampling circuit,
the signal measuring device has a first input for receiving a fourth level signal and a second input for receiving a fifth level signal and a sixth level signal.
10. The sampling system of claim 9, wherein:
the signal measuring device is an MCU.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211041636.1A CN115219781A (en) | 2022-08-29 | 2022-08-29 | Positive and negative voltage sampling circuit and sampling system with same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211041636.1A CN115219781A (en) | 2022-08-29 | 2022-08-29 | Positive and negative voltage sampling circuit and sampling system with same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115219781A true CN115219781A (en) | 2022-10-21 |
Family
ID=83617157
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211041636.1A Pending CN115219781A (en) | 2022-08-29 | 2022-08-29 | Positive and negative voltage sampling circuit and sampling system with same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115219781A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116761115A (en) * | 2023-08-11 | 2023-09-15 | 上海海栎创科技股份有限公司 | Low-cost high-efficiency playback power supply control circuit and control method |
-
2022
- 2022-08-29 CN CN202211041636.1A patent/CN115219781A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116761115A (en) * | 2023-08-11 | 2023-09-15 | 上海海栎创科技股份有限公司 | Low-cost high-efficiency playback power supply control circuit and control method |
| CN116761115B (en) * | 2023-08-11 | 2023-12-12 | 上海海栎创科技股份有限公司 | Low-cost high-efficiency playback power supply control circuit and control method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR20080021143A (en) | Capacitance-to-voltage conversion method and apparatus | |
| CN101930026A (en) | Electronic device with power loss detection function | |
| CN115219781A (en) | Positive and negative voltage sampling circuit and sampling system with same | |
| CN206922415U (en) | A kind of under-voltage protecting circuit of onboard system, auto meter and vehicle | |
| CN109541291A (en) | Wide temperature high-precision multichannel current acquisition system | |
| CN103499991B (en) | The analog-to-digital conversion circuit of tool temperature sensing and electronic installation thereof | |
| CN101335460B (en) | Battery cutoff voltage setting system and setting method thereof | |
| CN218003548U (en) | Positive and negative voltage sampling circuit and sampling system with same | |
| US8354859B2 (en) | System for testing power supply performance | |
| US20150185817A1 (en) | Charging circuit for usb interface | |
| CN209963797U (en) | Charging protection circuit and charging system | |
| CN217063681U (en) | High-precision clock generation circuit with digital temperature compensation | |
| US11604101B2 (en) | Temperature measuring circuit and measuring method thereof | |
| CN114744854B (en) | Power supply circuit and power supply chip | |
| CN205304767U (en) | Analog to digital conversion circuit with two reference sources | |
| CN209842087U (en) | External equipment detection circuit and electronic equipment | |
| CN215956537U (en) | Projection control system | |
| US11855660B2 (en) | Sigma-delta analog-to-digital converter and sensor arrangements including the same | |
| CN109728816A (en) | A kind of ADC condition detecting system | |
| CN113691275B (en) | Digital signal transmission circuit and digital signal transmission device | |
| CN220709253U (en) | Signal sampling circuit, battery management system and power utilization device | |
| CN113726178B (en) | Switch converter and detection circuit thereof | |
| CN219369870U (en) | Zero-crossing detection circuit and electrical equipment | |
| CN214538341U (en) | Pressure sensing circuit | |
| CN210743109U (en) | High-reliability payment device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |