CN209946245U - Voltage maximum value comparison circuit - Google Patents
Voltage maximum value comparison circuit Download PDFInfo
- Publication number
- CN209946245U CN209946245U CN201822066668.2U CN201822066668U CN209946245U CN 209946245 U CN209946245 U CN 209946245U CN 201822066668 U CN201822066668 U CN 201822066668U CN 209946245 U CN209946245 U CN 209946245U
- Authority
- CN
- China
- Prior art keywords
- resistor
- voltage
- input
- reference voltage
- diode
- 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
Abstract
The utility model provides a voltage maximum value comparison circuit, which is used for obtaining the maximum value of N-path input voltage, wherein N is an integer more than or equal to 2; the voltage maximum value comparison circuit comprises a detection unit and a comparison unit; the detection unit comprises N input terminals, each input terminal is connected with one input voltage, the output end of the detection unit is connected with the comparison unit, and the most value of the N input voltages is output to the input end of the comparison unit; the comparison unit is connected to the reference voltage and generates an output signal according to a comparison result of the most significant value of the input terminal and the reference voltage. The utility model only needs two voltage comparators, and only needs to add a diode in the detection unit to realize circuit expansion when adding one path of voltage input, the circuit expansibility is better, the cost is saved, and the occupied space on the PCB board is smaller; the comparison unit and the reference voltage generation unit select the same diode and pull-up and pull-down resistor types, so that the reference voltage does not change along with temperature change, and the application range is wide.
Description
Technical Field
The embodiment of the utility model provides a relate to the power electronics field, more specifically say, relate to a voltage comparison circuit at most.
Background
The maximum value (maximum value and minimum value) of the voltage is commonly applied to overvoltage, undervoltage or overcurrent detection of industrial control, power electronics, automotive electronics and the like, and a voltage comparator is generally adopted for the maximum value comparison of the voltage. The voltage comparator may be regarded as an operational amplifier with an amplification factor close to "infinity", and functions to compare the magnitudes of two input voltages (or a reference voltage and a voltage to be compared) and represent the comparison result of the two input voltages with a high level or a low level of an output voltage. When the voltage of the non-inverting input end is higher than the voltage of the inverting input end, the output is high level; when the voltage at the non-inverting input "+" is lower than the voltage at the inverting input "-", the output is low.
If the maximum value and the minimum value are compared at the same time, a circuit scheme of interval comparison is generally adopted. If the most value comparison is performed on multiple voltages, the output of the comparator is directly connected, because the output of the comparator is an open collector output, and therefore the circuit is similar to the form of a wired-and, and the circuit form is shown in fig. 1. The reference voltage setting is in the form of resistance voltage division, as shown in fig. 2.
For the multi-path voltage comparison, a comparator output wired-and mode is adopted, and the main disadvantages are that each time the comparison of one path of voltage signal is added, a comparator needs to be added, the cost is high, and the comparator device needs to occupy a large area on a Printed Circuit Board (PCB).
SUMMERY OF THE UTILITY MODEL
The embodiment of the utility model provides a maximum comparison circuit of voltage drop aims at solving the form that multichannel voltage comparison adopted comparator output "line and" among the prior art, and the cost is higher, and the comparator device need occupy the problem of great area on the PCB board.
The embodiment of the present invention provides a voltage maximum value comparison circuit for obtaining the maximum value of N input voltages, where N is an integer greater than or equal to 2; the voltage maximum value comparison circuit comprises a detection unit and a comparison unit, wherein: the detection unit comprises N input terminals, each input terminal is connected with one path of input voltage, the output end of the detection unit is connected with the comparison unit, and the most value of the N paths of input voltages is output to the input end of the comparison unit; the comparison unit is connected to a reference voltage and generates an output signal according to a comparison result of the most significant value of the input terminal and the reference voltage.
In the present invention, the detection unit includes a minimum detection subunit, and the comparison unit includes a first comparator; the minimum detection subunit comprises N first input terminals, each of the first input terminals is connected to one of the input voltages, and an output end of the minimum detection subunit is connected to a non-inverting input end of the first comparator and outputs a minimum value of the N input voltages to the non-inverting input end of the first comparator; the inverting input of the first comparator is connected to a minimum reference voltage.
In the present invention, the detection unit comprises a maximum detection subunit, and the comparison unit comprises a second comparator; the maximum value detection subunit comprises N second input terminals, each second input terminal is connected with one path of the input voltage, the output end of the maximum value detection subunit is connected to the inverting input end of the second comparator, and the maximum value of the N paths of input voltages is output to the inverting input end of the second comparator; the non-inverting input of the second comparator is connected to a maximum reference voltage.
In the present invention, the minimum detector sub-unit includes a first resistor and N first diodes; wherein a first end of the first resistor is connected to an output end of the minimum detector subunit, and a second end of the first resistor is connected to a high level; the cathode of each first diode is connected to one first input terminal, and the anodes of the N first diodes are connected in parallel to the first end of the first resistor.
In the present invention, the maximum detection subunit includes a second resistor and N second diodes; wherein a first end of the second resistor is connected to an output end of the maximum value detection subunit, and a second end of the second resistor is connected to a zero potential; the anode of each second diode is connected to one second input terminal, and the cathodes of the N second diodes are connected in parallel to the first end of the second resistor.
In the present invention, the voltage maximum value comparison circuit further includes a first reference voltage generation unit, an output end of the first reference voltage generation unit is connected to an inverting input end of the first comparator; the first reference voltage generating unit comprises a third resistor, a fourth resistor, a fifth resistor and a third diode; a first end of the third resistor is connected to a high level, and a second end of the third resistor is connected to an output end of the first reference voltage generation unit; the fourth resistor and the fifth resistor are connected in series between a high level and a zero potential; the cathode of the third diode is connected to the connection point of the fourth resistor and the fifth resistor, and the anode of the third diode is connected to the second end of the third resistor.
The embodiment of the present invention provides a maximum voltage comparison circuit, wherein the third resistor has the same resistance as the first resistor, and the third diode has the same type as the first diode.
In the present invention, the maximum voltage comparison circuit further includes a second reference voltage generation unit, and an output terminal of the second reference voltage generation unit is connected to a non-inverting input terminal of the second comparator; the second reference voltage generating unit comprises a sixth resistor, a seventh resistor, an eighth resistor and a fourth diode; a first end of the sixth resistor is connected to a zero potential, and a second end of the sixth resistor is connected to an output end of the second reference voltage generation unit; the seventh resistor and the eighth resistor are connected in series between a high level and a zero potential; an anode of the fourth diode is connected to a connection point of the seventh resistor and the eighth resistor, and a cathode of the fourth diode is connected to a second end of the sixth resistor.
The embodiment of the present invention provides a maximum voltage comparison circuit, wherein the sixth resistor has the same resistance as the second resistor, and the fourth diode has the same type as the second diode.
The embodiment of the utility model provides a most value comparison circuit of voltage satisfies the most value comparison to multichannel voltage, only needs two voltage comparators, and every increase voltage input of the same kind only need increase an input terminal and a diode can realize circuit expansion in the detection unit, and circuit expansibility is better, and the cost is more economized, and the space that occupies is less on the PCB board; the comparison unit and the reference voltage generation unit can compensate the influence of temperature change on the most significant comparison value by selecting the same diode and pull-up and pull-down resistor types, the reference voltage does not change along with the temperature change, and the application range is wide.
Drawings
FIG. 1 is a schematic diagram of a prior art voltage maximum comparison circuit;
FIG. 2 is a schematic diagram of a reference voltage generating circuit in a prior art maximum voltage comparison circuit;
fig. 3 is a schematic diagram of a voltage maximum comparison circuit provided by an embodiment of the present invention;
fig. 4 is a schematic diagram of a first reference voltage generating unit in a maximum voltage comparison circuit according to an embodiment of the present invention;
fig. 5 is a schematic diagram of a second reference voltage generating unit in the maximum voltage comparison circuit according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
As shown in fig. 3, which is a schematic diagram of a maximum voltage comparison circuit according to an embodiment of the present invention, the maximum voltage comparison circuit is used to obtain the maximum values of N input voltages (V1, V2, … … Vn), where N is an integer greater than or equal to 2; the voltage maximum value comparison circuit comprises a detection unit 1 and a comparison unit 2, wherein: the detection unit 1 comprises N input terminals, each input terminal is connected with one input voltage, the output end of the detection unit 1 is connected with the comparison unit 2, and the most value of the N input voltages is output to the input end of the comparison unit 2; the comparing unit 2 is connected to the reference voltage and generates an output signal according to a result of comparison of the most significant value of the input terminal and the reference voltage.
Specifically, the above-described detection unit 1 includes a minimum value detection subunit 11, and the comparison unit 2 includes a first comparator 21; the minimum detection subunit includes N first input terminals, each of the first input terminals is connected to one input voltage, an output terminal of the minimum detection subunit 11 is connected to a non-inverting input terminal of the first comparator 21, and outputs a minimum value of the N input voltages to the non-inverting input terminal of the first comparator 21; the inverting input terminal of the first comparator 21 is connected to the minimum value reference voltage V _ L.
The minimum detector sub-unit 11 is configured to compare the magnitudes of the N input voltages and output a minimum value, and specifically includes a first resistor (pull-up resistor) R1 and N first diodes (D11, D12, … … D1N); wherein, a first end of the first resistor R1 is connected to the output end of the minimum detector subunit 11, and a second end of the first resistor R1 is connected to high level; the cathode of each first diode is connected to a first input terminal, and the anodes of the N first diodes are connected in parallel to a first end of a first resistor R1. Form a "wired and" form and output a minimum value.
The detector unit 1 further includes a maximum value detector sub-unit 12, and the comparator unit 2 includes a second comparator 22; the maximum value detection subunit 12 includes N second input terminals, each of which is connected to one input voltage, and an output terminal of the maximum value detection subunit 12 is connected to an inverting input terminal of the second comparator 22, and outputs a maximum value of the N input voltages to the inverting input terminal of the second comparator 22; the non-inverting input of the second comparator 22 is connected to the maximum value reference voltage V _ H.
The maximum value detector unit 12 includes a second resistor R2 and N second diodes (D21, D22, … … D2N); wherein a first terminal of the second resistor R2 is connected to the output terminal of the maximum detector subunit 12, and a second terminal of the second resistor R2 is connected to the zero potential GND; the anodes of the N second diodes are connected to a second input terminal, and the cathodes of the N second diodes are connected in parallel to a first terminal of a second resistor R2, forming a wired-or form, and outputting the maximum value.
The embodiment of the utility model provides a most value comparison circuit of voltage satisfies the most value to multichannel voltage and compares, only needs two voltage comparator, and every increase voltage input of the same kind only need increase an input terminal and a diode and can realize that the circuit extends at detection unit 1, and circuit expansibility is better, and the cost is more economized, and the space that occupies on the PCB board is less.
As shown in fig. 4, the maximum voltage comparison circuit further includes a first reference voltage generation unit 3, an output terminal of the first reference voltage generation unit 3 is connected to an inverting input terminal of the first comparator 21, and the first reference voltage generation unit is used for generating a minimum reference voltage V for comparing with a minimum voltage of the N input voltages-L; the first reference voltage generating unit 3 specifically includes a third resistor R3, a fourth resistor R4, a fifth resistor R5, and a third diode D3; wherein a first terminal of the third resistor R3 is connected to a high level, and a second terminal of the third resistor R3 is connected to an output terminal of the first reference voltage generating unit 3; the fourth resistor R4 and the fifth resistor R5 are connected in series between the high level Vcc and the zero potential GND; a cathode of the third diode D3 is connected to a connection point of the fourth resistor R4 and the fifth resistor R5, and an anode of the third diode D3 is connected to a second end of the third resistor R3.
In particular, since there are N first diodes in the minimum value detection unit 11, which causes the difference between the + voltage of the non-inverting input terminal of the first comparator 21 in the comparison unit 2 and the input of the N voltages to be compared by one diode, for example, the voltage drop of D11, the voltage drop of one diode between the connection point of the fourth resistor R4 and the fifth resistor R5 and the inverting input terminal of the first comparator 21, that is, the third diode D3, is also set in the first reference voltage generation unit 3, and since the conduction voltage drop of the diodes varies with the temperature, the difference between the diodes of different types is relatively large, and therefore the third diode D3 needs to be selected to be of the same type as the N first diodes.
In addition, since the conduction voltage drop of the diode varies depending on the conduction current, it is also ensured that the currents are uniform when the comparison threshold is reached, and therefore, it is ensured that the third resistor R3 in the first reference voltage generation unit 3 has the same resistance value as the first resistor R1 in the minimum value detection subunit 11.
The embodiment of the utility model provides a most value comparison circuit of voltage detects the most value circuit scheme of multichannel input voltage through the diode common cathode or common anode's mode, and comparing element and reference voltage produce the unit and choose the same diode and pull up the resistance type from top to bottom for use, can compensate the temperature variation to the influence of most value comparison value, and reference voltage does not change along with temperature variation, and application scope is wider.
As shown in fig. 5, the maximum value comparison circuit further includes a second reference voltage generation unit 4, an output terminal of the second reference voltage generation unit 4 is connected to a non-inverting input terminal of the second comparator 22, and is configured to generate a maximum value reference voltage to be compared with a maximum voltage of the N input voltages; the second reference voltage generating unit 4 specifically includes a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a fourth diode D4; wherein, a first end of the sixth resistor R6 is connected to the zero potential, and a second end of the sixth resistor R6 is connected to the output end of the second reference voltage generating unit 4; the seventh resistor R7 and the eighth resistor R8 are connected in series between the high level and the zero potential; an anode of the fourth diode D4 is connected to a connection point of the seventh resistor R7 and the eighth resistor R8, and a cathode of the fourth diode D4 is connected to a second end of the sixth resistor R6.
Similarly, since there are N second diodes in the maximum value detection subunit 12, which causes the difference between the voltage at the inverting input terminal of the second comparator 22 in the comparison unit 2 and the input of the N voltages to be compared by one diode, for example, the voltage drop of D21, the difference between the connection point of the seventh resistor R7 and the eighth resistor R8 and the non-inverting input terminal of the second comparator 22, which is the voltage drop of a diode, is set in the second reference voltage generation unit 4, which is the fourth diode D4, and since the conduction voltage drop of the diodes varies with the temperature, the difference between the diodes of different types is relatively large, so the fourth diode D4 is selected to be the same type as the N second diodes.
Since the conduction voltage drop of the diode varies depending on the conduction current therein, it is also ensured that the current is uniform when the comparison threshold is reached, and therefore it is ensured that the resistance value of the sixth resistor R6 in the second reference voltage generating unit 4 is equal to the resistance value of the second resistor R2 in the maximum value detecting sub-unit 12.
In the comparison unit 2, the minimum and maximum voltages detected by the minimum detection subunit 11 and the maximum detection subunit 12 are compared by the first comparator 21 and the second comparator 22, respectively, and the outputs of the two comparators in fig. 1 are combined into one output Vout signal, but may be output separately.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are also within the scope of the embodiments of the present invention. Therefore, the protection scope of the embodiments of the present invention shall be subject to the protection scope of the claims.
Claims (9)
1. A voltage maximum value comparison circuit is used for obtaining the maximum value of N paths of input voltages, wherein N is an integer greater than or equal to 2; the voltage maximum value comparison circuit is characterized by comprising a detection unit and a comparison unit, wherein: the detection unit comprises N input terminals, each input terminal is connected with one path of input voltage, the output end of the detection unit is connected with the comparison unit, and the most value of the N paths of input voltages is output to the input end of the comparison unit; the comparison unit is connected to a reference voltage and generates an output signal according to a comparison result of the most significant value of the input terminal and the reference voltage.
2. The maximum-voltage comparison circuit according to claim 1, wherein the detection unit includes a minimum-value detection subunit, and the comparison unit includes a first comparator; the minimum detection subunit comprises N first input terminals, each of the first input terminals is connected to one of the input voltages, and an output end of the minimum detection subunit is connected to a non-inverting input end of the first comparator and outputs a minimum value of the N input voltages to the non-inverting input end of the first comparator; the inverting input of the first comparator is connected to a minimum reference voltage.
3. The maximum voltage comparison circuit according to claim 1 or 2, wherein the detection unit includes a maximum detection subunit, and the comparison unit includes a second comparator; the maximum value detection subunit comprises N second input terminals, each second input terminal is connected with one path of the input voltage, the output end of the maximum value detection subunit is connected to the inverting input end of the second comparator, and the maximum value of the N paths of input voltages is output to the inverting input end of the second comparator; the non-inverting input of the second comparator is connected to a maximum reference voltage.
4. The vom comparison circuit of claim 2, wherein the minimum detector subunit comprises a first resistor and N first diodes; wherein a first end of the first resistor is connected to an output end of the minimum detector subunit, and a second end of the first resistor is connected to a high level; the cathode of each first diode is connected to one first input terminal, and the anodes of the N first diodes are connected in parallel to the first end of the first resistor.
5. The maximum voltage comparison circuit of claim 3, wherein the maximum detection subunit comprises a second resistor and N second diodes; wherein a first end of the second resistor is connected to an output end of the maximum value detection subunit, and a second end of the second resistor is connected to a zero potential; the anode of each second diode is connected to one second input terminal, and the cathodes of the N second diodes are connected in parallel to the first end of the second resistor.
6. The most-voltage-compared circuit of claim 4, further comprising a first reference voltage generating unit, an output terminal of the first reference voltage generating unit being connected to an inverting input terminal of the first comparator; the first reference voltage generating unit comprises a third resistor, a fourth resistor, a fifth resistor and a third diode; a first end of the third resistor is connected to a high level, and a second end of the third resistor is connected to an output end of the first reference voltage generation unit; the fourth resistor and the fifth resistor are connected in series between a high level and a zero potential; the cathode of the third diode is connected to the connection point of the fourth resistor and the fifth resistor, and the anode of the third diode is connected to the second end of the third resistor.
7. The VSMMD of claim 6, wherein the third resistor has a resistance equal to that of the first resistor, and the third diode is of the same type as each of the first diodes.
8. The voltage maximum comparison circuit of claim 5, further comprising a second reference voltage generation unit, wherein an output terminal of the second reference voltage generation unit is connected to a non-inverting input terminal of the second comparator; the second reference voltage generating unit comprises a sixth resistor, a seventh resistor, an eighth resistor and a fourth diode; a first end of the sixth resistor is connected to a zero potential, and a second end of the sixth resistor is connected to an output end of the second reference voltage generation unit; the seventh resistor and the eighth resistor are connected in series between a high level and a zero potential; an anode of the fourth diode is connected to a connection point of the seventh resistor and the eighth resistor, and a cathode of the fourth diode is connected to a second end of the sixth resistor.
9. The maximum voltage comparison circuit of claim 8, wherein the sixth resistor and the second resistor have the same resistance value, and the fourth diode is of the same type as each of the second diodes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822066668.2U CN209946245U (en) | 2018-12-10 | 2018-12-10 | Voltage maximum value comparison circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822066668.2U CN209946245U (en) | 2018-12-10 | 2018-12-10 | Voltage maximum value comparison circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209946245U true CN209946245U (en) | 2020-01-14 |
Family
ID=69118775
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201822066668.2U Active CN209946245U (en) | 2018-12-10 | 2018-12-10 | Voltage maximum value comparison circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN209946245U (en) |
-
2018
- 2018-12-10 CN CN201822066668.2U patent/CN209946245U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8093878B2 (en) | Switching power supply device | |
| US20130265016A1 (en) | Direct Current Converter for Bootstrap Circuit | |
| CN101247081A (en) | Detection circuit and power source system | |
| US20180294635A1 (en) | Overcurrent protection device and vehicular electronic control unit | |
| CN109426296B (en) | Temperature sensor and method for detecting temperature | |
| KR102350085B1 (en) | Battery management system | |
| US9356471B2 (en) | Power supply circuit | |
| CN111693759A (en) | Voltage detector | |
| CN108880252B (en) | Linear constant current circuit | |
| CN209946245U (en) | Voltage maximum value comparison circuit | |
| US20160308450A1 (en) | Voltage conversion device | |
| CN112787505A (en) | DC-DC converter and control circuit and control method thereof | |
| CN213937415U (en) | Bus overcurrent protection circuit | |
| JP6658269B2 (en) | Overcurrent detection circuit | |
| CN112558680B (en) | Linear regulator and control circuit thereof | |
| CN210803575U (en) | High-side overcurrent detection circuit | |
| JP2009065809A (en) | Power conversion apparatus, and current detecting method thereof | |
| US9093961B2 (en) | Operational amplifier | |
| CN115275927A (en) | Short-circuit protection detection circuit and electronic product | |
| CN219659579U (en) | Voltage compensation circuit | |
| JP4941718B2 (en) | Voltage shift circuit | |
| JPH11160370A (en) | Abnormal voltage detection circuit | |
| CN216561568U (en) | Circuit for outputting stable voltage | |
| CN213754054U (en) | Built-in wire resistance compensation charging control circuit, power management chip and charging circuit | |
| JP2014062825A (en) | Voltage detection circuit, and voltage detection method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |