CN202998050U - Current absolute value circuit - Google Patents
Current absolute value circuit Download PDFInfo
- Publication number
- CN202998050U CN202998050U CN 201220694624 CN201220694624U CN202998050U CN 202998050 U CN202998050 U CN 202998050U CN 201220694624 CN201220694624 CN 201220694624 CN 201220694624 U CN201220694624 U CN 201220694624U CN 202998050 U CN202998050 U CN 202998050U
- Authority
- CN
- China
- Prior art keywords
- resistance
- diode
- absolute value
- operational amplifier
- input
- 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.)
- Expired - Fee Related
Links
Images
Abstract
The utility model discloses a current absolute value circuit which comprises a rectifier bridge and a differential amplification circuit which is composed of resistors and operational amplifiers. Input current is rectified into direct current by the rectifier bridge and is output after being changed from double-end to single-end through the differential amplification circuit so as to make the value of output voltage the absolute value of the input current. The utility model further discloses a driving method for the current absolute value circuit. The advantages are as follows: the number of the operational amplifiers can be effectively reduced, the value of the output voltage can be the absolute value of the input current, and the like.
Description
Technical field
The present invention relates to processing data information circuit engineering field, be specifically related to a kind of electric current absolute value circuit.
Background technology
Absolute value circuit is a kind of circuit of the number of winning the confidence absolute value, and namely its output signal is the absolute value of input signal or proportional with this absolute value.Common has following two schemes with improved absolute value circuit.
As shown in Figure 1, it is common absolute value circuit.When port one 3 input positive signal, operational amplifier 15 output negative voltages cause diode 17 conductings, diode 18 cut-offs, and the output voltage of operational amplifier 16 is determined jointly by resistance 21, resistance 23, resistance 24, resistance 25; When port one input negative polarity signal, operational amplifier 15 output positive voltages cause diode 17 cut-offs, diode 18 conductings, and the output voltage of operational amplifier 16 is determined jointly by resistance 21, resistance 22, resistance 23, resistance 24 and resistance 25.The shortcoming of this scheme is, is not suitable for realizing the absolute value of electric current.
As shown in Figure 2, be disclosed a kind of broadband low-error absolute value circuit in the Chinese patent of application number CN200420091345.4.When port one 4 input positive signal, operational amplifier is owing to adopting single supply Vcc (positive supply) power supply, so operational amplifier 26 cut-off, operational amplifier 27 work, the output of port 30 is determined through the dividing potential drop of resistance 28 and resistance 29 by the output voltage of operational amplifier 27; In like manner, when port one input negative polarity signal, operational amplifier 26 work, operational amplifier 27 cut-offs, the output of port 30 is determined through the dividing potential drop of resistance 28 and resistance 29 by the output voltage of operational amplifier 26.The shortcoming of this scheme is, output voltage will be considered load to the impact of the dividing potential drop of resistance 28 and resistance 29, and is not suitable for realizing the absolute value of electric current.
Summary of the invention
The shortcoming that one of purpose of the present invention is to overcome prior art provides a kind of circuit of being convenient to realize the current signal absolute value function with not enough, and its output voltage is directly proportional to the absolute value of input current signal.
The shortcoming that two of purpose of the present invention is to overcome prior art provides a kind of circuit drive method of being convenient to realize the current signal absolute value function with not enough.
For realizing that the technical scheme that one of purpose of the present invention adopts is: a kind of electric current absolute value circuit comprises input port, rectifier bridge, the first resistance, differential amplifier circuit and output port; Described rectifier bridge comprises the first diode, the second diode, the 3rd diode and the 4th diode; Wherein the anode of the first diode is connected with input port, the anode of the second diode with reference to ground be connected, the negative electrode of the 3rd diode is connected with input port, the negative electrode of the 4th diode with reference to ground be connected, the negative electrode of the first diode is connected with the negative electrode of the second diode, the anodic bonding of the anode of the 3rd diode and the 4th diode, the first resistance are connected between the anode of the negative electrode of the second diode and the 4th diode; Described differential amplifier circuit comprises the first operational amplifier, the second resistance, the 3rd resistance, the 4th resistance and the 5th resistance, and the second resistance equates with the 4th resistance, and the 3rd resistance equates with the 5th resistance; Wherein the second resistance is connected between the in-phase input end of the negative electrode of the second diode and the first operational amplifier, the 3rd resistance is connected to the in-phase input end of the first operational amplifier and with reference between ground, the 4th resistance is connected between the inverting input of the anode of the 4th diode and the first operational amplifier, the 5th resistance is connected between the inverting input and output port of the first operational amplifier, and the output of the first operational amplifier is connected with output port.
For realizing that the technical scheme that two of purpose of the present invention adopts is: a kind of driving method of electric current absolute value circuit comprises the steps:
Step 1, input current are direct current through the rectifier bridge rectification;
Step 2, make direct current after rectification first resistance of flowing through, the direct voltage that produces on the first resistance is directly proportional to the absolute value of input current;
If input current is i, the output of the differential amplifier circuit i.e. output voltage of the first operational amplifier is Vo, the first resistance is R1, the second, four resistances equate and equal R2, three, five resistances equate and equal R3, Vo ≈ ∣ i ∣ * R1 * (R3/R2), the accuracy of this formula depends on the output current of rectifier bridge first resistance of whether all flowing through, therefore R2 and R3 should be large as far as possible, thereby reduce second and third, four, five resistance are to the shunting action of first resistor current of flowing through.
Preferably, described the first resistance is got 1 Ω, gets second and third, four, five resistances equate and equal 100K Ω, Vo ≈ ∣ i ∣.
Compared with prior art, the present invention has following advantage and beneficial effect:
(1) the present invention be directed to and be input as current signal and propose, be used for realizing that output voltage is proportional to the absolute value of input current, prior art is only suitable in realizing that output voltage is proportional to the absolute value of input voltage for being input as voltage signal.
(2) the present invention adopts rectifier bridge rather than obtains the input current absolute value by operational amplifier, and its advantage is to have avoided the problem of operational amplifier lag output in input, and therefore applicable frequency is higher.
(3) symmetry is good, the present invention realizes the absolute value function of input current by rectifier bridge, rectifier bridge output DC stream equates fully with the absolute value of input current, orientation independent with input current, and in the absolute value circuit that adopts prior art, input voltage signal polarity is different, and the transmission path in circuit is also different, therefore is difficult to guarantee that the opposite voltage signal of big or small identical polar is identical at the absolute value of output.
Description of drawings
Fig. 1 is a kind of common absolute value circuit figure in prior art
Fig. 2 is the low error absolute value circuit figure of a kind of frequency band in prior art
Fig. 3 is electric current absolute value circuit figure of the present invention
Fig. 4 is the flow process frame diagram of circuit drive method of the present invention
Embodiment
The present invention is described in further detail below in conjunction with embodiment and accompanying drawing, but embodiments of the present invention are not limited to this.
As shown in Figure 3, the electric current absolute value circuit comprises input port, rectifier bridge, the first resistance, differential amplifier circuit and output port.
Described rectifier bridge comprises the first diode 2, the second diode 3, the 3rd diode 4, the 4th diode 5; Wherein the anode of the first diode 2 is connected with input port 1, the anode of the second diode 3 with reference to ground be connected, the negative electrode of the 3rd diode 4 is connected with input port 1, the negative electrode of the 4th diode 5 with reference to ground be connected, the negative electrode of the first diode 2 is connected with the negative electrode of the second diode 3, the anodic bonding of the anode of the 3rd diode 4 and the 4th diode 5, the first resistance 6 are connected between the anode of the negative electrode of the second diode 3 and the 4th diode 5.
Described differential amplifier circuit comprises the first operational amplifier 11, the second resistance 7, the 3rd resistance 8, the 4th resistance 9 and the 5th resistance 10, and the second resistance 7 equates with the 4th resistance 9 resistances, and the 3rd resistance 8 equates with the 5th resistance 10 resistances; Wherein the second resistance 7 is connected between the in-phase input end of the negative electrode of the second diode 3 and the first operational amplifier 11, the 3rd resistance 8 is connected to the in-phase input end of the first operational amplifier 11 and with reference between ground, the 4th resistance 9 is connected between the inverting input of the anode of the 4th diode 5 and the first operational amplifier 11, the 5th resistance 10 is connected between the inverting input and output port 12 of the first operational amplifier 11, and the output of the first operational amplifier is connected with output port 12.The first operational amplifier 11 adopts duplicate supplys, namely Vcc (positive supply) and-the Vcc(negative supply) power.
As shown in Figure 4, the process control chart of circuit drive method of the present invention: input current is transformed to direct current and flows through resistance 6 through after rectifier bridge, the voltage that produces on resistance 6 like this is proportional to the absolute value of input current, and the voltage on resistance 6 is exported at output port 12 with between with reference to ground after the change of differential amplifier circuit both-end is single-ended.
Above-described embodiment is the better execution mode of the present invention; but embodiments of the present invention are not restricted to the described embodiments; other any do not deviate from change, the modification done under Spirit Essence of the present invention and principle, substitutes, combination, simplify; all should be the substitute mode of equivalence, within being included in protection scope of the present invention.
Claims (2)
1. an electric current absolute value circuit, is characterized in that: comprise input port (1), rectifier bridge, the first resistance (6), differential amplifier circuit and output port;
Described rectifier bridge comprises the first diode (2), the second diode (3), the 3rd diode (4), the 4th diode (5); Wherein the anode of the first diode (2) is connected with input port (1), the anode of the second diode (3) with reference to ground be connected, the negative electrode of the 3rd diode (4) is connected with input port (1), the negative electrode of the 4th diode (5) with reference to ground be connected, the negative electrode of the first diode (2) is connected with the negative electrode of the second diode (3), the anodic bonding of the anode of the 3rd diode (4) and the 4th diode (5).
2. electric current absolute value circuit according to claim 1, it is characterized in that, described differential amplifier circuit comprises the first operational amplifier (11), the second resistance (7), the 3rd resistance (8), the 4th resistance (9) and the 5th resistance (10), and the second resistance (7) equates with the 4th resistance (9) resistance, and the 3rd resistance (8) equates with the 5th resistance (10) resistance, wherein the first resistance (6) is connected between the anode of the negative electrode of the second diode (3) and the 4th diode (5), the second resistance (7) is connected between the in-phase input end of the negative electrode of the second diode (3) and the first operational amplifier (11), the 3rd resistance (8) is connected to the in-phase input end of the first operational amplifier (11) and with reference between ground, the 4th resistance (9) is connected between the inverting input of the anode of the 4th diode (5) and the first operational amplifier (11), the 5th resistance (10) is connected between the inverting input and output port (12) of the first operational amplifier (11), the output of the first operational amplifier is connected with output port (12).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220694624 CN202998050U (en) | 2012-12-16 | 2012-12-16 | Current absolute value circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220694624 CN202998050U (en) | 2012-12-16 | 2012-12-16 | Current absolute value circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202998050U true CN202998050U (en) | 2013-06-12 |
Family
ID=48569175
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220694624 Expired - Fee Related CN202998050U (en) | 2012-12-16 | 2012-12-16 | Current absolute value circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202998050U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103066983A (en) * | 2012-12-16 | 2013-04-24 | 华南理工大学 | Current absolute value circuit and drive method thereof |
| CN109002739A (en) * | 2017-06-07 | 2018-12-14 | 北京普源精电科技有限公司 | A kind of absolute value circuit |
-
2012
- 2012-12-16 CN CN 201220694624 patent/CN202998050U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103066983A (en) * | 2012-12-16 | 2013-04-24 | 华南理工大学 | Current absolute value circuit and drive method thereof |
| CN109002739A (en) * | 2017-06-07 | 2018-12-14 | 北京普源精电科技有限公司 | A kind of absolute value circuit |
| CN109002739B (en) * | 2017-06-07 | 2020-03-17 | 北京普源精电科技有限公司 | Absolute value circuit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103309387B (en) | Voltage regulator | |
| CN105242734B (en) | A kind of high power LD O circuit without external electric capacity | |
| CN208848104U (en) | A kind of low pressure difference linear voltage regulator of fast transient response | |
| CN202548685U (en) | Reference voltage buffer circuit | |
| CN103323653B (en) | A kind of low limit sample circuit | |
| CN104283546A (en) | Low-voltage differential signal driver | |
| CN202998050U (en) | Current absolute value circuit | |
| CN104579260B (en) | Hysteresis comparator for radio frequency identification | |
| CN103066983A (en) | Current absolute value circuit and drive method thereof | |
| CN203457116U (en) | CMFB differential amplification circuit and integrated circuit | |
| CN103217615A (en) | Output short-circuit detection circuit | |
| CN203069764U (en) | Electric parameter measurement circuit of battery pack | |
| CN104811181A (en) | Current-to-voltage conversion circuit with input bias and active power filtering effects and current-to-voltage conversion method | |
| CN105652070B (en) | A kind of differential signal amplitude detection circuit | |
| CN204206141U (en) | A kind of MLVDS driver with constant differential output voltage | |
| CN105228287B (en) | Line voltage compensation circuit and LED illumination circuit for LED illumination | |
| CN108227812A (en) | A kind of high stability high precision current source circuit | |
| CN103424598B (en) | Inversion system output voltage detecting circuit and inversion system | |
| CN202903932U (en) | Anti-interference three-state input detection circuit with low power consumption | |
| CN203423834U (en) | LED drive circuit and transconductance amplifier thereof. | |
| CN206759414U (en) | Single-ended analog input interface circuit | |
| CN205510010U (en) | Self -adaptation mains voltage's RS -485 input common mode range expander circuit | |
| CN101902215A (en) | Four-input terminal comparator | |
| CN206471808U (en) | One kind is used for motor-driven high-end over-current protection circuit topological structure | |
| CN207115228U (en) | A kind of servo drive control feedback circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130612 Termination date: 20151216 |
|
| EXPY | Termination of patent right or utility model |