CN102122186B - High-power negative pressure numerical control constant current module - Google Patents
High-power negative pressure numerical control constant current module Download PDFInfo
- Publication number
- CN102122186B CN102122186B CN 201110033611 CN201110033611A CN102122186B CN 102122186 B CN102122186 B CN 102122186B CN 201110033611 CN201110033611 CN 201110033611 CN 201110033611 A CN201110033611 A CN 201110033611A CN 102122186 B CN102122186 B CN 102122186B
- Authority
- CN
- China
- Prior art keywords
- resistance
- operational amplifier
- numerical control
- negative pressure
- vmos
- 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
Landscapes
- Amplifiers (AREA)
Abstract
The invention discloses a high-power negative pressure numerical control constant current module, comprising a D/A (Digital/Analog) conversion chip, a photoelectronic isolator, an operational amplifier, a feedback unit and a VMOS (Vertical Metal Oxide Semiconductor) field effect transistor. An input digital signal is sequentially converted by the D/A conversion chip and the photoelectronic isolator and is then input to the positive phase terminal of the operational amplifier, the feedback unit feeds the grid voltage and the source voltage of the VMOS field effect transistor back to the negative phase terminal of the operational amplifier, and the operational amplifier outputs a control signal to the grid of the VMOS field effect transistor after comparison operation so as to control the drain of the VMOS field effect transistor to output a constant current. In the module provided by the invention, under the condition that the resolution of the input digital signal is 10 bits, an output current is varied in 1024 levels in the current range of 0-3A and the input control range of 0-1024 level digital signal, the initial voltage is more than or equal to minus 0.5V, the current stability is 9.9*10<-5>, the current temperature coefficient is 4.8*10<-5>, and the maximum power consumption is 30W.
Description
Technical field
The invention belongs to power asic technology field, relate in particular to a kind of high-power negative pressure numerical control constant flow module.
Background technology
The numerical control constant flow module under the irreplaceable condition of traditional constant current device, propose research, it be a kind of be the constant flow module of characteristic with the Digital Signals output current.It not only the output current adjustable extent wide, allow that the WV variation range is big, circuit interface and TTL compatible, and volume is little, easy to adjust, has good electrical property.Can be widely used in the technical field that traditional constant current device can't set foot in, in digital circuit technique is used, have special advantages.
Sheng Fasheng etc. disclose a kind of DCM02 type constant flow module (Sheng Fasheng; The model Arcam; The design analysis [J] of Lv Pin hardwood .DCM02 type numerical control constant current device. Hangzhou University's journal (natural science edition), 1997,24 (2): 125-132); This device bias voltage and TTL compatible have high-level efficiency, characteristics such as easy to use.
Sheng Fasheng etc. disclose a kind of numerical control constant current device (Sheng Fasheng, model Arcam, Bi Jing. a kind of high stability constant current device [J] that adopts Digital Signals. Chinese journal of scientific instrument; 1999,20 (3): 225-228), adopt modular construction; Low in energy consumption, volume is little, and has good electrical property.
The application of above-mentioned device is worked under the positive voltage situation, can not under the negative voltage situation, work, and not solve effective isolation of digital circuit part and artificial circuit part.
Summary of the invention
The invention provides that a kind of reliability is high, volume is little, low in energy consumption and the high-power negative pressure numerical control constant flow module of easy adjusting.
A kind of high-power negative pressure numerical control constant flow module; Comprise: D/A conversion chip, photoisolator, operational amplifier, feedback unit VMOS FET; The digital signal of input is the positive terminal of input operational amplifier after D/A conversion chip and photoisolator conversion successively; The negative phase end that feedback unit feeds back to operational amplifier with the grid voltage and the source voltage of VMOS FET; Output control signals to the grid of VMOS FET after the operational amplifier comparison operation, the drain electrode output steady current of control VMOS FET.
Described D/A conversion chip adopts the serial digital signal input, and external the tenth resistance carries out the linear correction of the first order.
Described photoisolator output terminal and operational amplifier positive terminal are provided with linear amending unit; Described linear amending unit is made up of second resistance, the 8th resistance, the 9th resistance and first resistance; The 9th resistance is parallelly connected with first resistance; Resistance after the parallel connection is connected with second resistance, and the resistance after the series connection is parallelly connected with the 8th resistance, and this amending unit carries out the linear correction in the second level to constant flow module.
Above-mentioned constant flow module also comprises the 7th resistance that connects VMOS FET source electrode, regulates the feedback voltage of the 5th resistance, the 6th resistance of concatenation operation amplifier out; The 6th resistance, the 7th resistance, first resistance, the 8th resistance and the 9th resistance are connected common junction.
Described feedback unit comprises the 4th resistance and the 5th resistance of parallel connection; The negative phase end of the 4th resistance and the common concatenation operation amplifier of the 5th resistance one end; The other end connects the grid and the drain electrode of VMOS FET respectively, and constant flow module is carried out the linear correction of the third level.
The present invention also provides the application of above-mentioned high-power negative pressure numerical control constant flow module in power integrated circuit.
Constant flow module of the present invention is through using photoisolator; Guarantee effective isolation of digital circuit and mimic channel; Used three grades of linear corrections simultaneously, first order correction is in the D/A change-over circuit, and the linearity of step pitch electric current and the high precision of D/A conversion are guaranteed in its linear correction; The linear correction in the second level is the linearity output after the assurance opto-electronic conversion, and it is that the linearity that guarantees the VMOS pipe is exported that the third level is revised.
The artificial circuit part of constant flow module of the present invention is worked under negative voltage, and starting potential is low, and the electric current adjustable extent is wide, circuit interface and TTL compatible, reliability is high, volume is little, low in energy consumption, be prone to regulate.This module can be applicable to computer control, robot, optical fiber communication, military equipment, aspects such as intelligent instrumentation and other robotization control.
Description of drawings
Fig. 1 is the modular structure figure of constant flow module of the present invention;
Fig. 2 is the circuit theory diagrams of galvanostat of the present invention;
Fig. 3 is the volt-ampere characteristics of figure of constant flow module of the present invention;
Fig. 4 is a constant flow module control signal sequential chart of the present invention;
Fig. 5 is constant flow module 10bit input of the present invention and output corresponding relation figure.
Embodiment
As shown in the figure, a kind of high-power negative pressure numerical control constant flow module comprises D/A conversion chip U1, photoisolator U2, operational amplifier A, feedback unit B and VMOS FET VT.The digital signal of input is changed the positive terminal of input operational amplifier A successively through D/A conversion chip U1, photoisolator U2; The negative phase end that feedback unit feeds back to operational amplifier A with grid voltage and the source voltage of VMOS FET VT; Output control signals to the grid of VMOS FET VT after the operational amplifier A comparison operation, the constant electric current of drain electrode output of control VMOS FET VT.
The D/A conversion chip adopts the serial digital-to-analog conversion, connects resistance R 10 outward and makes that the D/A reference power supply is adjustable.D/A conversion chip U1 is under the time clock effect; The digital signal of input is read in through shift register by turn; Import 10 clock period pulses at interval at two latch pulses; Latch 10 position digital signals and accomplish the D/A conversion, simulating signal after the D/A conversion and reference power supply compare back input photoisolator U2.
Connect linear amending unit between the output terminal of photoisolator U2 and the normal phase input end of operational amplifier A; This linearity amending unit is made up of resistance R 2, resistance R 8, resistance R 9 and resistance R 1; Wherein resistance R 1 is connected with resistance R 2 with the resistance of resistance R 9 parallel connections, and the resistance of series connection is parallelly connected with R8.Through the resistance of adjustment resistance R 9, make the output of photoisolator U2 keep linear change, resistance R 3 corresponding resistance R 1 are provided with the negative phase end of concatenation operation amplifier A.
Feedback unit adopts the amplification bleeder circuit that increases feedback, reduces power attenuation; It is made up of resistance R 4 and resistance R 5, and resistance R 4 two ends are negative phase end and the output terminal of concatenation operation amplifier A respectively, the negative phase end of resistance R 5 two ends difference concatenation operation amplifier A and the source electrode of VMOS FET VT.
VMOS FET VT is the N channel-type, has the impedance height, drive current is little, mutual conductance is big, conducting resistance is low and does not have advantages such as second breakdown, guarantees that the module output current is constant.
For making VMOS FET VT grid voltage stable, the output terminal connection resistance R 6 in operational amplifier A is the needs of feedback regulation, in the source electrode connection resistance R 7 of metal-oxide-semiconductor field effect transistor VT.Resistance R 7, resistance R 1, resistance R 6, resistance R 8 and resistance R 9 common ends are connected power supply Vss, and load Rf one end connects the drain electrode of VMOS FET VT, other end ground connection.Resistance R 7, resistance R 9 and resistance R 10 are adjustable resistance.
Fig. 3 is the drain electrode output volt-ampere characteristics of figure of VMOS FET VT; Work as on-load voltage greater than certain numerical value by scheming to find out; Output current is invariable all the time, does not change with load variations, and the resolution of output current depends on the input figure place of D/A conversion chip.
Fig. 5 is above-mentioned constant flow module 10bit input and output corresponding relation figure, shows present embodiment module output current I
0Variation with digital signal changes, and linear between the two.Contextual definition between its output current and the input of digital signal amount is:
I
0＝K.I
REF.D
2 (1)
I
0--module output current, D--binary digit amount, K--correction factor, I
REF--reference current, K wherein, I
REFAlso be that scale-of-two is converted into metric correction factor, formula (1) can be written as:
I
0＝K.I
REF.(a
02
0+a
12
1+......+a
m-12
m-1) (2)
With digital signal input resolution 10bit, maximum output current is that 3A is an example, K.I
REF=2.93, then by formula (2) the corresponding relation of digital quantity and analog quantity is:
I
0＝2.93(a
02
0+a
12
1+a
22
2+a
32
3+a
42
4+a
52
5+......+a
92
9)(mA) (3)
2.93mA is exactly the high-power negative pressure numerical control of a present embodiment constant flow module minimum controllable electric current in the formula (3); And accomplish that in force digital quantity is corresponding one by one with analog quantity; And maintenance high precision; Be that output current divides 1024 grades of variations in 0～1024 stages of digital signal input range of control in 0～3A scope, starting potential>=-0.5V, current stability, 9.9 * 10
-5, current temperature coefficient 4.8 * 10
-5, maximum power dissipation 30W (Zhejiang Province's electronic product check test 09/01/2001).
Claims (5)
1. high-power negative pressure numerical control constant flow module; It is characterized in that; Comprise D/A conversion chip (U1), photoisolator (U2), operational amplifier (A), feedback unit (B) and VMOS FET (VT); The digital signal of input is the positive terminal of input operational amplifier (A) after D/A conversion chip (U1) and photoisolator (U2) conversion successively; The negative phase end that feedback unit (B) feeds back to operational amplifier (A) with the grid voltage and the source voltage of VMOS FET (VT); Output control signals to the grid of VMOS FET (VT) after operational amplifier (A) comparison operation, thereby make the drain electrode output current of VMOS FET (VT) constant.
2. high-power negative pressure numerical control constant flow module according to claim 1 is characterized in that, described D/A conversion chip (U1) adopts the serial digital signal input.
3. high-power negative pressure numerical control constant flow module according to claim 1; It is characterized in that; Described photoisolator (U2) output terminal and operational amplifier (A) positive terminal are provided with linear amending unit; Described linear amending unit is made up of second resistance (R2), the 8th resistance (R8), the 9th resistance (R9) and first resistance (R1); The 9th resistance (R9) is parallelly connected with first resistance (R1), and the resistance after the parallel connection is connected with second resistance (R2), and the resistance after the series connection is parallelly connected with the 8th resistance (R8).
4. high-power negative pressure numerical control constant flow module according to claim 3 is characterized in that, comprises the 7th resistance (R7) that connects VMOS FET (VT) source electrode, the 6th resistance (R6) of concatenation operation amplifier (A) output terminal; The 6th resistance (R6), the 7th resistance (R7), first resistance (R1), the 8th resistance (R8) and the 9th resistance (R9) are connected common junction.
5. high-power negative pressure numerical control constant flow module according to claim 1; It is characterized in that; Described feedback unit is made up of the 4th resistance (R4) and the 5th resistance (R5); The negative phase end of the 4th resistance (R4) and the common concatenation operation amplifier of the 5th resistance (R5) end (A), the other end connect the grid and the drain electrode of VMOS FET (VT) respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110033611 CN102122186B (en) | 2011-01-31 | 2011-01-31 | High-power negative pressure numerical control constant current module |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110033611 CN102122186B (en) | 2011-01-31 | 2011-01-31 | High-power negative pressure numerical control constant current module |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102122186A CN102122186A (en) | 2011-07-13 |
| CN102122186B true CN102122186B (en) | 2012-12-26 |
Family
ID=44250756
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201110033611 Expired - Fee Related CN102122186B (en) | 2011-01-31 | 2011-01-31 | High-power negative pressure numerical control constant current module |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102122186B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106932684A (en) * | 2017-04-28 | 2017-07-07 | 方凤玲 | A kind of defeated glue trunnion electrical connection RTA reliability test assembly |
| CN109960303B (en) * | 2019-04-30 | 2024-08-23 | 深圳市明微电子股份有限公司 | Self-adaptive constant current control device |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201936214U (en) * | 2011-01-31 | 2011-08-17 | 浙江财经学院 | Large power negative pressure numerical control constant current module |
-
2011
- 2011-01-31 CN CN 201110033611 patent/CN102122186B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201936214U (en) * | 2011-01-31 | 2011-08-17 | 浙江财经学院 | Large power negative pressure numerical control constant current module |
Non-Patent Citations (2)
| Title |
|---|
| 盛法生,范雅俊,毕净.DCM02型数控恒流器件及其应用.《电子技术》.1999,(第1期),42-43. * |
| 盛法生,范雅俊,毕净.一种采用数字信号控制的高稳定性恒流器件.《仪器仪表学报》.1999,第20卷(第3期),225-228. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102122186A (en) | 2011-07-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105573391A (en) | Open-circuit voltage control circuit of solar array simulator and open-circuit voltage control method thereof | |
| CN110471484B (en) | Voltage reference source circuit and application thereof in shunt type I/F conversion circuit | |
| CN203552115U (en) | Output circuit of program-control current source | |
| CN102005941A (en) | Piezoelectric ceramics driving power supply for adjusting numerical control potentiometer | |
| CN104679084B (en) | Voltage calibration circuit and low pressure difference linearity voltage-stabilizing system | |
| CN102570895A (en) | Piezoceramic driving power supply | |
| CN101394183B (en) | A/D direct computing conversion, A/D cascade converter and use thereof | |
| CN102122186B (en) | High-power negative pressure numerical control constant current module | |
| CN103970173B (en) | Band-gap reference voltage circuit | |
| CN201867672U (en) | LDO (Low Dropout Regulator) circuit in mobile terminal | |
| CN201936214U (en) | Large power negative pressure numerical control constant current module | |
| CN207882786U (en) | A kind of programme control precision adjustable direct voltage source | |
| CN204883455U (en) | Programme -controlled adjustable export power supply's pressure regulating circuit | |
| CN103439905A (en) | IO input port expansion circuit | |
| CN202586751U (en) | High-precision AC/DC converter current-limiting circuit | |
| CN104219842A (en) | LED constant-current unit | |
| CN104731152A (en) | Positive and negative symmetrical output power source and medical device thereof | |
| CN102307011A (en) | Miniature high voltage isolation VV converter module formed by LM331 | |
| CN103647557A (en) | Analog-to-digital converter (ADC) circuit, electric energy metering circuit and electric energy metering system | |
| CN201063603Y (en) | True effective value converting circuit with low temperature drift | |
| CN101789686A (en) | Small high voltage isolated V/V converter module | |
| CN202453759U (en) | Bipolar reference voltage source device with driving function | |
| CN203930562U (en) | Band-gap reference voltage circuit | |
| CN103199824B (en) | A kind of staircase waveform circuit for generating | |
| CN102545907A (en) | Digital-analogue converter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20121226 Termination date: 20140131 |