CN205178927U - Stepping motor driving circuit - Google Patents
Stepping motor driving circuit Download PDFInfo
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- CN205178927U CN205178927U CN201521052643.7U CN201521052643U CN205178927U CN 205178927 U CN205178927 U CN 205178927U CN 201521052643 U CN201521052643 U CN 201521052643U CN 205178927 U CN205178927 U CN 205178927U
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Abstract
The utility model discloses a stepping motor driving circuit, including controller, stepping motor driving circuit and the step motor who connects gradually to reach the timing circuit who meets with the controller, stepping motor driving circuit's figure is a plurality of, and every stepping motor driving circuit is all including the comparator, trigger, buffer circuit and the drive circuit that connect gradually to reach the electric current bleeder circuit and the signal feedback circuit that meet with the drive circuit output, signal feedback circuit meets with the input of comparator including the current sampling circuit, buffer and the operational amplifier that connect gradually, operational amplifier's output, and current sampling circuit's input and step motor's input all meet with the drive circuit output, and the input of comparator and the input of trigger all meet with the output of controller, the utility model relates to a novelty, electrical isolation between controller and the step motor has the good electric current function of releasing, and feedback mode control precision is high, and the practicality is strong.
Description
Technical field
The utility model belongs to Design of Stepper Motor Control Circuit field, is specifically related to a kind of stepper motor driving circuit.
Background technology
Stepping motor is opened loop control unit stepping motor part electric impulse signal being changed into angular displacement or displacement of the lines, when non-overload, the rotating speed of motor, frequency and the umber of pulse of pulse signal are only depended in the position stopped, and not by the impact of load variations, stepping motor can be divided into two-phase stepper motor with the number of phases, three-phase stepper motor, four phase step motor, five phase step motor etc., stepping motor in use each phase all needs drive singal, existing stepper motor driver is all encapsulated in less space, and electromagnetic environment is very severe during driving stepper motor, it is alternate with interior interference phenomenon is comparatively serious mutually, secondly, it is severe that stepping motor coil can vibrate when stopping drives suddenly, electric current sharply increases heating, and power consumption is increased, in addition, each phase drive singal many employings open loop type of drive of stepping motor, controls unstable, poor reliability, therefore, nowadays the stepper motor driving circuit that a kind of structure is simple, volume is little, cost is low, reasonable in design is lacked, each phase drive singal for stepping motor all adopts buffer circuit and isolated amplifier to make to realize electric isolution between driving stepper motor input signal and stepping motor, avoid stepping motor alternate with mutually in mutually interference, by arranging first-grade protection circuit after the drive circuit of each phase of stepping motor, reducing coil vibration and coil heating severity, reducing power consumption, meanwhile, each phase drive singal of stepping motor all adopts closed loop feedback type of drive, and effectively control each phase drive singal by current sample, changing voltage and voltage compare reliable and stable, precision is high.
Utility model content
Technical problem to be solved in the utility model is for above-mentioned deficiency of the prior art, a kind of stepper motor driving circuit is provided, it is rationally novel in design, structure is simple, employing buffer circuit and isolated amplifier realize the electric isolution between controller and stepping motor, and have good current drain function, feedback model control precision is high, practical, be convenient to promote the use of.
For solving the problems of the technologies described above, the technical solution adopted in the utility model is: a kind of stepper motor driving circuit, it is characterized in that: comprise the controller, stepper motor driving circuit and the stepping motor that connect successively, and the timing circuit connected with described controller; The number of described stepper motor driving circuit is multiple, each described stepper motor driving circuit includes the comparator, trigger, buffer circuit and the drive circuit that connect successively, and the first-grade protection circuit connected with described drive circuit output and signal feedback circuit; Described signal feedback circuit comprises the current sampling circuit, isolated amplifier and the operational amplifier that connect successively, the output of described operational amplifier connects with the input of comparator, the input of described current sampling circuit and the input of described stepping motor all connect with the output of drive circuit, the input of described comparator and the input of described trigger all connect with the output of controller, and described timing circuit comprises timing chip DS1302.
Above-mentioned a kind of stepper motor driving circuit, it is characterized in that: described comparator comprises amplifier U1, the in-phase input end of described amplifier U1 connects with controller through resistance R3, and the output of amplifier U1 divides two-way, one tunnel connects with 5V power supply through resistance R2, and another road is the signal output part of comparator.
Above-mentioned a kind of stepper motor driving circuit, it is characterized in that: described trigger comprises d type flip flop U2, the CIR pin of described d type flip flop U2 connects with the signal output part of comparator, the CLK pin of d type flip flop U2 connects with controller, and the D pin of d type flip flop U2, SD pin and VCC pin all connect with 5V power supply.
Above-mentioned a kind of stepper motor driving circuit, is characterized in that: described buffer circuit comprises isolating chip U3, and the 1st pin of described isolating chip U3 connects with the Q pin of d type flip flop U2, and the 4th pin of isolating chip U3 connects with 5V power supply.
Above-mentioned a kind of stepper motor driving circuit, it is characterized in that: described drive circuit comprises Darlington transistor Q1 and triode Q2, first pole of described Darlington transistor Q1 connects with the 3rd pin of isolating chip U3 through resistance R4, second pole of Darlington transistor Q1 connects with the base stage of triode Q2, and the link of the 3rd pole of Darlington transistor Q1 and the collector electrode of triode Q2 is the signal output part of drive circuit.
Above-mentioned a kind of stepper motor driving circuit, it is characterized in that: described first-grade protection circuit comprises diode D1, inductance L 1, electric capacity C1, electric capacity C2 and resistance R1, the anode of described diode D1 connects with one end of inductance L 1, the anode of diode D1 and the link of one end of inductance L 1 connect with the signal output part of drive circuit, the negative electrode of diode D1 connects with one end of resistance R1 in parallel and electric capacity C2, resistance R1 in parallel and the other end of electric capacity C2 divide two-way, one tunnel connects with the other end of inductance L 1, and another road is through electric capacity C1 ground connection.
Above-mentioned a kind of stepper motor driving circuit, is characterized in that: described current sampling circuit comprises precision resistance R10, and one end of described precision resistance R10 connects with the emitter of triode Q2, the other end ground connection of precision resistance R10.
Above-mentioned a kind of stepper motor driving circuit, it is characterized in that: described isolated amplifier comprises isolated amplifier HCPL-7800, the Vin+ pin of described isolated amplifier HCPL-7800 connects with the link of one end of precision resistance R10 and the emitter of triode Q2 through resistance R8, the Vin-pin ground connection of isolated amplifier HCPL-7800, VDD1 pin and the VDD2 pin of isolated amplifier HCPL-7800 all connect with 5V power supply.
Above-mentioned a kind of stepper motor driving circuit, it is characterized in that: described operational amplifier comprises amplifier U4, the in-phase input end of described amplifier U4 connects with the Vout+ pin of isolated amplifier HCPL-7800 through resistance R9, the inverting input of amplifier U4 divides two-way, one tunnel is through resistance R13 ground connection, and another road connects with the Vout-pin of isolated amplifier HCPL-7800 through resistance R12; The output of amplifier U4 divides two-way, and a road connects with the link of the Vout+ pin of resistance R9 and isolated amplifier HCPL-7800 through resistance R7, and another road connects with the inverting input of amplifier U1 through resistance R11.
The utility model compared with prior art has the following advantages:
1, the utility model is by arranging buffer circuit, realizes low voltage control end and drives high pressure stepping motor output, avoid alternate with mutually in interference; By arranging isolated amplifier, realizing high pressure stepping motor output end signal and feeding back to low voltage control end, strong interference immunity, controlling reliable and stable; Realize the electric isolution between controller and stepping motor, cut off the passage of interference signal, circuit is simple, is convenient to promote the use of.
2, the utility model is by arranging comparator and trigger, when controller Setting signal is constant, comparator is by comparison signal feedback circuit and controller Setting signal, when the signal feedback circuit voltage signal gathered is lower than controller Setting signal, amplifier U1 in comparator exports high level, controller control trigger makes trigger export high level, and buffer circuit conducting drives triode Q2 conducting Driving Stepping Motor coil current to raise; When the signal feedback circuit voltage signal gathered is close to controller Setting signal, comparator is in critical rollover states, and stepping motor coil current maintains the upper and lower small variations of this critical value and mean value is constant, and reliable and stable, result of use is good.
3, the utility model is by arranging first-grade protection circuit, when controller Setting signal stops suddenly driving, adopts the leadage circuit of diode, resistance, electric capacity and inductance composition, reduces coil vibration and coil heating severity, reduces power consumption.
4, the utility model is rationally novel in design, and volume is little, and control precision is high, practical, is convenient to promote the use of.
In sum, the utility model is rationally novel in design, and structure is simple, employing buffer circuit and isolated amplifier realize the electric isolution between controller and stepping motor, and have good current drain function, feedback model control precision is high, practical, be convenient to promote the use of.
Below by drawings and Examples, the technical solution of the utility model is described in further detail.
Accompanying drawing explanation
Fig. 1 is circuit block diagram of the present utility model.
Fig. 2 is schematic block circuit diagram of the present utility model (not shown timing circuit).
Fig. 3 is the circuit theory diagrams of the utility model stepper motor driving circuit.
Description of reference numerals:
1-controller; 2-timing circuit; 3-stepper motor driving circuit;
3-1-comparator; 3-2-trigger; 3-3-buffer circuit;
3-4-drive circuit; 3-5-first-grade protection circuit; 3-6-current sampling circuit;
3-7-isolated amplifier; 3-8-operational amplifier; 4-stepping motor.
Embodiment
As depicted in figs. 1 and 2, the utility model comprises the controller 1, stepper motor driving circuit 3 and the stepping motor 4 that connect successively, and the timing circuit 2 connected with described controller 1; The number of described stepper motor driving circuit 3 is multiple, each described stepper motor driving circuit 3 includes the comparator 3-1, trigger 3-2, buffer circuit 3-3 and the drive circuit 3-4 that connect successively, and the first-grade protection circuit 3-5 connected with described drive circuit 3-4 output and signal feedback circuit; Described signal feedback circuit comprises the current sampling circuit 3-6, isolated amplifier 3-7 and the operational amplifier 3-8 that connect successively, the output of described operational amplifier 3-8 connects with the input of comparator 3-1, the input of described current sampling circuit 3-6 and the input of described stepping motor 4 all connect with the output of drive circuit 3-4, the input of described comparator 3-1 and the input of described trigger 3-2 all connect with the output of controller 1, and described timing circuit 2 comprises timing chip DS1302.
It should be noted that, described stepping motor 4 comprises two-phase stepper motor, three-phase stepper motor, four phase step motor or five phase step motor, the number of described stepper motor driving circuit 3 is identical with keeping count of mutually of used stepping motor, each phase coil corresponding in multiple motor-drive circuit 3 difference Driving Stepping Motor, use timing circuit 2 that the phase sequence of multiple motor-drive circuit 3 is set in advance, multiple motor-drive circuit 3 is all connected with controller 1, and the phase sequence that timing circuit 2 arranges multiple motor-drive circuit 3 in advance exports by controller 1.
As shown in Figure 3, in the present embodiment, described comparator 3-1 comprises amplifier U1, the in-phase input end of described amplifier U1 connects with controller 1 through resistance R3, the output of amplifier U1 divides two-way, and a road connects with 5V power supply through resistance R2, and another road is the signal output part of comparator 3-1.
As shown in Figure 3, in the present embodiment, described trigger 3-2 comprises d type flip flop U2, and the CIR pin of described d type flip flop U2 connects with the signal output part of comparator 3-1, the CLK pin of d type flip flop U2 connects with controller 1, and the D pin of d type flip flop U2, SD pin and VCC pin all connect with 5V power supply.
As shown in Figure 3, in the present embodiment, described buffer circuit 3-3 comprises isolating chip U3, and the 1st pin of described isolating chip U3 connects with the Q pin of d type flip flop U2, and the 4th pin of isolating chip U3 connects with 5V power supply.
As shown in Figure 3, in the present embodiment, described drive circuit 3-4 comprises Darlington transistor Q1 and triode Q2, first pole of described Darlington transistor Q1 connects with the 3rd pin of isolating chip U3 through resistance R4, second pole of Darlington transistor Q1 connects with the base stage of triode Q2, and the link of the 3rd pole of Darlington transistor Q1 and the collector electrode of triode Q2 is the signal output part of drive circuit 3-4.
As shown in Figure 3, in the present embodiment, described first-grade protection circuit 3-5 comprises diode D1, inductance L 1, electric capacity C1, electric capacity C2 and resistance R1, the anode of described diode D1 connects with one end of inductance L 1, the link of the anode of diode D1 and one end of inductance L 1 connects with the signal output part of drive circuit 3-4, the negative electrode of diode D1 connects with one end of resistance R1 in parallel and electric capacity C2, resistance R1 in parallel and the other end of electric capacity C2 divide two-way, one tunnel connects with the other end of inductance L 1, and another road is through electric capacity C1 ground connection.
As shown in Figure 3, in the present embodiment, described current sampling circuit 3-6 comprises precision resistance R10, and one end of described precision resistance R10 connects with the emitter of triode Q2, the other end ground connection of precision resistance R10.
As shown in Figure 3, in the present embodiment, described isolated amplifier 3-7 comprises isolated amplifier HCPL-7800, the Vin+ pin of described isolated amplifier HCPL-7800 connects with the link of one end of precision resistance R10 and the emitter of triode Q2 through resistance R8, the Vin-pin ground connection of isolated amplifier HCPL-7800, VDD1 pin and the VDD2 pin of isolated amplifier HCPL-7800 all connect with 5V power supply.
As shown in Figure 3, in the present embodiment, described operational amplifier 3-8 comprises amplifier U4, the in-phase input end of described amplifier U4 connects with the Vout+ pin of isolated amplifier HCPL-7800 through resistance R9, the inverting input of amplifier U4 divides two-way, one tunnel is through resistance R13 ground connection, and another road connects with the Vout-pin of isolated amplifier HCPL-7800 through resistance R12; The output of amplifier U4 divides two-way, and a road connects with the link of the Vout+ pin of resistance R9 and isolated amplifier HCPL-7800 through resistance R7, and another road connects with the inverting input of amplifier U1 through resistance R11.
When the utility model uses, selected stepping motor 4 type, correspondence arranges the number of stepper motor driving circuit 3, keep the number of stepper motor driving circuit 3 identical with keeping count of mutually of selected stepping motor 4, adopt the timing chip DS1302 in timing circuit 2 that each phase activation schedule in stepping motor 4 is set in advance, and exported by controller 1, multiple stepper motor driving circuit 3 is connected on each phase coil of stepping motor 4, controller 1 exports a Setting signal to successively the comparator 3-1 in each stepper motor driving circuit 3, under initial state, coil current in stepping motor 4 is 0, current sampling circuit 3-6 does not collect current data, in comparator 3-1, the anti-phase input terminal voltage of amplifier U1 is 0, the in-phase input end of amplifier U1 is higher than the inverting input of amplifier U1, comparator 3-1 exports high level, controller 1 drives trigger 2 to make d type flip flop U2 export high level buffer circuit 3-3 conducting, Islington pipe Q1 in drive circuit 3-4 and triode Q2 conducting, coil electricity generation current in stepping motor 4, current sampling circuit 3-6 sampling coil current data is input to the inverting input of amplifier U1 in comparator 3-1 after isolated amplifier 3-7 and operational amplifier 3-8 amplifies, in comparator 3-1, the anti-phase input terminal voltage of amplifier U1 increases gradually, when amplifier U1 in the anti-phase input terminal voltage and comparator 3-1 of amplifier U1 in comparator 3-1 in-phase input end voltage close to time, comparator 3-1 is in critical rollover states, when the in-phase input end voltage of amplifier U1 during the anti-phase input terminal voltage of amplifier U1 in comparator 3-1 is higher than comparator 3-1, amplifier U1 output low level, drive circuit 3-4 ends, the output that current sampling circuit 3-6 gathers reduces, circulation like this, stepping motor coil maintains that a critical value perturbs up and down and mean value is constant, therefore the object that the large I of comparator 3-1 input signal reaches control step current of electric is changed, thus reach the object controlling motor speed, when controller 1 Setting signal stops suddenly driving, adopt first-grade protection circuit 3-5 leakage current, reduce the vibration of stepping motor coil and coil heating severity, reduce power consumption, circuit is reliable.
The above; it is only preferred embodiment of the present utility model; not the utility model is imposed any restrictions; every above embodiment is done according to the utility model technical spirit any simple modification, change and equivalent structure change, all still belong in the protection range of technical solutions of the utility model.
Claims (9)
1. a stepper motor driving circuit, it is characterized in that: comprise the controller (1), stepper motor driving circuit (3) and the stepping motor (4) that connect successively, and the timing circuit (2) connected with described controller (1), the number of described stepper motor driving circuit (3) is multiple, each described stepper motor driving circuit (3) includes the comparator (3-1), trigger (3-2), buffer circuit (3-3) and the drive circuit (3-4) that connect successively, and the first-grade protection circuit (3-5) connected with described drive circuit (3-4) output and signal feedback circuit, described signal feedback circuit comprises the current sampling circuit (3-6) connected successively, isolated amplifier (3-7) and operational amplifier (3-8), the output of described operational amplifier (3-8) connects with the input of comparator (3-1), the input of described current sampling circuit (3-6) and the input of described stepping motor (4) all connect with the output of drive circuit (3-4), the input of described comparator (3-1) and the input of described trigger (3-2) all connect with the output of controller (1), described timing circuit (2) comprises timing chip DS1302.
2. according to a kind of stepper motor driving circuit according to claim 1, it is characterized in that: described comparator (3-1) comprises amplifier U1, the in-phase input end of described amplifier U1 connects with controller (1) through resistance R3, the output of amplifier U1 divides two-way, one tunnel connects with 5V power supply through resistance R2, and another road is the signal output part of comparator (3-1).
3. according to a kind of stepper motor driving circuit according to claim 2, it is characterized in that: described trigger (3-2) comprises d type flip flop U2, the CIR pin of described d type flip flop U2 connects with the signal output part of comparator (3-1), the CLK pin of d type flip flop U2 connects with controller (1), and the D pin of d type flip flop U2, SD pin and VCC pin all connect with 5V power supply.
4. according to a kind of stepper motor driving circuit according to claim 3, it is characterized in that: described buffer circuit (3-3) comprises isolating chip U3,1st pin of described isolating chip U3 connects with the Q pin of d type flip flop U2, and the 4th pin of isolating chip U3 connects with 5V power supply.
5. according to a kind of stepper motor driving circuit according to claim 4, it is characterized in that: described drive circuit (3-4) comprises Darlington transistor Q1 and triode Q2, first pole of described Darlington transistor Q1 connects with the 3rd pin of isolating chip U3 through resistance R4, second pole of Darlington transistor Q1 connects with the base stage of triode Q2, and the link of the 3rd pole of Darlington transistor Q1 and the collector electrode of triode Q2 is the signal output part of drive circuit (3-4).
6. according to a kind of stepper motor driving circuit according to claim 5, it is characterized in that: described first-grade protection circuit (3-5) comprises diode D1, inductance L 1, electric capacity C1, electric capacity C2 and resistance R1, the anode of described diode D1 connects with one end of inductance L 1, the link of the anode of diode D1 and one end of inductance L 1 connects with the signal output part of drive circuit (3-4), the negative electrode of diode D1 connects with one end of resistance R1 in parallel and electric capacity C2, resistance R1 in parallel and the other end of electric capacity C2 divide two-way, one tunnel connects with the other end of inductance L 1, another road is through electric capacity C1 ground connection.
7. according to a kind of stepper motor driving circuit according to claim 5, it is characterized in that: described current sampling circuit (3-6) comprises precision resistance R10, one end of described precision resistance R10 connects with the emitter of triode Q2, the other end ground connection of precision resistance R10.
8. according to a kind of stepper motor driving circuit according to claim 7, it is characterized in that: described isolated amplifier (3-7) comprises isolated amplifier HCPL-7800, the Vin+ pin of described isolated amplifier HCPL-7800 connects with the link of one end of precision resistance R10 and the emitter of triode Q2 through resistance R8, the Vin-pin ground connection of isolated amplifier HCPL-7800, VDD1 pin and the VDD2 pin of isolated amplifier HCPL-7800 all connect with 5V power supply.
9. according to a kind of stepper motor driving circuit according to claim 8, it is characterized in that: described operational amplifier (3-8) comprises amplifier U4, the in-phase input end of described amplifier U4 connects with the Vout+ pin of isolated amplifier HCPL-7800 through resistance R9, the inverting input of amplifier U4 divides two-way, one tunnel is through resistance R13 ground connection, and another road connects with the Vout-pin of isolated amplifier HCPL-7800 through resistance R12; The output of amplifier U4 divides two-way, and a road connects with the link of the Vout+ pin of resistance R9 and isolated amplifier HCPL-7800 through resistance R7, and another road connects with the inverting input of amplifier U1 through resistance R11.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201521052643.7U CN205178927U (en) | 2015-12-16 | 2015-12-16 | Stepping motor driving circuit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201521052643.7U CN205178927U (en) | 2015-12-16 | 2015-12-16 | Stepping motor driving circuit |
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| CN205178927U true CN205178927U (en) | 2016-04-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201521052643.7U Active CN205178927U (en) | 2015-12-16 | 2015-12-16 | Stepping motor driving circuit |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110261658A (en) * | 2019-06-21 | 2019-09-20 | 卡瓦科尔牙科医疗器械（苏州）有限公司 | A kind of medical instrument sample circuit structure and the method for sampling for isolation detection |
-
2015
- 2015-12-16 CN CN201521052643.7U patent/CN205178927U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110261658A (en) * | 2019-06-21 | 2019-09-20 | 卡瓦科尔牙科医疗器械（苏州）有限公司 | A kind of medical instrument sample circuit structure and the method for sampling for isolation detection |
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