Direct current motor speed regulation drive circuit

Abstract

The utility model discloses a direct current motor speed regulation driving circuit, which belongs to the technical field of direct current motor driving, and is characterized in that a square wave pulse signal output end MOTO of an MCU (Microprogrammed Control Unit) is electrically connected with an input end of a secondary MOS (Metal Oxide Semiconductor) amplification module, an output end of the secondary MOS amplification module is electrically connected with a G pole of a high-power N-channel MOS tube Q3, an S pole of the high-power N-channel MOS tube Q3 is grounded, and an output end of the high-power N-channel MOS tube Q3 is electrically connected with an output end of a secondary MOS amplification module. The D pole of the high-power N-channel MOS tube Q3 is electrically connected with a direct-current motor port MOTON, the direct-current motor port MOTON is electrically connected with a direct-current motor port MOTOP through a capacitor C5, the direct-current motor port MOTON is further electrically connected with the first end of a capacitor C6, the second end of the capacitor C6 is grounded, and the direct-current motor port MOTOP is electrically connected with a power module. The direct current motor speed regulation driving circuit solves the problem that the existing motor driving circuit adopts two MOS tubes, so that power equalization is difficult to realize.

Description

Technical Field

[0001] The utility model relates to the technical field of direct current motor drive, in particular to a direct current motor speed regulation drive circuit. Background Art

[0002] Existing DC motor drive circuit, such as Figure 1 As shown, the input analog voltage signal is mainly converted into an output pulse signal with different duty cycles through the comparator chip U1, and the signal is amplified and the output capacity is enhanced through the push-pull circuit (composed of transistors Q3 and Q4). At the same time, the amplified pulse signal controls the connection and cutoff of two MOS tubes Q1 and Q2 of the same F3205S, thereby converting the input analog voltage into a pulse signal for controlling the motor speed and driving the motor to work at different speeds. Because the analog signal is converted into a pulse signal through the comparator chip U1, and two MOS tubes Q1 and Q2 are used to drive the motor to rotate, while the driving capacity is improved, the power consumption and heat generation of MOS tubes Q1 and Q2 are also increased. It is difficult for the two MOS tubes Q1 and Q2 to achieve equal power sharing, and there will be a phenomenon that one MOS tube is overloaded and the other MOS tube is underloaded, and there is a risk of heat damage to components. Utility Model Content

[0003] In order to overcome the defects of the prior art, the utility model provides a DC motor speed regulation drive circuit to solve the above problems.

[0004] The technical solution adopted by the utility model to solve the technical problem is: a DC motor speed regulation drive circuit, including MCU, a secondary MOS amplifier module, a high-power N-channel MOS tube Q3, a capacitor C5, a capacitor C6, a DC motor port MOTO_P and a DC motor port MOTO_N;

[0005] The square wave pulse signal output terminal MOTO of the MCU is electrically connected to the input terminal of the secondary MOS amplifier module, the output terminal of the secondary MOS amplifier module is electrically connected to the G pole of the high-power N-channel MOS tube Q3, the S pole of the high-power N-channel MOS tube Q3 is grounded, the D pole of the high-power N-channel MOS tube Q3 is electrically connected to the DC motor port MOTO_N, the DC motor port MOTO_N is electrically connected to the DC motor port MOTO_P through the capacitor C5, the DC motor port MOTO_N is also electrically connected to the first end of the capacitor C6, the second end of the capacitor C6 is grounded, and the DC motor port MOTO_P is electrically connected to the power module.

[0006] It is worth noting that the secondary MOS amplification module includes N-channel MOS transistors Q1 and Q2, resistors R4 and R5;

[0007] The G pole of the N-channel MOS tube Q1 is electrically connected to the square wave pulse signal output terminal MOTO of the MCU, the S pole of the N-channel MOS tube Q1 is grounded, the D pole of the N-channel MOS tube Q1 is electrically connected to the first end of the resistor R4, the second end of the resistor R4 is electrically connected to the G pole of the N-channel MOS tube Q2 and the first end of the resistor R5 respectively, the S pole of the N-channel MOS tube Q2 is electrically connected to the G pole of the high-power N-channel MOS tube Q3, and the D pole of the N-channel MOS tube Q2 is electrically connected to the second end of the resistor R5 and the power module respectively.

[0008] Optionally, it further includes an analog signal input processing module, wherein the analog signal input processing module includes a fuse F2, a bidirectional diode D7, an inductor L4, a capacitor C12, a common mode inductor L6, a resistor R25 and a resistor R26;

[0009] The positive electrode of the external analog signal generating module is electrically connected to the first end of the fuse F2, the second end of the fuse F2 is electrically connected to the first end of the inductor L4, the second end of the inductor L4 is electrically connected to the first end of the bidirectional diode D7, the first end of the capacitor C12 and the first end of the first winding of the common mode inductor L6, the second end of the first winding of the common mode inductor L6 is electrically connected to the first end of the resistor R25, the other end of the resistor R25 is electrically connected to the first end of the resistor R26 and the analog input terminal ADJIN of the MCU, and the second end of the resistor R26 is grounded;

[0010] The cathode of the external analog signal generating module, the second end of the bidirectional diode D7 and the second end of the capacitor C12 are all electrically connected to the first end of the second winding of the common mode inductor L6, and the second end of the second winding of the common mode inductor L6 is grounded.

[0011] Preferably, it also includes a collection module, which includes a resistor R11, a resistor R12 and a resistor R13, the first end of the resistor R11 is electrically connected to the S pole of the high-power N-channel MOS tube Q3, the second end of the capacitor C6 and the first end of the resistor R12, respectively, the second end of the resistor R11 is grounded, the second end of the resistor R12 is electrically connected to the first end of the resistor R13, and the second end of the resistor R13 is electrically connected to the current sampling input terminal Cin of the MCU.

[0012] Specifically, the resistor R11 is a manganese copper wire.

[0013] It is worth noting that it also includes an LED lamp group, which includes multiple LED lamps with input ends connected in parallel, the input end of the LED lamp group is electrically connected to a power supply module, and the output end of each LED lamp in the LED lamp group has a corresponding port on the MCU and is electrically connected to the corresponding port, so that when the corresponding port of the MCU outputs a low level, the corresponding LED lamp will emit light.

[0014] The beneficial effect of the utility model is that in the DC motor speed control driving circuit, an analog quantity of 0 to 5V is input externally to the MCU, and the analog quantity input by the MCU drives the secondary MOS amplifier module to amplify the square wave pulse signal of 0 to 5V output by the MCU into a square wave pulse signal of 0 to 24V, thereby driving the high-power N-channel MOS tube Q3, and driving the DC motor through the high-power N-channel MOS tube Q3, and the square wave pulse signal with different duty ratios can be output by the MCU to drive the on-off time of the high-power N-channel MOS tube Q3, thereby adjusting the speed of the motor. In this way, since only one MOS tube is used to drive the DC motor, compared with the prior art that two MOS are used to drive the DC motor to rotate, there will be no problem of uneven power distribution, avoiding heating and damage of components, thereby improving the overall stability of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A circuit diagram of an existing DC motor drive circuit;

[0016] Figure 2 A circuit diagram of a DC motor speed regulation drive circuit in one embodiment of the utility model;

[0017] Figure 3 A circuit diagram of an analog signal input processing module in one embodiment of the utility model;

[0018] Figure 4 This is a circuit diagram of an LED lamp group in one embodiment of the utility model. DETAILED DESCRIPTION

[0019] The specific implementation methods of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these implementation methods is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each implementation method of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0020] like Figure 2-4As shown, a DC motor speed regulation drive circuit includes an MCU, a secondary MOS amplifier module, a high-power N-channel MOS tube Q3, a capacitor C5, a capacitor C6, a DC motor port MOTO_P and a DC motor port MOTO_N; in this embodiment, the model of the high-power N-channel MOS tube Q3 is YJB200G06B;

[0021] The square wave pulse signal output terminal MOTO of the MCU is electrically connected to the input terminal of the secondary MOS amplifier module, the output terminal of the secondary MOS amplifier module is electrically connected to the G pole of the high-power N-channel MOS tube Q3, the S pole of the high-power N-channel MOS tube Q3 is grounded, the D pole of the high-power N-channel MOS tube Q3 is electrically connected to the DC motor port MOTO_N, the DC motor port MOTO_N is electrically connected to the DC motor port MOTO_P through the capacitor C5, the DC motor port MOTO_N is also electrically connected to the first end of the capacitor C6, the second end of the capacitor C6 is grounded, and the DC motor port MOTO_P is electrically connected to the power module. A diode D4 is provided between the DC motor port MOTO_N and the DC motor port MOTO_P, wherein the positive pole of the diode D4 is electrically connected to the DC motor port MOTO_P, and the negative pole of the diode D4 is electrically connected to the DC motor port MOTO_N, so as to avoid current backflow.

[0022] In the DC motor speed control driving circuit, an analog quantity of 0 to 5V is input externally to the MCU, and the analog quantity input by the MCU drives the secondary MOS amplifier module to amplify the square wave pulse signal of 0 to 5V output by the MCU into a square wave pulse signal of 0 to 24V, thereby driving the high-power N-channel MOS tube Q3, and driving the DC motor through the high-power N-channel MOS tube Q3, and the square wave pulse signal with different duty ratios can be output by the MCU to drive the on-off time of the high-power N-channel MOS tube Q3, thereby adjusting the speed of the motor. In this way, since only one MOS tube is used to drive the DC motor, compared with the prior art that uses two MOS to drive the DC motor to rotate, there will be no problem of uneven power distribution, avoiding heating and damage of components, thereby improving the overall stability of the circuit.

[0023] It is worth noting that the secondary MOS amplification module includes N-channel MOS transistors Q1 and Q2, resistors R4 and R5; the G pole of the N-channel MOS transistor Q1 is electrically connected to the square wave pulse signal output terminal MOTO of the MCU, the S pole of the N-channel MOS transistor Q1 is grounded, the D pole of the N-channel MOS transistor Q1 is electrically connected to the first end of the resistor R4, the second end of the resistor R4 is electrically connected to the G pole of the N-channel MOS transistor Q2 and the first end of the resistor R5, the S pole of the N-channel MOS transistor Q2 is electrically connected to the G pole of the high-power N-channel MOS transistor Q3, and the D pole of the N-channel MOS transistor Q2 is electrically connected to the second end of the resistor R5 and the power module. When the square wave pulse signal output terminal MOTO of the MCU outputs a high level, the N-channel MOS transistor Q1 is turned on, thereby enabling the N-channel MOS transistor Q2 to be turned on, and then enabling the high-power N-channel MOS transistor Q3 to be turned on.

[0024] Optional, such as Figure 3 As shown, it also includes an analog signal input processing module, which includes a fuse F2, a bidirectional diode D7, an inductor L4, a capacitor C12, a common-mode inductor L6, a resistor R25 and a resistor R26; the positive electrode of the external analog signal generating module is electrically connected to the first end of the fuse F2, the second end of the fuse F2 is electrically connected to the first end of the inductor L4, and the second end of the inductor L4 is respectively connected to the first end of the bidirectional diode D7, the first end of the capacitor C12 and the first winding of the common-mode inductor L6 The first end of the common mode inductor L6 is electrically connected, the second end of the first winding of the common mode inductor L6 is electrically connected to the first end of the resistor R25, the other end of the resistor R25 is electrically connected to the first end of the resistor R26 and the analog input terminal ADJIN of the MCU respectively, and the second end of the resistor R26 is grounded; the negative electrode of the external analog signal generating module, the second end of the bidirectional diode D7 and the second end of the capacitor C12 are all electrically connected to the first end of the second winding of the common mode inductor L6, and the second end of the second winding of the common mode inductor L6 is grounded. The bidirectional diode D7 is used for clamping, the inductor L4 and the capacitor C12 form an LC filter circuit, and combined with the common mode inductor L6 to filter and reduce the distortion of the input analog signal, in addition, the capacitor C12 can also be used as a filter capacitor and overshoot compensation to further reduce the distortion of the input signal; the resistor R25 and the resistor R26 are set to serve the purpose of voltage division, and the voltage input to the analog input terminal ADJIN of the MCU is the voltage applied to both ends of the resistor R26. In this embodiment, the analog input port of the external analog signal generating module is Figure 3The MCU adjusts the duty cycle of the square wave pulse signal according to the size of the input analog quantity to adjust the speed of the DC motor, thereby ensuring the torque of the DC motor when it is working and also relatively maintaining the speed stability of the DC motor.

[0025] Specifically, it also includes a collection module, which includes a resistor R11, a resistor R12 and a resistor R13. The first end of the resistor R11 is electrically connected to the S pole of the high-power N-channel MOS tube Q3, the second end of the capacitor C6 and the first end of the resistor R12 respectively. The second end of the resistor R11 is grounded, the second end of the resistor R12 is electrically connected to the first end of the resistor R13, and the second end of the resistor R13 is electrically connected to the current sampling input terminal Cin of the MCU.

[0026] Preferably, the resistor R11 is a manganese copper wire. When the DC motor is working, the current driving the DC motor to work will first pass through the resistor R11 made of manganese copper wire to the ground, a sampling point is set at the first end of the resistor R11, and a small signal sampling module is formed by resistor R12, resistor R13, capacitor C7 and capacitor C8, wherein capacitor C7 and capacitor C8 are used for filtering, and after the protection of the resistor R11, the DC motor short circuit in a very short time will not damage the MCU, and the short circuit state can also be judged by the sampling module, and the short circuit time and short circuit times can be calculated. In addition, the self-recovery fuse F2 is also set up for possible long-term short circuits. And such a design can avoid the use of inferior DC motors that cause damage to the driver board.

[0027] It is worth noting that if Figure 4 As shown, it also includes an LED lamp group, the LED lamp group includes a plurality of LED lamps with input ends connected in parallel, the input end of the LED lamp group is electrically connected to the power module, and the output end of each LED lamp in the LED lamp group has a corresponding port on the MCU and is electrically connected to the corresponding port, so that when the corresponding port of the MCU outputs a low level, the corresponding LED lamp emits light. In this embodiment, the MCU controls the on and off of LED1 to LED5, thereby realizing a low-cost and cost-effective visual speed display, wherein when the input signal is 0-1V, LED1 is always on, when the input signal reaches the interval of 1-2V, LED1 and LED2 are always on, and increase accordingly, when the input signal is in the interval of 4-5V, the 5 LED lamps will be always on; the short circuit time and the number of short circuits are calculated in the MCU through a program, and if a short circuit or overload is detected multiple times in a short time, LED1-LED5 will flicker, and the power supply needs to be restarted to restart the driver board, and if the short circuit state is not detected multiple times in a short time, the normal working state is restored.

[0028] Specifically: when the DC motor is short-circuited, the current flowing through the DC motor suddenly increases, triggering the self-resetting fuse F1 to disconnect, and this solution sets a protection current on the program side that is less than the tripping current of the self-resetting fuse F1, and this protection current is larger than the normal working current of the DC motor. When the motor is short-circuited for a short time, this solution collects the DC motor current at this time greater than the protection current through the sampling module, and times and counts in the MCU. When 3 or more times are collected within 5 seconds, the 5 LED lights showing the speed will flash once per second.

[0029] This solution uses the reference voltage chip TL431 to provide a reference voltage for the MCU, and based on this, a sampling module is formed by resistors R11, R12, R13, capacitors C7 and C8 to determine the working status of the DC motor. This solution uses a dedicated reference voltage chip to provide a reference voltage, and uses direct sampling of the sampling module rather than isolated sampling, which ensures the sampling accuracy and the immediacy of the sampling judgment. At the same time, the manganese copper wire resistor R11 is used as a high-precision sampling resistor, which can achieve a higher current resistance value, thereby achieving short-circuit judgment without causing hardware damage.

[0030] In this embodiment, the power supply module includes a linear regulator U1, whose model is 75L05, and the input end of the linear regulator U1 is connected to the external power supply VCC; wherein, the input end of the LED lamp group and the power end of the terminal H2 corresponding to the analog input port are electrically connected to the output end of the linear regulator U1, thereby using the voltage stabilized by the linear regulator U1, and the DC motor port MOTO_P is electrically connected to the input end of the linear regulator U1, thereby directly using the voltage of the external power supply VCC.

[0031] In this embodiment, the analog ground and the digital ground are separated, and the plane of the analog ground and the plane of the digital ground are connected by magnetic beads in a single-point grounding manner to separate the analog ground from the digital ground, effectively reducing the interference of the analog devices caused by the operation of the digital devices. Specifically, the second end of the resistor R11 is electrically connected to the digital ground, the second end of the resistor R12 is electrically connected to the analog ground through the capacitor C7, the second end of the resistor R26 is electrically connected to the analog ground, the second end of the second winding of the common mode inductor L6 is electrically connected to the analog ground, and the ground terminal GND of the MCU is electrically connected to the analog ground.

[0032] At the same time, this solution uses a software program to determine the duty cycle of the output DC motor drive pulse, realizes a simple speed judgment of the DC motor, and outputs a signal of whether the motor is running normally through the MCU port FB (i.e. pin 9). The signal output port is Figure 2 Terminal H1 in the

[0033] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the scope of protection of the present invention.

Claims

1. A DC motor speed regulation drive circuit, characterized in that: It includes MCU, secondary MOS amplifier module, high-power N-channel MOS tube Q3, capacitor C5, capacitor C6, DC motor port MOTO_P and DC motor port MOTO_N; The square wave pulse signal output terminal MOTO of the MCU is electrically connected to the input terminal of the secondary MOS amplifier module, the output terminal of the secondary MOS amplifier module is electrically connected to the G pole of the high-power N-channel MOS tube Q3, the S pole of the high-power N-channel MOS tube Q3 is grounded, the D pole of the high-power N-channel MOS tube Q3 is electrically connected to the DC motor port MOTO_N, the DC motor port MOTO_N is electrically connected to the DC motor port MOTO_P through the capacitor C5, the DC motor port MOTO_N is also electrically connected to the first end of the capacitor C6, the second end of the capacitor C6 is grounded, and the DC motor port MOTO_P is electrically connected to the power module.

2. A DC motor speed regulation drive circuit according to claim 1, characterized in that: The secondary MOS amplification module includes N-channel MOS transistors Q1 and Q2, resistors R4 and R5; The G pole of the N-channel MOS tube Q1 is electrically connected to the square wave pulse signal output terminal MOTO of the MCU, the S pole of the N-channel MOS tube Q1 is grounded, the D pole of the N-channel MOS tube Q1 is electrically connected to the first end of the resistor R4, the second end of the resistor R4 is electrically connected to the G pole of the N-channel MOS tube Q2 and the first end of the resistor R5 respectively, the S pole of the N-channel MOS tube Q2 is electrically connected to the G pole of the high-power N-channel MOS tube Q3, and the D pole of the N-channel MOS tube Q2 is electrically connected to the second end of the resistor R5 and the power module respectively.

3. A DC motor speed regulation drive circuit according to claim 1, characterized in that: Also includes an analog signal input processing module, the analog signal input processing module includes a fuse F2, a bidirectional diode D7, an inductor L4, a capacitor C12, a common mode inductor L6, a resistor R25 and a resistor R26; The positive electrode of the external analog signal generating module is electrically connected to the first end of the fuse F2, the second end of the fuse F2 is electrically connected to the first end of the inductor L4, the second end of the inductor L4 is electrically connected to the first end of the bidirectional diode D7, the first end of the capacitor C12 and the first end of the first winding of the common mode inductor L6, the second end of the first winding of the common mode inductor L6 is electrically connected to the first end of the resistor R25, the other end of the resistor R25 is electrically connected to the first end of the resistor R26 and the analog input terminal ADJIN of the MCU, and the second end of the resistor R26 is grounded; The cathode of the external analog signal generating module, the second end of the bidirectional diode D7 and the second end of the capacitor C12 are all electrically connected to the first end of the second winding of the common mode inductor L6, and the second end of the second winding of the common mode inductor L6 is grounded.

4. A DC motor speed regulation drive circuit according to claim 1, characterized in that: It also includes a collection module, which includes a resistor R11, a resistor R12 and a resistor R13. The first end of the resistor R11 is electrically connected to the S pole of the high-power N-channel MOS tube Q3, the second end of the capacitor C6 and the first end of the resistor R12 respectively. The second end of the resistor R11 is grounded, the second end of the resistor R12 is electrically connected to the first end of the resistor R13, and the second end of the resistor R13 is electrically connected to the current sampling input terminal Cin of the MCU.

5. A DC motor speed regulation drive circuit according to claim 4, characterized in that: The resistor R11 is a manganese copper wire.

6. A DC motor speed regulation drive circuit according to claim 1, characterized in that: It also includes an LED lamp group, which includes a plurality of LED lamps with input ends connected in parallel, the input end of the LED lamp group is electrically connected to a power module, and the output end of each LED lamp in the LED lamp group has a corresponding port on the MCU and is electrically connected to the corresponding port, so that when the corresponding port of the MCU outputs a low level, the corresponding LED lamp emits light.

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