A computer fan drive system capable of limiting starting current

Abstract

The present invention discloses a computer fan drive system capable of limiting starting current, including a fan M, and is characterized by further comprising: a photoelectric isolation module: used for conducting or cutting off the entire drive system according to the input voltage; an amplification drive module: connected to the photoelectric isolation module and the fan M respectively, and used for driving the fan M to work when the photoelectric isolation module conducts; a starting current limiting module: connected to the amplification drive module and the fan M respectively, and used for limiting the drive current of the fan M when the fan starts and the drive current increases. The present invention limits the current of the fan during startup through the starting current limiting module, preventing the working voltage of other components of the computer from being pulled down due to the increase in current when the fan starts.

Description

Technical Field

[0001] The present invention belongs to the field of computers, and specifically refers to a computer fan drive system capable of limiting starting current. Background Art

[0002] Computer fans are important components for computer heat dissipation. In existing computers, fans and other components inside the computer are all powered by a unified switching power supply. Since the current of the fan is relatively large when starting, and its peak value can reach more than twice that of normal operation, this may cause the switching power supply to be in a current limiting mode when the fan starts, resulting in the power supplied to other components of the computer in the power supply system being pulled down, affecting the normal operation of other components of the computer. Summary of the Invention

[0003] The purpose of the present invention is to overcome the above-mentioned defects existing when the computer fan starts, and provide a computer fan drive system capable of limiting starting current.

[0004] The purpose of the present invention is achieved by the following technical solutions: A computer fan drive system capable of limiting starting current, including a fan M, and further including:

[0005] An opto-isolation module: used to turn on or off the entire drive system according to the input voltage;

[0006] An amplification drive module: respectively connected to the opto-isolation module and the fan M, and used to drive the fan M to work when the opto-isolation module is turned on;

[0007] A starting current limiting module: respectively connected to the amplification drive module and the fan M, and used to limit the drive current of the fan M when the fan starts and the drive current increases.

[0008] Further, the starting current limiting module includes a triode VT2, a zener diode D1 with the N pole connected to the amplification drive module and the P pole connected to the emitter of the triode VT2, a capacitor C3 connected in parallel with the zener diode D1, a resistor R5 connected in series between the collector and emitter of the triode VT2, a capacitor C4 connected in series between the base and emitter of the triode VT2, a resistor R8 with one end connected to the base of the triode VT2 and the other end connected to the emitter of the triode VT2 through a resistor R11, a resistor R9 connected in series between the base and emitter of the triode VT2, and a resistor R10 with one end connected to the connection point of the resistor R8 and the resistor R11 and the other end connected to the emitter of the triode VT2; the emitter and collector of the triode VT2 are both connected to the amplification drive module, and its emitter is also grounded; the connection point of the resistor R8 and the resistor R11 is connected to the amplification drive module.

[0009] The amplification driving module includes an amplifier P, a triode VT1, a field effect transistor MOS, a resistor R4 with one end connected to the N pole of a zener diode D1 and the other end connected to the gate of the field effect transistor MOS, a potentiometer R3 connected in series between the collector of the triode VT1 and the gate of the field effect transistor MOS, a diode D2 with its P pole connected to the control end of the potentiometer R3 and its N pole connected to the negative pole of the amplifier P, a resistor R6 connected in series between the negative pole and the output end of the amplifier P, a resistor R7 connected in series between the base of the triode VT1 and the output end of the amplifier P, a diode D3 with its N pole connected to the emitter of the triode VT1 through a fan M and its P pole connected to the drain of the field effect transistor MOS; the gate of the field effect transistor MOS is respectively connected to the positive pole of the amplifier P and the collector of a triode VT2, and its source is connected to the connection point of a resistor R8 and a resistor R11; the collector of the triode VT1 is connected to the opto-isolation module.

[0010] The opto-isolation module includes an opto-coupler U, a resistor R1 connected in series between the first input terminal and the second input terminal of the opto-coupler U, and a capacitor C1 connected in parallel with the resistor R1; the first input terminal of the opto-coupler U is connected to a power supply, its second input terminal is grounded, its first output terminal is connected to the collector of the triode VT1, and its second output terminal is connected to the N pole of the zener diode D1.

[0011] The opto-isolation module further includes a capacitor C2 connected in series between the first output terminal and the second output terminal of the opto-coupler U, and a resistor R2 connected in parallel with the capacitor C2.

[0012] Compared with the prior art, the present invention has the following advantages and beneficial effects: By starting the current limiting module to limit the current of the fan during startup, the present invention prevents the current from rising during startup of the fan and pulling down the working voltage of other components of the computer. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is the circuit structure diagram of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] The present invention will be further described in detail below in conjunction with embodiments, but the embodiments of the present invention are not limited thereto.

[0015] Embodiment

[0016] As Figure 1 shown, the computer fan driving system capable of limiting the startup current of the present invention includes a fan M, an opto-isolation module, an amplification driving module, and a startup current limiting module.

[0017] Specifically, the opto-isolation module is used to turn on or off the entire driving system according to the input voltage.

[0018] The amplification driving module is respectively connected to the optoelectronic isolation module and the fan M, and is used to drive the fan M to work when the optoelectronic isolation module is turned on.

[0019] The starting current limiting module is respectively connected to the amplification driving module and the fan M, and is used to limit the driving current of the fan M when the fan starts and the driving current increases.

[0020] As Figure 1 shown, the starting current limiting module includes a triode VT2, a zener diode D1, a capacitor C3, a resistor R5, a resistor R9, a resistor R8, a capacitor C4, a resistor R10, and a resistor R11.

[0021] Among them, the N pole of the zener diode D1 is connected to the amplification driving module, and its P pole is connected to the emitter of the triode VT2. The capacitor C3 is connected in parallel with the zener diode D1. The resistor R5 is connected in series between the collector and emitter of the triode VT2. The capacitor C4 is connected in series between the base and emitter of the triode VT2. One end of the resistor R8 is connected to the base of the triode VT2, and the other end is connected to the emitter of the triode VT2 after passing through the resistor R11. The resistor R9 is connected in series between the base and emitter of the triode VT2. One end of the resistor R10 is connected to the connection point of the resistor R8 and the resistor R11, and the other end is connected to the emitter of the triode VT2. The emitter and collector of the triode VT2 are both connected to the amplification driving module, and its emitter is also grounded. The connection point of the resistor R8 and the resistor R11 is connected to the amplification driving module.

[0022] In addition, the amplification driving module includes an amplifier P, a triode VT1, a field effect transistor MOS, a resistor R4, a potentiometer R3, a diode D2, a resistor R6, a resistor R7, and a diode D3.

[0023] When connecting, one end of the resistor R4 is connected to the N pole of the zener diode D1, and the other end is connected to the gate of the field effect transistor MOS. The potentiometer R3 is connected in series between the collector of the triode VT1 and the gate of the field effect transistor MOS. The P pole of the diode D2 is connected to the control end of the potentiometer R3, and its N pole is connected to the negative pole of the amplifier P. The resistor R6 is connected in series between the negative pole and the output end of the amplifier P. The resistor R7 is connected in series between the base of the triode VT1 and the output end of the amplifier P. The N pole of the diode D3 is connected to the emitter of the triode VT1 after passing through the fan M, and its P pole is connected to the drain of the field effect transistor MOS. The gate of the field effect transistor MOS is respectively connected to the positive pole of the amplifier P and the collector of the triode VT2, and its source is connected to the connection point of the resistor R8 and the resistor R11. The collector of the triode VT1 is connected to the optoelectronic isolation module.

[0024] The optoelectronic isolation module includes an optocoupler U, a resistor R1 connected in series between the first input terminal and the second input terminal of the optocoupler U, and a capacitor C1 connected in parallel with the resistor R1. The first input terminal of the optocoupler U is connected to a 12V power supply, its second input terminal is grounded, the first output terminal is connected to the collector of a triode VT1, and the second output terminal is connected to the N pole of a zener diode D1. The first output terminal of the optocoupler U is also connected to a 12V power supply.

[0025] As another preference, the optoelectronic isolation module further includes a capacitor C2 connected in series between the first output terminal and the second output terminal of the optocoupler U, and a resistor R2 connected in parallel with the capacitor C2. When the optocoupler U is powered on and conducts, the voltages output from its first output terminal and second output terminal are filtered by the RC filtering link composed of the capacitor C2 and the resistor R2 and then supplied to the subsequent amplification driving module and the starting current limiting module.

[0026] During operation, a voltage is input to the input terminal of the optocoupler U. During this process, the voltage is filtered by the capacitor C1 to improve the stability of the voltage. When the voltage is input to the optocoupler U, the internal light-emitting diode is lit, causing the optocoupler U to conduct. The voltage is output from the output terminal of the optocoupler U and is filtered by the RC filtering link composed of the capacitor C2 and the resistor R2 and then supplied to the subsequent amplification driving module. One part of the voltage output by the optoelectronic isolation module is input to the amplification driving module, and the other part is input to the starting current limiting module; the voltage output by the starting current limiting module is applied to the source electrode of a field-effect transistor MOS, and the voltage input to the amplification driving module is applied to the gate electrode of the field-effect transistor MOS through a resistor R4, causing the field-effect transistor MOS to conduct; at the same time, one part of the voltage input to the amplification driving module is input to an amplifier P, amplified by the amplifier P, and then applied to the base electrode of the triode VT1 through a resistor R7, causing the triode VT1 to conduct. At this time, the fan M is powered on and starts. The resistor R6 is the negative feedback resistor of the amplifier P6, which can stabilize the static operating point of the amplifier P. In the starting current limiting module, the resistors R10 and R11 are sampling resistors. When the starting current of the fan increases during the starting process, the current sampling voltage on the resistors R10 and R11 increases, and it drives the triode VT2 after being divided by the resistors R8 and R9. As the current increases, the voltage on the resistors R10 and R11 increases. When the base voltage of the triode VT2 reaches a certain value, the triode VT2 starts to conduct. At this time, the triode VT2 is in the amplification region, and the voltage between its emitter and collector starts to decrease, thereby pulling down the driving voltage of the gate electrode of the field-effect transistor MOS, causing the field-effect transistor MOS to enter the saturation region. The voltage between the drain and source electrodes of the field-effect transistor MOS starts to increase, and the voltage drop between its drain and source electrodes bears a part of the output voltage, thereby causing the voltage across the fan to decrease, and further reducing the driving current of the fan, achieving the purpose of limiting the starting current of the fan.

[0027] In the above structure, the resistor R8 is the base current-limiting resistor of the triode VT2, and the resistors R8 and R9 form a voltage-dividing circuit. The capacitor C4 is a filtering capacitor, which is used to filter out the noise of the sampled current, and its filtering bandwidth The models and parameters of the electronic components in the drive system of this embodiment are as Figure 1 shown.

[0028] As described above, the present invention can be well implemented.

Claims

1. A computer fan drive system capable of limiting starting current, including a fan M, characterized in that, It also includes: An optoelectronic isolation module: used to turn on or off the entire drive system according to the input voltage; An amplification drive module: connected to the optoelectronic isolation module and the fan M respectively, and used to drive the fan M to work when the optoelectronic isolation module is turned on; A starting current limiting module: connected to the amplification drive module and the fan M respectively, and used to limit the drive current of the fan M when the fan starts and the drive current increases; The starting current limiting module includes a triode VT2, a voltage stabilizing diode D1 with its N pole connected to the amplification drive module and its P pole connected to the emitter of the triode VT2, a capacitor C3 connected in parallel with the voltage stabilizing diode D1, a resistor R5 connected in series between the collector and emitter of the triode VT2, a capacitor C4 connected in series between the base and emitter of the triode VT2, a resistor R8 with one end connected to the base of the triode VT2 and the other end connected to the emitter of the triode VT2 after passing through a resistor R11, a resistor R9 connected in series between the base and emitter of the triode VT2, and a resistor R10 with one end connected to the connection point of the resistor R8 and the resistor R11 and the other end connected to the emitter of the triode VT2; the emitter and collector of the triode VT2 are both connected to the amplification drive module, and its emitter is also grounded; the connection point of the resistor R8 and the resistor R11 is connected to the amplification drive module; The amplification drive module includes an amplifier P, a triode VT1, a field effect transistor MOS, a resistor R4 with one end connected to the N pole of the voltage stabilizing diode D1 and the other end connected to the gate of the field effect transistor MOS, a potentiometer R3 connected in series between the collector of the triode VT1 and the gate of the field effect transistor MOS, a diode D2 with its P pole connected to the control end of the potentiometer R3 and its N pole connected to the negative pole of the amplifier P, a resistor R6 connected in series between the negative pole and the output end of the amplifier P, a resistor R7 connected in series between the base of the triode VT1 and the output end of the amplifier P, a diode D3 with its N pole connected to the emitter of the triode VT1 after passing through the fan M and its P pole connected to the drain of the field effect transistor MOS; the gate of the field effect transistor MOS is connected to the positive pole of the amplifier P and the collector of the triode VT2 respectively, and its source is connected to the connection point of the resistor R8 and the resistor R11; the collector of the triode VT1 is connected to the optoelectronic isolation module.

2. The computer fan drive system capable of limiting starting current according to claim 1, characterized in that, The optoelectronic isolation module includes an optocoupler U, a resistor R1 connected in series between the first input terminal and the second input terminal of the optocoupler U, and a capacitor C1 connected in parallel with the resistor R1; the first input terminal of the optocoupler U is connected to the power supply, its second input terminal is grounded, its first output terminal is connected to the collector of the triode VT1, and its second output terminal is connected to the N pole of the voltage stabilizing diode D1.

3. The computer fan drive system capable of limiting starting current according to claim 2, characterized in that, The optoelectronic isolation module also includes a capacitor C2 connected in series between the first output terminal and the second output terminal of the optocoupler U, and a resistor R2 connected in parallel with the capacitor C2.

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