TW201303576A - Alarm circuit of fan fault - Google Patents

Abstract

An alarm circuit of fan fault includes a fan controller, a first rectifying circuit, a switch circuit, a first indication circuit, a second rectifying circuit, a comparing circuit and a second indication circuit. The rotational-speed-control pin of the fan controller is connected to the first indication circuit via the first rectifying circuit and the switch circuit successively, and the rotational-speed-detection pin of the fan is coupled to the second indication circuit via the second rectifying circuit and the comparing circuit successively. When the fan works wrong, the alarm circuit of fan fault informs a user by the first and the second indication circuit such that the user can find and settle the fault.

Description

Fan failure alarm circuit

The invention relates to a fan fault alarm circuit.

The computer and the server often set the fan in the chassis to dissipate heat from various components in the chassis, such as the central processing unit. When the fan fails, such as fan speed detection or control failure, but cannot be found in time, the heat dissipation in the chassis is not timely. As a result, the internal temperature is much higher than the operating temperature of the component, which makes the components in the chassis unstable or even malfunctions.

In view of the above, it is necessary to provide a fan failure alarm circuit that can notify the user in time when the fan fails.

A fan fault alarm circuit includes:

a fan controller includes a speed control pin and a speed detecting pin, wherein the speed control pin is used for outputting a control signal, and the speed detecting pin is configured to output a detecting signal;

a first rectifier circuit is configured to convert the control signal into a first DC signal;

a switching circuit is configured to output a corresponding switching signal according to the first DC signal;

a first indicating circuit is configured to indicate, according to the switching signal, whether a fan controlled by the fan controller has an operational fault;

a second rectifier circuit is configured to convert the detection signal into a second DC signal;

a comparison circuit is configured to compare the second DC signal with a first reference voltage and a second reference voltage, respectively, and output a comparison signal;

A second indicating circuit is configured to indicate, according to the comparison signal, whether the fan has an operational fault.

The fan fault alarm circuit notifies the user when the fan has an operational fault through the first indicating circuit and the second indicating circuit, so that the user can discover and eliminate the fault in time.

Referring to FIG. 1 , a preferred embodiment of the fan fault alarm circuit 100 includes a fan controller 10 for controlling a fan speed, a first rectifier circuit 20 , a switch circuit 60 , and a first indicating circuit 70 . A second rectifier circuit 30, a comparison circuit 40 and a second indicator circuit 50. The speed control pin 16 of the fan controller 10 is sequentially connected to the first indicating circuit 70 through the first rectifier circuit 20 and the switch circuit 60. The rotation speed detecting pin 14 of the fan controller 10 sequentially transmits the second rectifying circuit. The circuit 30 and the comparison circuit 40 are connected to the second indication circuit 50.

The fan controller 10 is configured to output a control signal to the first rectifier circuit 20 through the speed control pin 16, and output a detection signal to the second rectifier circuit 30 through the speed detection pin 14. According to the working principle of the fan controller 10, when the fan operation fails, the control signal outputted by the rotation speed control pin 16 of the fan controller 10 is a low level signal, and the detection signal output by the rotation detecting pin 14 is detected. It is a high level signal V1 or a low level signal V2; when the fan is working normally, the control signal outputted by the speed control pin 16 is a pulse signal or a high level signal, and the detection of the rotation speed detecting pin 14 is detected. The signal is a pulse signal.

The first rectifier circuit 20 is configured to convert the control signal into a first DC signal.

The switch circuit 60 is configured to output a corresponding switch signal according to the first DC signal.

The first indicating circuit 70 is configured to indicate, according to the switching signal, whether the fan has an operational fault.

The second rectifying circuit 30 is configured to convert the detection signal into a second DC signal V3, wherein the voltage value of the second DC signal V3 is greater than the voltage value of the low level signal V2 and less than the high level signal V1 Voltage value.

The comparison circuit 40 is configured to compare the second DC signal V3 with a first reference voltage Vref1 and a second reference voltage Vref2, respectively, and output a comparison signal.

The second indicating circuit 50 is configured to indicate, according to the comparison signal, whether the fan has an operational failure.

The first rectifying circuit 20 includes a resistor R1, a transistor D1 and a capacitor C1. One end of the resistor R1 is connected to the rotation speed control pin 16 of the fan controller 10, and the other end is connected to the anode of the transistor D1. The cathode is grounded through the capacitor C1.

The switching circuit 60 includes a triode Q1 and Q2 and a resistor R2 and R3. The base of the triode Q1 is connected to the cathode of the transistor D1. The collector of the triode Q1 passes through the resistor R2 and the DC power supply VCC. Connected, the emitter of the triode Q1 is grounded, the base of the triode Q2 is connected to the collector of the triode Q1, and the collector of the triode Q2 is connected to the DC power source VCC through the resistor R3. The emitter of the polar body Q2 is grounded.

The first indicating module 70 includes a resistor R4, a transistor D2, a capacitor C2, and a buzzer F1. The cathode of the transistor D2 is connected to the DC power source VCC. The anode of the transistor D2 is grounded through the capacitor C2, and is connected to the cathode. The collector of the triode Q2, the first end of the buzzer F1 is connected to the DC power source VCC, and the second end is connected to the anode of the transistor D2 through the resistor R4.

The second rectifier circuit 30 includes a resistor R5 and a capacitor C3. The first end of the resistor R5 is connected to the rotation detecting pin 14 of the fan controller 10, and the second end is grounded through the capacitor C3.

The comparison circuit 40 includes operational amplifiers U1 and U2 and resistors R6-R9. The non-inverting input terminal of the operational amplifier U1 is connected to the DC power supply VCC through a resistor R6, and is also grounded through a resistor R7. The inverting input terminal of the operational amplifier U1 is The non-inverting input terminals of the operational amplifier U2 are connected to the second end of the resistor R5, and the output terminals of the operational amplifiers U1 and U2 are connected to the second indicating circuit 50.

The second indicating circuit 50 includes a resistor R10, a transistor D3, a capacitor C4, and a buzzer F2. The cathode of the transistor D3 is connected to the DC power source VCC. The anode of the transistor D3 is grounded through the capacitor C4, and the operation is also connected. The output ends of the amplifiers U1 and U2, the first end of the buzzer F2 is connected to the DC power source VCC, and the second end is connected to the anode of the transistor D3 through the resistor R10.

The working principle of the preferred embodiment of the present invention will be described below:

For the first indicating circuit 70, when the fan is working normally, it is assumed that the control signal outputted by the rotation speed control pin 16 is a pulse signal, and at this time, the pulse signal is converted into the first through the first rectifying and filtering circuit 20. The DC signal is input to the base of the triode Q1, so that the triode Q1 is turned on, and then the base of the triode Q2 is grounded, and the triode Q2 is turned off, so that the buzzer F1 The second end is pulled up to the DC power source VCC, and at this time, the buzzer F1 does not sound.

When the fan is working normally, if the control signal outputted by the speed control pin 16 is a high level signal, the high level signal is input to the base of the triode Q1 through the first rectifying and filtering circuit 20, Similarly, the buzzer F1 does not sound.

When the fan is faulty, the control signal outputted by the speed control pin 16 is a low level signal, and the low level signal is input to the base of the triode Q1 through the first finishing circuit 20, so that the three The pole body Q1 is turned off, and then the base of the triode Q2 is pulled up to the DC power source VCC, then the triode Q2 is turned on, so that the second end of the buzzer F1 is pulled down to the ground, at this time, The buzzer F1 sounds to inform the user that the fan has failed.

For the second indication circuit 50, when the fan is working normally, the detection signal outputted by the rotation detecting pin 14 is a pulse signal, and the pulse signal is converted into the second DC signal V3 through the second rectifying circuit 30. Input to the inverting input terminal of the operational amplifier U1 and the non-inverting input terminal of the operational amplifier U2. At this time, the voltage of the non-inverting input terminal of the operational amplifier U1 is the voltage across the resistor R7, that is, the first reference voltage Vref1, The voltage value of the first reference voltage Vref1 is set to be equal to the voltage value of the high-level signal V1, and the second DC signal V3 is obtained by the voltage value of the resistors R6 and R7. The voltage value of the second DC signal V3 is smaller than the first reference voltage Vref1, that is, the voltage of the inverting input terminal of the operational amplifier U1 is smaller than the voltage of the non-inverting input terminal, so that the voltage value is lower than the voltage value of the high-level signal V1. The output of the operational amplifier U1 is at a high level. At the same time, the voltage at the inverting input terminal of the operational amplifier U2 is the voltage across the resistor R9, that is, the second reference voltage Vref2, and the voltage value thereof is obtained by adjusting the resistance values of the resistors R8 and R9. In this embodiment, the first The voltage of the second reference voltage Vref2 is set to be equal to the voltage value of the low level signal V2, and the voltage value of the second direct current signal V3 is greater than the voltage value of the low level signal V2, the voltage value of the second direct current signal V3 is greater than The second reference voltage Vref2, that is, the voltage of the non-inverting input terminal of the operational amplifier U2 is greater than the voltage of the inverting input terminal, so that the output end of the operational amplifier U2 is at a high level, and therefore, the second end of the buzzer F2 receives The voltage is high, and at this time, the buzzer F2 does not sound.

When the fan is faulty, it is assumed that the detection signal output by the rotation detecting pin 14 is the high level signal V1. At this time, the high level signal V1 is input to the operational amplifier U1 through the second rectifying circuit 30. An inverting input terminal and a non-inverting input terminal of the operational amplifier U2. At this time, the voltage value of the high level signal V2 is greater than the first and second reference voltages Vref1 and Vref2, that is, the voltage of the inverting input terminal of the operational amplifier U1. When the voltage of the non-inverting input terminal is greater than the voltage of the non-inverting input terminal, the voltage of the non-inverting input terminal of the operational amplifier U2 is greater than the voltage of the inverting input terminal, and the output voltage of the output terminal of the operational amplifier U1 is a low level, and the output voltage of the output terminal of the operational amplifier U2 is The high level causes the voltage received by the second end of the buzzer F2 to be low, which in turn causes the buzzer F2 to sound to notify the user that the fan has an operational failure.

When the fan is faulty, it is assumed that the detection signal output by the rotation detecting pin 14 is the low level signal V2. At this time, the low level signal V2 is input to the operational amplifier U1 through the second rectifying circuit 30. An inverting input terminal and a non-inverting input terminal of the operational amplifier U2. At this time, the voltage value of the low level signal V2 is smaller than the first and second reference voltages Vref1 and Vref2, that is, the voltage of the non-inverting input terminal of the operational amplifier U1 is greater than The voltage at the inverting input terminal, the voltage at the inverting input terminal of the operational amplifier U2 is greater than the voltage at the non-inverting input terminal, the output terminal of the operational amplifier U1 is at a high level, and the output terminal of the operational amplifier U2 is at a low level, so that the bee The voltage received by the second end of the horn F2 is at a low level, which in turn causes the buzzer F2 to beep to inform the user that the fan is malfunctioning.

As can be seen from the above, in the present embodiment, the triodes Q1 and Q2 both function as electronic switches. Therefore, in other embodiments, the triodes Q1 and Q2 may be replaced by other types of transistors, and even others have electrons. The electronic components or chips of the switching function can be used.

The fan failure alarm circuit 100 notifies the user through the first indication circuit 70 and the second indication circuit 50 when the fan has an operational failure, so that the user can find and eliminate the fault in time.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims.

100. . . Fan failure alarm circuit

20. . . First rectifier circuit

60. . . Switch circuit

70. . . First indicating circuit

30. . . Second rectifier circuit

40. . . Comparison circuit

50. . . Second indicating circuit

R1-R10. . . resistance

D1-D3. . . Transistor

F1, F2. . . buzzer

Q1, Q2. . . Field effect transistor

U1, U2. . . Operational Amplifier

C1-C4. . . capacitance

10. . . Fan controller

1 is a circuit diagram of a preferred embodiment of a fan fault alarm circuit of the present invention.

100. . . Fan failure alarm circuit

20. . . First rectifier circuit

60. . . Switch circuit

70. . . First indicating circuit

30. . . Second rectifier circuit

40. . . Comparison circuit

50. . . Second indicating circuit

R1-R10. . . resistance

D1-D3. . . Transistor

F1, F2. . . buzzer

Q1, Q2. . . Field effect transistor

U1, U2. . . Operational Amplifier

C1-C4. . . capacitance

10. . . Fan controller

Claims (9)

A fan fault alarm circuit includes:
a fan controller includes a speed control pin and a speed detecting pin, wherein the speed control pin is used for outputting a control signal, and the speed detecting pin is configured to output a detecting signal;
a first rectifier circuit is configured to convert the control signal into a first DC signal;
a switching circuit is configured to output a corresponding switching signal according to the first DC signal;
a first indicating circuit is configured to indicate, according to the switching signal, whether a fan controlled by the fan controller has an operational fault;
a second rectifier circuit is configured to convert the detection signal into a second DC signal;
a comparison circuit is configured to compare the second DC signal with a first reference voltage and a second reference voltage, and output a comparison signal; and a second indication circuit is configured to indicate, according to the comparison signal, whether the fan has a working fault . The fan fault alarm circuit of claim 1, wherein the first rectifier circuit comprises a first resistor, a first transistor and a first capacitor, and one end of the first resistor is connected to the speed control of the fan controller. The other end is connected to the anode of the first transistor, and the cathode of the first transistor is grounded through the first capacitor. The fan fault alarm circuit of claim 2, wherein the switch circuit comprises a first electronic switch, a second electronic switch, a second resistor and a third resistor, the first end of the first electronic switch being connected to the electric a cathode of the crystal, the second end of the first electronic switch is connected to the DC power source through the second resistor, the third end of the first electronic switch is grounded, and the first end of the second electronic switch is connected to the first electronic switch The second end of the second electronic switch is connected to the DC power source through the third resistor, and the third end of the second electronic switch is grounded. The fan fault alarm circuit of claim 3, wherein the first electronic switch is a triode, and the first to third ends of the first electronic switch are respectively a base, a collector and a collector of the triode. Shooting pole. The fan fault alarm circuit of claim 3, wherein the second electronic switch is a triode, and the first to third ends of the second electronic switch are respectively a base, a collector and a collector of the triode. Shooting pole. The fan fault alarm circuit of claim 3, wherein the first indicator module comprises a fourth resistor, a second transistor, a second capacitor and a first buzzer, and a cathode connection of the second transistor The DC power source, the anode of the second transistor is grounded through the second capacitor, and is further connected to the second end of the second electronic switch, the first end of the first buzzer is connected to the DC power source, and the second end is transmitted through The fourth resistor is coupled to the anode of the second transistor. The fan fault alarm circuit of claim 6, wherein the second rectifier circuit includes a fifth resistor and a third capacitor, and the first end of the fifth resistor is connected to the speed detecting pin of the fan controller. The second end is grounded through the third capacitor. The fan fault alarm circuit of claim 7, wherein the comparison circuit includes first and second operational amplifiers, and sixth to ninth resistors, wherein the non-inverting terminal of the first operational amplifier passes the sixth resistor and the The DC power supply is connected to the ground through the seventh resistor, and the inverting end of the first operational amplifier and the non-inverting end of the second operational amplifier are connected to the second end of the fifth resistor, and the first and second operational amplifiers are The output ends are connected to the second indicating circuit. The fan fault alarm circuit of claim 8, wherein the second indicating circuit comprises a tenth resistor, a third transistor, a fourth capacitor and a second buzzer, the cathode of the third transistor and the The DC power source is connected, the anode of the third transistor is grounded through the fourth capacitor, and is further connected to the output ends of the first and second operational amplifiers, the first end of the second buzzer is connected to the DC power source, and the second end The anode of the third transistor is connected through the tenth resistor.