TW201422921A - Control circuit for fan - Google Patents

Abstract

A control circuit for a fan include a working state detection module. The working state detection module is connected to an iBMC and a PSU to detect a working state of the iBMC and a server. When the server is not at work and the iBMC is at work, the working state detection module connects a power supply and the fan. When the server and the iBMC are not at work, the working state detection module disconnects the power supply and the fan. When the server is at work, the working state detection module disconnects the power supply and the fan.

Description

Fan control circuit

The invention relates to a fan control circuit.

In the conventional server design, we must use the management chip of the intelligent management platform of the Integrated Baseboard Management Controller (iBMC). The role of iBMC plays a more and more important role in the development of the server, so its power also has a certain increase. Therefore, it is necessary to design a reliable heat dissipation method for the iBMC to avoid the functional problem or damage of the iBMC due to heat dissipation problems.

In view of the above, it is necessary to provide a fan control circuit for dissipating heat for the iBMC.

A fan control circuit is disposed in a server, and the fan control circuit is configured to control a fan for dissipating heat for an integrated substrate management controller, the fan control circuit comprising:

A working state detecting module includes a reverse gate and a first electronic switch, and the two input ends of the reverse or gate are respectively connected to the integrated substrate management controller and the power supply to respectively receive the integrated substrate management controller a status signal and a system voltage of the power supply, the output of the reverse or gate being connected to the control end of the first electronic switch, the first end of the first electronic switch being connected to the power supply, and the second end of the first electronic switch The end is connected to the power pin of the fan;

When the server is in the non-working state and the integrated substrate management controller is in the working state, the power supply does not output the system voltage, the integrated substrate management controller outputs a low level state signal, and the inverse or gate outputs a high level signal. The first end of the first electronic switch is electrically connected to the second end to turn on the connection between the fan and the power source, and the fan starts to work;

When the server and the integrated substrate management controller are both in a non-operating state, the power supply does not output the system voltage, the integrated substrate management controller outputs a high level status signal, and the inverse or gate outputs a low level signal, The first end of the first electronic switch is disconnected from the second end to disconnect the fan from the power source, and the fan stops working;

When the server is in operation, the power supply outputs a system voltage, and the reverse or gate outputs a low level signal, and the first end and the second end of the first electronic switch are disconnected to disconnect the fan from the power source. The connection, the fan stops working.

The fan control circuit detects the working state of the server and the integrated substrate management controller through the working state detecting module. When the server is in a non-working state and the integrated substrate management controller is in an active state, the working state detecting module turns on the connection between the fan and the power source, and the fan starts to work to dissipate heat for the integrated substrate management controller; when the server and the integrated substrate When the management controller is in the non-working state, the working state detecting module disconnects the connection between the fan and the power source, and the fan stops working to save power; when the server is in the working state, the working state detecting module disconnects the fan. The connection to the power supply, the fan stops working to save power, and at this time, because the server is in operation, the integrated baseboard management controller can be dissipated by the server's system fan.

Referring to FIG. 1, the fan control circuit of the present invention is used to control a fan 2 that dissipates heat for an integrated baseboard management controller (iBMC) 1. The preferred embodiment of the fan control circuit includes a temperature detecting module 10, a working state detecting module 12, and a speed adjusting module 15.

The working state detecting module 12 is connected to the iBMC 1 and the power supply 16 for detecting the working state of the iBMC 1 and the server, and issuing a corresponding detecting signal. The working state detecting module 12 is configured to determine whether to output power to the fan 2 according to the detected status of the iBMC 1 and the server. The working state detecting module 12 is further connected to the temperature detecting module 10 and the speed adjusting module 15 to determine whether to output power to the temperature detecting module 10 and the speed adjusting module according to the detected state of the iBMC 1 and the power supply 16 15. The temperature detecting module 10 is configured to detect an ambient temperature near the iBMC 1. The temperature detecting module 10 is further connected to the speed adjusting module 15 to output a corresponding pulse signal to the speed adjusting module 15 according to the detected temperature value to control the speed of the fan 2.

Referring to FIG. 2, the working state detecting module 12 includes an inverse OR gate U2 and a field effect transistor Q3. An input of the inverse OR gate U2 is connected to the iBMC 1 to receive a status signal BMC_WORK_OK from the iBMC 1; the other input of the inverse OR gate U2 is connected to the power supply 16 to receive the system from the power supply 16 Voltage P3V3_SYS. The output of the inverse OR gate U2 is connected to the gate of the field effect transistor Q3. The source of the field effect transistor Q3 is connected to the dual voltage P3V3_AUX. The drain of the field effect transistor Q3 is used for the fan 2 and the temperature. The detection module 10 provides a voltage P3V3_S1. The dual voltage P3V3_AUX is provided by the system voltage P3V3_SYS or the standby voltage P3V3_STBY.

Referring to FIG. 3, the rotation speed adjustment module 15 includes three transistors Q1 and Q2. The base of the three-pole body Q2 is sequentially connected to the dual voltage P3V3_AUX through the resistors R2 and R1. The node and the temperature between the resistors R2 and R1 are detected. The measurement module 10 is connected. The emitter of the triode Q2 is grounded, and the collector is connected to the drain of the field effect transistor Q3 through a resistor R3. The collector of the triode Q2 is also directly connected to the base of the triode Q1. The emitter of the triode Q1 is grounded, and the collector of the triode Q1 passes through the resistor R4 and the drain of the field effect transistor Q3. Connected. The collector of the triode Q2 is also directly connected to the pulse pin PWM of the fan 2, and the power pin VCC of the fan 2 is connected to the drain of the field effect transistor Q3 to receive the voltage P3V3_S1, and the power supply of the fan 2 The pin VCC is also grounded through the capacitor C1; the ground pin GND of the fan 2 is grounded, and the speed pins TACH1 and TACH2 are connected to the temperature detecting module 10.

Referring to FIG. 4, the temperature detecting module 10 includes a temperature sensor U1. The voltage sensing pins VSEN2, VSEN4, VSEN6, and VSEN8 of the temperature sensor U1 are grounded through the thermistors TH1, TH2, TH3, and TH4, respectively. It is also grounded through capacitors C2 through resistors R5, R6, R7, and R8, respectively. The voltage sensing pins VSEN3 and VSEN5 of the temperature sensor U1 are grounded. The ground pin VREF of the temperature sensor U1 is grounded through the capacitor C2, and the other ground pin GND is directly grounded. The voltage pin 3VDD of the temperature sensor U1 is connected to the voltage P3V3_S1, and is also grounded through the capacitor C3. The capacitor C3 is connected in parallel with the capacitor C4. The voltage pin 3VSB of the temperature sensor U1 is connected to the voltage P3V3_S1, and is also grounded through the capacitor C5. The capacitor C5 is connected in parallel with the capacitor C6.

The pulse signal pin PWM of the temperature sensor U1 is connected to the node between the resistors R1 and R2 through the resistor R9. The fan control pin FAN1 of the temperature sensor U1 is connected to the speed pin TACH1 of the fan 2 through a resistor R10. The fan control pin FAN2 of the temperature sensor U1 is connected to the speed pin TACH2 of the fan 2 through a resistor R11. The temperature sensor U1 detects the change of the temperature by detecting the change of the voltage of the thermistors TH1-TH4, and then outputs the corresponding pulse signal.

The working principle of the above fan control circuit will be described below:

According to the principle of the power supply, when the servo is operating, the power supply 16 outputs the system voltage P3V3_SYS, and when the servo is not operating, the power supply 16 does not output the system voltage P3V3_SYS. The status signal BMC_WORK_OK output by the iBMC 1 is used to indicate the working status of the iBMC 1. When the iBMC 1 is in operation, the status signal BMC_WORK_OK output by the iBMC 1 is low, and the status output by the iBMC 1 when the iBMC 1 is not operating. The signal BMC_WORK_OK is high.

In this embodiment, the temperature sensor U1 is disposed around the iBMC 1 to detect the temperature of the iBMC 1.

When the server is powered and the server is not working, the iBMC 1 will start to work. At this time, if the iBMC 1 is working normally, the output status signal BMC_WORK_OK is low, and the power supply 16 does not output the system voltage P3V3_SYS. That is, both inputs of the inverse OR gate U2 receive a low level signal. After the inverse or gate U2 processing, a high level signal is output, that is, the gate of the field effect transistor Q3 receives a high level signal. The field effect transistor Q3 is turned on, that is, the standby voltage P3V3_STBY will supply power to the temperature detecting module 10 and the fan 2 through the field effect transistor Q3. At this time, the temperature detecting module 10 starts to detect the temperature around the iBMC 1, and outputs a corresponding pulse signal to the speed adjusting module 15 according to the detected temperature value, so as to adjust the rotation speed of the fan 2, and the fan 2 The speed signal will feed the speed of the fan 2 to the temperature detecting module 10 through the speed pins TACH1 and TACH2. The temperature detecting module 10 corrects the speed of the fan 2 according to the speed signal received by the fan 2. The speed adjustment module 15 outputs a voltage value corresponding to the magnitude according to the received pulse signal, thereby adjusting the rotation speed of the fan 2.

If iBMC 1 is not working, the status signal BMC_WORK_OK output by iBMC 1 is high. At this time, the output terminal of the inverse OR gate U2 outputs a low level signal, the field effect transistor Q3 is turned off, and the fan 2 is not powered. That is, when the iBMC 1 is not working, the fan 2 stops working to avoid wasting power.

When the server starts to work, the system fan of the server will start to work, and the power supply 16 outputs the system voltage P3V3_SYS, that is, one of the inputs of the reverse OR gate U2 receives a high level voltage. At this time, regardless of whether the iBMC 1 is working, that is, regardless of whether the status signal BMC_WORK_OK output by the iBMC 1 is high level or low level, the OR gate U5 outputs a low level signal, that is, the field effect transistor Q3 is turned off, and the fan 2 is not allowed. Electricity. At this time, the reason why the fan 2 does not work is that the iBMC 1 can be dissipated through the system fan, so that the temperature of the iBMC 1 is not too high, and the electric energy can be saved as much as possible.

The fan control circuit detects the working state of the iBMC 1 and the entire server system through the working state detecting module 12, and correspondingly selects whether to turn on the fan 2. Specifically, when the server is not working and the iBMC 1 is working, the fan 2 is turned on to dissipate the iBMC 1; when the server is not working and the iBMC 1 is not working, the fan 2 is turned off to save power; when the server is When working, no matter whether the iBMC 1 is working or not, the fan 2 is turned off to save power. As for the heat dissipation of the iBMC 1, the system fan is responsible. As such, the iBMC 1 will not overheat due to work before the system is turned on.

As can be seen from the above description, the speed adjustment module 15 and the temperature detection module 10 can be deleted, that is, only the working state detection module 12 detects the working state of the iBMC 1 and the server to control whether the fan 2 works, and The rotation speed of the fan 2 is adjusted correspondingly without considering the temperature of the iBMC 1. In the present embodiment, the triodes Q1 and Q2 and the field effect transistor Q3 both function as electronic switches. In other embodiments, the triodes Q1 and Q2 and the field effect transistor Q3 can also be used by other electrons. Replaced by a switch, wherein the base, the emitter and the collector of the triode Q1 respectively correspond to the control end, the first end and the second end of the electronic switch, and the gate, the source and the drain of the field effect transistor Q3 Corresponding to the control end, the first end and the second end of the electronic switch respectively.

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.

1. . . iBMC

2. . . fan

10. . . Temperature detection module

12. . . Work status detection module

15. . . Speed adjustment module

16. . . Power Supplier

R1-R11. . . resistance

U2. . . Reverse or gate

Q1, Q2. . . Triode

Q3. . . Field effect transistor

U1. . . Temperature sensor

C1-C6. . . capacitance

TH1-TH3. . . Thermistor

1 is a block diagram of a preferred embodiment of a fan control circuit of the present invention.

2-4 are circuit diagrams of the fan control circuit of FIG. 1.

1. . . iBMC

2. . . fan

10. . . Temperature detection module

12. . . Work status detection module

15. . . Speed adjustment module

16. . . Power Supplier

Claims (8)

A fan control circuit is disposed in a server, and the fan control circuit is configured to control a fan for dissipating heat for an integrated substrate management controller, the fan control circuit comprising:
A working state detecting module includes a reverse gate and a first electronic switch, and the two input ends of the reverse or gate are respectively connected to the integrated substrate management controller and the power supply to respectively receive the integrated substrate management controller a status signal and a system voltage of the power supply, the output of the reverse or gate being connected to the control end of the first electronic switch, the first end of the first electronic switch being connected to the power supply, and the second end of the first electronic switch The end is connected to the power pin of the fan;
When the server is in the non-working state and the integrated substrate management controller is in the working state, the power supply does not output the system voltage, the integrated substrate management controller outputs a low level state signal, and the inverse or gate outputs a high level signal. The first end of the first electronic switch is electrically connected to the second end to turn on the connection between the fan and the power source, and the fan starts to work;
When the server and the integrated substrate management controller are both in a non-operating state, the power supply does not output the system voltage, the integrated substrate management controller outputs a high level status signal, and the inverse or gate outputs a low level signal, The first end of the first electronic switch is disconnected from the second end to disconnect the fan from the power source, the fan stops working; and when the server is in operation, the power supply outputs a system voltage, the reverse The gate outputs a low level signal, and the first end of the first electronic switch is disconnected from the second end to disconnect the fan from the power source, and the fan stops working. The fan control circuit of claim 1, wherein the first electronic switch is a field effect transistor, and the gate, the source and the drain of the field effect transistor respectively correspond to the control end of the first electronic switch, First end and second end. The fan control circuit of claim 1, further comprising:
A temperature detecting module is connected to the integrated substrate management controller and the working state detecting module. When the server is in a non-working state and the integrated substrate management controller is in a working state, the working state detecting module further turns on the fan and the temperature detecting Detecting the connection between the modules, so that the temperature detecting module starts detecting the temperature of the integrated substrate management controller, the temperature detecting module outputs a corresponding pulse signal according to the detected temperature value; and a speed adjusting circuit is connected to The integrated substrate management controller and the fan are configured to adjust the rotation speed of the fan according to the pulse signal output by the temperature detection module. The fan control circuit of claim 3, wherein the speed adjustment circuit comprises second and third electronic switches, the control end of the second electronic switch is connected to the temperature detecting module, and the second electronic switch is One end of the second electronic switch is connected to the working state detecting module through a first resistor, and the second end of the second electronic switch is directly connected to the control end of the third electronic switch, the third The first end of the electronic switch is grounded, and the second end of the third electronic switch is connected to the working state detecting module through a second resistor. The second end of the third electronic switch is also directly connected to the control pin of the fan. The fan control circuit of claim 4, wherein the second electronic switch is a triode, and the base, the emitter and the collector of the triode respectively correspond to the control end of the second electronic switch, First end and second end. The fan control circuit of claim 4, wherein the third electronic switch is a triode, and the base, the emitter and the collector of the triode respectively correspond to the control end of the third electronic switch, First end and second end. The fan control circuit of claim 4, wherein the temperature detecting module is further connected to the speed pin of the fan to receive the speed signal of the fan, and adjust the output pulse signal according to the received speed signal. To adjust the speed of the fan. The fan control circuit of claim 7, wherein the temperature detecting module comprises a temperature sensor, and the first to fourth voltage sensing pins of the temperature sensor respectively pass through the first to fourth heats. The varistor is grounded and grounded through the third to sixth resistors respectively through the first capacitor; the fifth and sixth voltage sensing pins of the temperature sensor are grounded; the first ground pin of the temperature sensor is transmitted through The second capacitor is grounded, and the second ground pin is directly grounded; the first voltage pin of the temperature sensor is connected to the second end of the first electronic switch, and the first voltage pin of the temperature sensor is also passed through the third The capacitor is grounded; the second voltage pin of the temperature sensor is connected to the second end of the first electronic switch, and the second voltage pin of the temperature sensor is also grounded through the fourth capacitor; the pulse of the temperature sensor The signal pin is connected to the control end of the second electronic switch through the seventh resistor; the first fan control pin of the temperature sensor is connected to the first speed pin of the fan through the eighth resistor, and the temperature sensor is Two fan control pins through the ninth The resistor is connected to the second speed pin of the fan.