Fan control signal switching circuit

Abstract

The utility model relates to the technical field of servers, in particular to a fan control signal switching circuit, which is characterized in that two signal paths are constructed by using discrete components, and a field-effect tube switch and a negation field-effect tube switch are arranged on the signal paths; meanwhile, a control circuit is designed to control the output potential of the switch on the signal channel and the output potential of the negation field effect transistor switch, and therefore switching of fan control signals is achieved. Control signal switching of the fan is achieved through the discrete circuit, compared with integrated circuits such as a logic chip or a digital chip, the discrete circuit is low in price, and the manufacturing cost of equipment can be effectively reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of servers, and in particular relates to a fan control signal switching circuit. Background Art

[0002] In storage server equipment, fans are essential cooling devices, and their operating status directly affects the stability and service life of the equipment. The control signal switching problem of fans is an important research direction in the field of fan control technology. It involves how to adjust the fan speed in real time according to factors such as the working status of the equipment and the ambient temperature to achieve the best cooling effect.

[0003] In the existing technology, BMC is usually used to realize the control signal output of the fan. BMC can automatically adjust the output control signal according to the working status of the equipment and the ambient temperature through the built-in program, so as to realize the precise control of the fan. In addition, there are some solutions that use logic circuit chips or digital circuit chips to realize the control signal switching of the fan. These solutions usually require complex circuit design and high-precision electronic components, which are more expensive, but can achieve higher control accuracy and smoother switching effect.

[0004] However, there are still some problems with the existing fan control technology in practical applications. First, the price of integrated circuits such as logic chips or digital chips is relatively high, which increases the manufacturing cost of the equipment. Secondly, the life cycle of storage server equipment is relatively long. Once such chips are discontinued, it may lead to product board changes, affecting the normal production and supply of the equipment. In addition, these integrated circuits have high power consumption, which is not conducive to energy saving and environmental protection of the equipment. Finally, due to the complex internal structure of these integrated circuits and the high failure rate, the operating reliability of the fan may be affected. Therefore, how to realize the control signal switching of the fan through discrete circuits to improve the reliability of fan control is an important problem facing current technology. Utility Model Content

[0005] In view of the above-mentioned deficiencies in the prior art, the utility model provides a fan control signal switching circuit to solve the above-mentioned technical problems.

[0006] The utility model provides a fan control signal switching circuit, comprising:

[0007] a first signal input terminal, wherein the first signal input terminal is connected to the gate of a first switch, the source of the first switch is electrically connected to a first pull-up power supply, and the drain of the first switch is grounded; the first pull-up power supply is electrically connected to the gate of a first inversion switch, the source of the first inversion switch is connected to a second pull-up power supply, the drain of the first inversion switch is grounded, and the second pull-up power supply is connected to the signal output terminal;

[0008] The first pull-up power source is connected to the source of the first control switch, the gate of the first control switch is connected to the fourth pull-up power source and the control signal input terminal respectively, and the drain of the first control switch is grounded;

[0009] a second signal input terminal, wherein the second signal input terminal is connected to the gate of a second switch, the source of the second switch is electrically connected to a third pull-up power supply, and the drain of the second switch is grounded; the third pull-up power supply is connected to the gate of a second inversion switch, the gate of the second inversion switch is connected to an output circuit, and the output circuit is a connection circuit between the second pull-up power supply and the signal output terminal;

[0010] The control signal input terminal is connected to the gate of the second control switch, the source of the second control switch is connected to the fifth pull-up power supply, and the drain of the second control switch is grounded; the fifth pull-up power supply is also connected to the gate of the third control switch, the source of the third control switch is connected to the third pull-up power supply, and the drain of the third control switch is grounded;

[0011] The first switch, the first inverting switch, the second switch, the second inverting switch, the first control switch, the second control switch and the third control switch all adopt field effect tubes.

[0012] In an optional implementation, the signal output end is connected to a fan controller.

[0013] In an optional implementation, the first signal input end is connected to a first pin of the BMC; and the second signal input end is connected to a second pin of the BMC.

[0014] In an optional implementation, the first signal input terminal is connected to a first pin of the BMC via a twisted pair cable; and the second signal input terminal is connected to a second pin of the BMC via a twisted pair cable.

[0015] In an optional implementation, the control signal input terminal is connected to a complex programmable logic device.

[0016] In an optional implementation, the complex programmable logic device is connected to the fan controller via an I2C line.

[0017] In an optional implementation, the fan controller is electrically connected to a driving motor and a rotation speed sensor of the fan, respectively, and the rotation speed sensor detects the rotation speed of the fan.

[0018] In an optional implementation, the complex programmable logic device is connected to the BMC via an I2C bus.

[0019] In an optional implementation, a first resistor is connected in series between the first signal input terminal and the gate of the first switch.

[0020] In an optional implementation, a second resistor is connected in series between the second signal input terminal and the gate of the second switch.

[0021] The beneficial effect of the utility model is that the fan control signal switching circuit provided by the utility model adopts a discrete circuit to realize the control signal switching of the fan. Compared with the use of integrated circuits such as logic chips or digital chips, the price of discrete circuits is lower, which can effectively reduce the manufacturing cost of the equipment. The design of the circuit is relatively simple, the failure rate is low, and the reliability of fan control can be improved. This is of great significance for ensuring the stable operation of the equipment and extending the service life of the equipment.

[0022] In addition, the utility model has a reliable design principle, a simple structure and a very broad application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 It is a schematic diagram of a fan control signal switching circuit according to an embodiment of the utility model. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0027] In order to facilitate the understanding of the present invention, the fan control signal switching circuit provided by the present invention is further described below based on the principle of the fan control signal switching circuit of the present invention and in combination with embodiments.

[0028] For details, please refer to Figure 1 , the fan control signal switching circuit includes:

[0029] A first signal input terminal, the first signal input terminal is connected to the gate of the first switch Q11, the source of the first switch Q11 is electrically connected to the first pull-up power supply, and the drain of the first switch Q11 is grounded; the first pull-up power supply U1 is electrically connected to the gate of the first inverting switch Q12, the source of the first inverting switch Q12 is connected to the second pull-up power supply U2, the drain of the first inverting switch Q12 is grounded, and the second pull-up power supply U2 is connected to the signal output terminal;

[0030] The first pull-up power source U1 is connected to the source of the first control switch Q31, the gate of the first control switch Q31 is respectively connected to the fourth pull-up power source U4 and the control signal input terminal, and the drain of the first control switch Q31 is grounded;

[0031] A second signal input terminal, the second signal input terminal is connected to the gate of the second switch Q21, the source of the second switch Q21 is electrically connected to the third pull-up power supply U3, and the drain of the second switch Q21 is grounded; the third pull-up power supply U3 is connected to the gate of the second inverting switch Q22, and the gate of the second inverting switch Q22 is connected to the output line, and the output line is a connection line between the second pull-up power supply U2 and the signal output terminal;

[0032] The control signal input terminal is connected to the gate of the second control switch Q32, the source of the second control switch Q32 is connected to the fifth pull-up power supply U5, and the drain of the second control switch Q32 is grounded; the fifth pull-up power supply U5 is also connected to the gate of the third control switch Q33, the source of the third control switch Q33 is connected to the third pull-up power supply U3, and the drain of the third control switch Q33 is grounded;

[0033] The first switch Q11, the first inverting switch Q12, the second switch Q21, the second inverting switch Q22, the first control switch Q31, the second control switch Q32 and the third control switch Q33 all use field effect tubes, model H7N0308LS.

[0034] The signal output end is connected to the fan controller. The first signal input end is connected to the first pin of the BMC; the second signal input end is connected to the second pin of the BMC. The first signal input end is connected to the first pin of the BMC through a twisted pair cable; the second signal input end is connected to the second pin of the BMC through a twisted pair cable. The output signal of the first pin of the BMC is FAN4_BMC_PWM1, and the output signal of the second pin of the BMC is FAN4_BMC_PWM2.

[0035] The control signal input terminal is connected to a complex programmable logic device (CPLD).

[0036] A first resistor is connected in series between the first signal input terminal and the gate of the first switch. A second resistor is connected in series between the second signal input terminal and the gate of the second switch.

[0037] When the control signal CPLD_FAN_PWM_R_SW input to the CPLD is low level 0, the first control switch Q31 is turned off, and its D pole is in a high-impedance state, and the first control switch Q31 will not affect the output state of the first switch Q11; if the G pole input FAN4_BMC_PWM1 of the first switch Q11 is low level 0, the first switch Q11 is turned off, and the D pole of the first switch Q11 is in a high-impedance state, and due to the pull-up of the first pull-up power supply U1, a high level 1 is output to the first inverting switch Q12; if the G pole input signal FAN4_BMC_PWM1 of the first switch Q11 is high level 1, the first switch Q11 is turned on, and its D pole is in a grounded state, and a low level 0 is output to the first inverting switch Q12.

[0038] When the G-pole input signal CPLD_FAN_PWM_R_SW of the first control switch Q31 is at high level 1, the first control switch Q31 is turned on, its D-pole is grounded, and the input of the first bar switch Q12 remains at low level 0 and is not affected by the FAN4_BMC_PWM1 signal.

[0039] The specific correspondence relationship of the first group of signal levels is shown in Table 1:

[0040] Table 1

[0041]

[0042] When the G-pole input signal CPLD_FAN_PWM_R_SW of the second control switch Q32 is at a low level 0, the second control switch Q32 is turned off, and its D-pole outputs a high level 1 due to the pull-up of the fifth pull-up power supply, thereby turning on the third control switch Q33, and the D-pole of the third control switch Q33 is grounded, and the output of the second switch Q21 remains at a low level 0, and is not affected by the input signal FAN4_BMC_PWM2 of the second signal input terminal.

[0043] When the input signal CPLD_FAN_PWM_R_SW of the second control switch Q32 is high level 1, the second control switch Q32 is turned on, and its D pole is grounded, so that the third control switch Q33 is turned off, and its D pole is in a high impedance state; at this time, if the G pole input signal FAN4_BMC_PWM2 of the second switch Q21 is low level 0, the second switch Q21 is turned off, and its D pole is in a high impedance state, and due to the pull-up effect of the third pull-up power supply, a high level 1 is output to the second inverting switch; if the G pole input signal FAN4_BMC_PWM2 of the second switch Q21 is high level 1, the second switch Q21 is turned on, and its D pole is grounded, and a low level 0 is output to the second inverting switch.

[0044] The second switch Q21 is input to the G pole of the second bar switch Q22 , and an opposite level signal is generated at the D pole of the second bar switch Q22 .

[0045] The level correspondence table of the second group of signals is shown in Table 2:

[0046] Table 2

[0047]

[0048] The level comparison table of the final output signal is shown in Table 3:

[0049] Table 3

[0050]

[0051] The following goals can be achieved through the above logic:

[0052] When the CPLD_FAN_PWM_R_SW input is low level 0, the FAN4_BMC_PWM_CONN output is the same as FAN4_BMC_PWM1; when the CPLD_FAN_PWM_R_SW input is high level 1, the FAN4_BMC_PWM_CONN output is the same as FAN4_BMC_PWM2. This achieves the purpose of switching the PWM1 / 2 signal with the SW signal.

[0053] Specifically, the level comparison table of the control signal and the output signal is shown in Table 4:

[0054] Table 4

[0055]

[0056] The pull-up power supplies in the circuit all use 3V3 power supplies.

[0057] In another embodiment, the complex programmable logic device is connected to the fan controller via an I2C line. The fan controller is electrically connected to the drive motor and the speed sensor of the fan respectively, and the speed sensor detects the fan speed. The complex programmable logic device is connected to the BMC via the I2C bus.

[0058] After receiving the control signal output from the signal output terminal, the fan controller adjusts the speed of the drive motor and receives the actual speed collected by the speed sensor. The fan controller transmits the actual speed to the complex programmable logic device through the I2C line, and the complex programmable logic device uploads the actual speed to the BMC through the I2C line. After receiving the fan control signal, the fan controller sends a response prompt signal to the CPLD. After sending the fan control signal, the BMC sends a prompt signal to the CPLD synchronously. If the CPLD only receives the prompt signal from the BMC but not the prompt signal from the fan controller, it sends a control signal to the control signal input terminal.

[0059] The fan control signal switching circuit in this embodiment has the following beneficial effects:

[0060] 1. Reduce costs: This technical solution uses discrete circuits to achieve fan control signal switching. Compared with using integrated circuits such as logic chips or digital chips, discrete circuits are cheaper and can effectively reduce the manufacturing cost of the equipment.

[0061] 2. Improve reliability: The design of discrete circuits is relatively simple, with a low failure rate, which can improve the reliability of fan control. This is of great significance for ensuring the stable operation of the equipment and extending the service life of the equipment.

[0062] 3. Reduce design complexity: This technical solution adopts discrete circuits, avoiding complex circuit design and high-precision electronic components, reducing design complexity, and helping to improve design efficiency and quality.

[0063] 4. Avoid product board changes: Since the production cycle of discrete circuits is short and it is not easy to stop production, it can effectively avoid the problem of product board changes due to integrated circuit supply risks, and ensure the normal production and supply of equipment.

[0064] 5. Energy saving and environmental protection: The discrete circuit has low power consumption, which is beneficial to the energy saving and environmental protection of the equipment, and meets the current social demand for green technology.

[0065] Although the present invention is described in detail by referring to the accompanying drawings and in combination with the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person skilled in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person skilled in the art who is familiar with the present technical field may easily think of changes or substitutions within the technical scope disclosed in the present invention, and these shall be within the scope of protection of the present invention.

Claims

1. A fan control signal switching circuit, characterized in that: include: a first signal input terminal, wherein the first signal input terminal is connected to the gate of a first switch, the source of the first switch is electrically connected to a first pull-up power supply, and the drain of the first switch is grounded; the first pull-up power supply is electrically connected to the gate of a first inversion switch, the source of the first inversion switch is connected to a second pull-up power supply, the drain of the first inversion switch is grounded, and the second pull-up power supply is connected to the signal output terminal; The first pull-up power source is connected to the source of the first control switch, the gate of the first control switch is connected to the fourth pull-up power source and the control signal input terminal respectively, and the drain of the first control switch is grounded; a second signal input terminal, wherein the second signal input terminal is connected to the gate of a second switch, the source of the second switch is electrically connected to a third pull-up power supply, and the drain of the second switch is grounded; the third pull-up power supply is connected to the gate of a second inversion switch, the gate of the second inversion switch is connected to an output circuit, and the output circuit is a connection circuit between the second pull-up power supply and the signal output terminal; The control signal input terminal is connected to the gate of the second control switch, the source of the second control switch is connected to the fifth pull-up power supply, and the drain of the second control switch is grounded; the fifth pull-up power supply is also connected to the gate of the third control switch, the source of the third control switch is connected to the third pull-up power supply, and the drain of the third control switch is grounded; The first switch, the first inverting switch, the second switch, the second inverting switch, the first control switch, the second control switch and the third control switch all adopt field effect tubes.

2. The fan control signal switching circuit according to claim 1, characterized in that: The signal output end is connected to a fan controller.

3. The fan control signal switching circuit according to claim 1, characterized in that: The first signal input end is connected to a first pin of the BMC; and the second signal input end is connected to a second pin of the BMC.

4. The fan control signal switching circuit according to claim 3, characterized in that: The first signal input end is connected to a first pin of the BMC through a twisted pair cable; and the second signal input end is connected to a second pin of the BMC through a twisted pair cable.

5. The fan control signal switching circuit according to claim 1, characterized in that: The control signal input terminal is connected to a complex programmable logic device.

6. The fan control signal switching circuit according to claim 5, characterized in that: The complex programmable logic device is connected to the fan controller via an I2C line.

7. The fan control signal switching circuit according to claim 6, characterized in that: The fan controller is electrically connected to a driving motor and a rotation speed sensor of the fan respectively, and the rotation speed sensor detects the rotation speed of the fan.

8. The fan control signal switching circuit according to claim 7, characterized in that: The complex programmable logic device is connected to the BMC via an I2C bus.

9. The fan control signal switching circuit according to claim 1, characterized in that: A first resistor is connected in series between the first signal input terminal and the gate of the first switch.

10. The fan control signal switching circuit according to claim 1, characterized in that: A second resistor is connected in series between the second signal input terminal and the gate of the second switch.

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