CN102506025B - 12V direct-current air cooling control module - Google Patents

Abstract

The invention discloses a 12V DC air-cooled control module, and aims to provide a 12V DC air-cooled control module to realize monitoring and random control of fan speed, save energy consumption and reduce noise. The invention consists of a backplane connector, a hot-swappable circuit, a filter decoupling circuit, a high-frequency pulse width modulation (PWM) control circuit, and a fan connector. The hot-swappable circuit is composed of a filter, a first voltage divider, and a current-sensing resistor. , hot-swappable controller, timer, second voltage divider and switch tube; filter decoupling circuit is composed of public filter and 4 shunt filters; high frequency pulse width modulation control circuit is composed of pulse width modulation controller And signal level preset circuit. The invention can realize the monitoring and arbitrary control of the fan speed, and can realize hot plugging, replacement and other operations of the fan, save a lot of electric energy, greatly reduce noise, improve the service life of the fan, and save system operating costs.

Description

A 12V DC air-cooled control module

technical field

The invention relates to an air-cooled control module, in particular to a 12V DC air-cooled control module.

Background technique

With the increasing power density of high-performance computers, it is an important research content of high-performance computer system cooling technology to reduce the electrical power of supporting cooling facilities and improve the overall energy efficiency of the whole system while realizing efficient and reliable heat dissipation of computer systems. The forced air cooling heat dissipation technology has been used for a long time because of its simple process, low cost and remarkable heat dissipation effect. With the improvement of assembly density and the change of power supply scheme, the demand for wind pressure and air volume is increasing, and the demand for the number of fans is increasing. This creates additional problems: power consumption increases dramatically, and the noise becomes increasingly unbearable. In addition, since the heat dissipation of the system itself adopts a redundant design, the above problems are particularly prominent when the workload of the system is not very large. However, many large-scale systems often have a small workload most of the time, and the processor usage rate is not high. At this time, the air-cooled system is inefficient. How to solve this problem must be studied deeply in the current and future development of high-performance computer systems.

Many large-scale data systems often adopt the structure of "backplane + plug-in module". The air-cooled module is also produced based on this module plug-in structure. When replacing and maintaining the fan module, it must be plugged and unplugged without affecting the system work. . When the circuit is powered on or hot-plugged, there will be a large starting current and voltage fluctuations. These phenomena will affect the normal operation of other plug-in modules, and even cause damage to the entire system.

Due to the needs of energy saving and noise reduction, it is necessary to adjust the wind speed of the fan online according to the load temperature and system operating load. Since high-performance computers generally run without stopping, the fans used must have live maintenance and replacement functions. The fan power supply voltage is generally taken from the common bus voltage, but its current often causes great interference and often causes great damage to other power supply circuits. This has occurred in previous supercomputer systems, and this situation must be resolved. The previous fan control technology, whether using simple switch control or linear control, or low-frequency pulse width modulation technology only for fan speed regulation, cannot completely solve the interference impact of fan current on bus voltage, high noise, high power loss, fan Problems such as low lifespan and no monitoring and control of fan speed.

At present, there is no 12V DC air-cooled control module product in the domestic market. Some foreign DC air-cooled control modules have high working voltage, mostly designed for 24V, 48V or even higher voltage, and the maximum working current load capacity can only reach 6A; and often only include fan control circuit design, some products include heat There is no 12V air-cooled module including hot-swappable, filter decoupling, and fan control for plug-in circuits, and the existing product structure uses cable connection for external connections, which is not suitable for backplane structure and centralized DC bus power supply way of data systems.

Contents of the invention

The technical problem to be solved by the present invention is: in order to completely solve the interference impact of the fan current on the bus voltage, high noise, high power loss, and low fan life that cannot be completely solved by simple switch control, linear control, low-frequency pulse width modulation and other technologies , Insufficient fan monitoring and control, etc., the present invention provides a 12V DC air-cooled control module, which realizes the monitoring and arbitrary control of the fan speed to save energy consumption and reduce noise, and at the same time realizes operations such as live plugging and replacement of the fan module , and share the 12V DC bus with other circuits in the data system without negative impact, and improve the service life of the fan. And the load capacity of the air-cooled control module is not less than 20A.

In order to achieve the above object, the present invention adopts the following technical solutions:

The 12V DC air-cooling control module of the present invention is installed in a subframe providing cooling service in a high-performance computer system cabinet, and is connected with the backboard of the computer. The invention is composed of a backplane connector, a hot plug circuit, a filter decoupling circuit, a high-frequency pulse width modulation (PWM) control circuit, and a fan connector, all of which are integrated on one printed circuit board. The present invention is connected with the system backplane through the backplane connector, and the present invention is connected with the fan group through the fan connector.

The backplane connector adopts a commercial connector (such as FCI's product number 51700), which requires a load current capacity of no less than 20A and no less than 6 signal pins. The backplane connector is connected with the backplane of the computer system, the internal hot-swap controller of the present invention, and the high-frequency pulse width modulation control circuit, and provides 12V DC power supply, 3.3V DC power supply, ground, signal, etc. for other components of the present invention Electrical transmission and connection; the backplane connector provides a channel for the system monitoring unit (monitor and control unit hereinafter referred to as MCU) to monitor and control the fan group connected to the present invention.

The hot-swapping circuit is connected with the backplane connector and the filter decoupling circuit to provide the present invention with functions of overcurrent protection, overvoltage protection, undervoltage protection, power-on slow start, and live plugging and unplugging, eliminating the need for 12V DC air-cooled control modules to The impact and interference on the bus voltage during electric starting and hot plugging. The hot-swap circuit is composed of a filter, a first voltage divider, a current-sensing resistor, a hot-swap controller, a timer, a second voltage divider and a switch tube. The filter is connected to the backplane connector, the first voltage divider, and the current-sensing resistor. It is composed of a conventional RC filter circuit connected in parallel with the first diode. The RC filter circuit uses a 10Ω resistor and a 0.1μf/25V Capacitors are connected in series, the resistance of the RC circuit and the first diode are connected to the backplane connector, the first voltage divider, and the current detection resistor, and the other ends of the first diode and the capacitor of the RC circuit are connected to the ground. Both the first voltage divider and the second voltage divider are composed of the first voltage divider resistor and the second voltage divider resistor connected in series, which meet the current limit of less than 10μA and realize the start-up threshold design of 10.8V at the same time. During design, the optional first voltage dividing resistor is 60.4kΩ, and the second voltage dividing resistor is 8.45kΩ. The first voltage divider is externally connected to the backplane connector, and internally connected to the hot-swap controller, filter, and current-sensing resistor. The first voltage dividing resistor of the first voltage divider is connected with the backplane connector, the current detection resistor and the filter, and the second voltage dividing resistor is connected with the hot swap controller. The second voltage divider is connected with the hot-swappable controller, the switch tube, and the filter decoupling circuit; the first voltage divider resistor of the second voltage divider is connected with the switch tube and the filter decoupling circuit; The voltage divider resistor is connected to the hot-swap controller. The current-sensing resistor is a 0.002Ω/3W resistor, which is externally connected to the backplane connector and internally connected to the switch tube, hot-swap controller, filter, and the first voltage divider. The hot-swap controller is connected with the first voltage divider, current-sensing resistor, switch tube, second voltage divider, and timer. It adopts a commercial hot-swap controller with an operating voltage of ≥12V and an operating temperature of 0-70°C. , With current detection function, it also has over-current protection, over-voltage protection, under-voltage protection, and timing start function. The timer is connected to the hot-swap controller and consists of a first capacitor of lnf/50V and a second capacitor of 22nf/50V. One end of the two capacitors is connected to the hot-swap controller, and the other end is grounded. One capacitor is used to set the fault protection time, and the second capacitor is used to set the startup time. The switch tube is connected with the current-sensing resistor, the hot-swap controller, the second voltage divider and the filter decoupling circuit, and adopts N-MOS with a working voltage of 30V, a working current ≥ 50A, and a conduction resistance R _DS ≤ 0.01Ω.

The filter decoupling circuit is connected with the hot-swappable circuit and the fan connector, and is composed of a two-stage LC filter circuit. The filter, ... the L split filter, ... the N split filter are connected; the second stage is composed of the first split filter, ... the L split filter, ... the N split filter They are connected to the public filter and the fan connector respectively. N is the number of fans in a single fan subrack, which depends on the cooling design and structural design of the computer system. Currently, it is generally less than or equal to 6, and N≥L≥1. The public filter uses a traditional LC filter circuit. The LC filter circuit of the public filter requires an inductance > 500nH, a rated current > 20A, a capacitor capacity > 2.8mf, and a withstand voltage > 16V. The N shunt filters are all composed of a traditional LC filter circuit connected in parallel with a diode. The inductance used in the LC filter circuit in each shunt filter is required to meet the inductance > 10μH, rated current > 4A, and the capacitor used requires a total capacity. > 2.3mf, withstand voltage > 16V, the second diode used requires a withstand voltage of 75V and a forward conduction current of 0.2A. The filter decoupling circuit greatly weakens the interference of the working current of the fan on the 12V bus voltage of the backplane.

The high-frequency pulse width modulation control circuit is connected with the backplane connector and the fan connector, and is composed of a pulse width modulation controller (PWM controller) and a signal level preset circuit. The PWM controller is connected with the signal level preset circuit, the backplane connector and the fan connector, and the signal level preset circuit is connected with the PWM controller and the backplane connector. The PWM controller is a commercial controller with a communication bus, no less than N channels of PWM output, N channels of TACH input channels, and a single address line. The output PWM signal frequency can work at >20KHz and can be set by the user. The PWM signal and the TACH signal of the PWM controller are respectively connected to the PWM signal lines and the TACH signal lines of the N fans through the fan connector. The SCL pin, SDA pin, FSPEED pin and ALERT pin of the PWM controller are connected to the backplane connector to realize communication with the system MCU. The PWM controller accepts the read/write operation commands sent by the system MCU according to the temperature collection in the system, the statistics of the workload of the system and the results of the system idle state query through the backplane connector, so as to adjust the wind speed of the fan; at the same time Report the status and speed information of the fan to the system MCU through the communication bus through the backplane connector. The PWM controller accepts the MCU's write operation to its configuration register through the backplane connector, and sets the pulse width modulation frequency to 22.5KHz. The VCC pin and GND pin of the PWM controller are connected to the backplane through the backplane connector to obtain power. The signal level preset circuit is composed of 2N+4 resistors connected in parallel. Among them, one end of the two 2.2kΩ resistors is connected to the PWM controller, and the other end is connected to the backplane connector to realize the preset values of the clock signal SCL and the data signal SDA. One end of two 10kΩ resistors is connected to the PWM controller, and the other end is connected to the backplane connector to realize the preset value of the interrupt/alarm signal ALERT and the wind speed setting signal FSPEED. One end of 2N 2.2kΩ resistors is connected to the fan connector, and the other end is connected to the backplane connector to realize the preset values of N PWM signals and N TACH signals.

The fan connector is connected with the filter decoupling circuit, the high-frequency pulse width modulation control circuit, and the fan group, and is composed of N 4-core commercial connectors connected in parallel. The fan connector requires the load capacity of each pin to be >5A.

The number of fans used in the entire high-performance computing system may be M (thousands or even tens of thousands). At this time, the number of the present invention must be increased to meet the requirements for controlling all fans, and the number of using the present invention is M/N.

When the 12V DC air-cooled control module of the present invention is initially powered on, the hot-swappable controller of the hot-swappable circuit detects the voltage of the current-sensing resistor. The potential of the voltage divider and the second voltage divider is detected, and if the voltage is greater than 10.8V, the functions of overvoltage protection and undervoltage protection are realized. It achieves the purpose of providing power-on protection and slow power-on for the entire 12V air-cooled module, and at the same time provides protection for the 12V bus voltage on the backplane when the fan fails. When the present invention works normally, the filter decoupling circuit receives the voltage ripple generated by the fan group from the fan connector, successively passes through the absorption of the shunt filter and the common filter, and finally feeds back to the 12V bus on the backplane and the voltage ripple on the ground. Interference is greatly reduced. The high-frequency pulse width modulation control circuit receives the fan group speed signal transmitted from the fan connector from time to time, and maintains communication with the system MCU through the backplane connector. The invention regularly transmits the rotation speed information to the system MCU through the backboard, and receives the writing operation of the system MCU through the backplane according to the system operation status and temperature conditions, and commands the PWM controller to complete the operation of increasing or decreasing the speed of the fan group. When the PWM controller receives an instruction to increase the speed, it will increase the duty cycle of its output PWM signal to speed up the fan speed; when the PWM controller receives an instruction to decrease the speed, it will reduce the duty cycle of its output PWM signal , making the fan speed slow down.

Adopt the present invention can reach following technical effect:

1. The present invention perfectly realizes the task of guaranteeing the operating environment of the high-efficiency computer system, ensures the safe, stable and reliable operation of the system, and at the same time realizes the optimal adjustment of the fan speed, saves a lot of electric energy, and greatly reduces the noise. It also improves the service life of the fan and saves the operating cost of the system. The present invention is widely used in high-efficiency computer systems of several national supercomputing centers and several data centers. According to the actual test results, the PWM duty cycle-speed curve is obtained. When the duty cycle is 100%, the fan runs at full speed (6000RPM). When the duty cycle is 0, the fan speed is 1500RPM. When the duty cycle is 50%, the fan speed is 3700RPM. . When the duty cycle is 50% and 0, the fan current is much smaller than that at full speed. The high-efficiency computer system of the supercomputing center uses nearly 10,000 fans, which will save a lot of power. Based on the average energy saving of 10w per fan, the entire system saves more than 2000kwh of electric energy every 24 hours.

2. The high-frequency pulse width modulation control circuit of the present invention, compared with low-frequency PWM, adopts high-frequency (22.5KHz) pulse width modulation to make the fan be switched by the frequency that cannot be heard, while keeping the power line and ground wire of the fan continuous , significantly reducing or even eliminating rectification noise. It has a wider control range than linear control. Using high-frequency pulse width control, the fan can run between 10% and full speed, while the same fan can only run from 50% to full speed using linear control. This is very efficient because the coil power is either fully on or fully off. At the same time, the transistor is either off or saturated, and its loss is very low, which avoids the loss generated by the transistor in the linear control mode. Since the fan runs at a relatively low speed (which can be changed gradually), this is much quieter than full on or frequent on/off operation. Moreover, the low-speed operation of the fan can increase its life and improve system reliability.

3. The design of the hot-swappable circuit enables the 12V air-cooled control module and the fan group of the present invention to be plugged and pulled from the backplane together with electricity, and to realize continuous power replacement and maintenance in the case of failure of the present invention or the fan group. At the same time, when the power is initially turned on, the fan group is powered on for a delay (after the working voltage is stabilized), so as to ensure that there will be no impact on the bus voltage of the backplane.

4. The design of the filter decoupling circuit of the present invention can greatly absorb and eliminate the interference current generated when the fan is working, so as to ensure the stable operation of the high-efficiency computer system during normal operation, and there will be no impact on the bus voltage due to the operating current of the fan group. interference and affect the system operation.

5. The backplane connector of the present invention realizes the reliable connection between the 12V air-cooled control module and the fan group and the backplane of the high-performance computer system, completes the transmission of monitoring signals and electric energy, and satisfies relatively convenient plugging and unplugging operations.

Description of drawings

Fig. 1 is the overall structure of the present invention and the present invention is installed in the high-performance computer system cabinet and the connection schematic diagram of external parts;

Fig. 2 is a logic structure diagram of the hot swap circuit of the present invention;

Fig. 3 is a logic structure diagram of the filter decoupling circuit of the present invention;

Fig. 4 is a logic structure diagram of the high frequency pulse width modulation control circuit of the present invention.

Detailed ways

As shown in FIG. 1 , the 12V DC air-cooled control module of the present invention is installed in a subframe providing cooling service in a high-performance computer system cabinet, and is connected with the backplane of the computer. The invention is composed of a backplane connector, a hot plug circuit, a filter decoupling circuit, a high-frequency pulse width modulation (PWM) control circuit, and a fan connector, all of which are integrated on one printed circuit board. The present invention is connected with the system backplane through the backplane connector, and the present invention is connected with the fan group through the fan connector.

The backplane connector adopts a commercial connector (such as FCI's product number 51700), which requires a load current capacity of no less than 20A and no less than 6 signal pins. The backplane connector is connected with the backplane of the computer system, the internal hot-swap controller of the present invention, and the high-frequency pulse width modulation control circuit, and provides 12V DC power supply, 3.3V DC power supply, ground, signal, etc. for other components of the present invention Electrical transmission and connection; the backplane connector provides a channel for the system monitoring unit (monitor and control unit, MCU) to monitor and control the fan group connected to the present invention.

The hot-swapping circuit is connected with the backplane connector and the filter decoupling circuit to provide the present invention with functions of overcurrent protection, overvoltage protection, undervoltage protection, power-on slow start, and live plugging and unplugging, eliminating the need for 12V DC air-cooled control modules to The impact and interference on the bus voltage during electric starting and hot plugging. As shown in Figure 2, the hot-swap circuit is composed of a filter, a first voltage divider, a current-sensing resistor, a hot-swap controller, a timer, a second voltage divider and a switch tube. The filter is connected to the backplane connector, the first voltage divider, and the current-sensing resistor. It is composed of a conventional RC filter circuit connected in parallel with the first diode. The RC filter circuit uses a 10Ω resistor and a 0.1μf/25V Capacitors are connected in series, the resistance of the RC circuit and the first diode are connected to the backplane connector, the first voltage divider, and the current detection resistor, and the other ends of the first diode and the capacitor of the RC circuit are connected to the ground. Both the first voltage divider and the second voltage divider are composed of the first voltage divider resistor and the second voltage divider resistor connected in series, which meet the current limit of less than 10μA and realize the start-up threshold design of 10.8V at the same time. During design, the optional first voltage dividing resistor is 60.4kΩ, and the second voltage dividing resistor is 8.45kΩ. The first voltage divider is externally connected to the backplane connector, and internally connected to the hot-swap controller, filter, and current-sensing resistor. The first voltage dividing resistor of the first voltage divider is connected with the backplane connector, the current detection resistor and the filter, and the second voltage dividing resistor is connected with the hot swap controller. The second voltage divider is connected with the hot-swappable controller, the switch tube, and the filter decoupling circuit; the first voltage divider resistor of the second voltage divider is connected with the switch tube and the filter decoupling circuit; The voltage divider resistor is connected to the hot-swap controller. The current-sensing resistor is a 0.002Ω/3W resistor, which is externally connected to the backplane connector and internally connected to the switch tube, hot-swap controller, filter, and the first voltage divider. The hot-swap controller is connected with the first voltage divider, current-sensing resistor, switch tube, second voltage divider, and timer. It adopts a commercial hot-swap controller with an operating voltage of ≥12V and an operating temperature of 0-70°C. , With current detection function, it also has over-current protection, over-voltage protection, under-voltage protection, and timing start function. The timer is connected to the hot-swap controller and consists of a 1nf/50V first capacitor and a 22nf/50V second capacitor. One end of the two capacitors is connected to the hot-swap controller, and the other end is grounded. One capacitor is used to set the fault protection time, and the second capacitor is used to set the startup time. The switch tube is connected with the current-sensing resistor, the hot-swap controller, the second voltage divider and the filter decoupling circuit, and adopts N-MOS with a working voltage of 30V, a working current ≥ 50A, and a conduction resistance R _DS ≤ 0.01Ω.

The filter decoupling circuit is connected with the hot-swap circuit and the fan connector, as shown in Figure 3, it is composed of a two-stage LC filter circuit, the first stage is a public filter, and the switch tube of the hot-swap circuit, the second voltage divider The device is connected with the first split filter, ... the L split filter, ... the N split filter; the second stage is composed of the first split filter, ... the L split filter, ... The Nth shunt filter is composed of the public filter and the fan connector respectively. N is the number of fans in a single fan subrack, which depends on the cooling design and structural design of the computer system. At present, it is generally less than or equal to 6, N≥L≥ 1. The public filter uses a traditional LC filter circuit. The LC filter circuit of the public filter requires an inductance > 500nH, a rated current > 20A, a capacitor capacity > 2.8mf, and a withstand voltage > 16V. The N shunt filters are all composed of a traditional LC filter circuit connected in parallel with a diode. The inductance used in the LC filter circuit in each shunt filter is required to meet the inductance > 10μH, rated current > 4A, and the capacitor used requires a total capacity. > 2.3mf, withstand voltage > 16V, the second diode used requires a withstand voltage of 75V and a forward conduction current of 0.2A. The filter decoupling circuit greatly weakens the interference of the working current of the fan on the 12V bus voltage of the backplane.

The high-frequency pulse width modulation control circuit is connected to the backplane connector and the fan connector, as shown in Figure 4, and consists of a pulse width modulation controller (PWM controller) and a signal level preset circuit. The PWM controller is connected with the signal level preset circuit, the backplane connector and the fan connector, and the signal level preset circuit is connected with the PWM controller and the backplane connector. The PWM controller is a commercial controller with a communication bus, no less than N channels of PWM output, N channels of TACH input channels, and a single address line. The output PWM signal frequency can work at >20KHz and can be set by the user. The PWM signal and the TACH signal of the PWM controller are respectively connected to the PWM signal lines and the TACH signal lines of the N fans through the fan connector. The SCL pin, SDA pin, FSPEED pin and ALERT pin of the PWM controller are connected to the backplane connector to realize communication with the system MCU. The PWM controller accepts the read/write operation commands sent by the system MCU according to the temperature collection in the system, the statistics of the workload of the system and the results of the system idle state query through the backplane connector, so as to adjust the wind speed of the fan; at the same time Report the status and speed information of the fan to the system MCU through the communication bus through the backplane connector. The PWM controller accepts the MCU's write operation to its configuration register through the backplane connector, and sets the pulse width modulation frequency to 22.5KHz. The VCC pin and GND pin of the PWM controller are connected to the backplane through the backplane connector to obtain power. The signal level preset circuit is composed of 2N+4 resistors connected in parallel. Among them, one end of the two 2.2kΩ resistors is connected to the PWM controller, and the other end is connected to the backplane connector to realize the preset values of the clock signal SCL and the data signal SDA. One end of two 10kΩ resistors is connected to the PWM controller, and the other end is connected to the backplane connector to realize the preset value of the interrupt/alarm signal ALERT and the wind speed setting signal FSPEED. One end of 2N 2.2kΩ resistors is connected to the fan connector, and the other end is connected to the backplane connector to realize the preset values of N PWM signals and N TACH signals.

The fan connector is connected with the filter decoupling circuit, the high-frequency pulse width modulation control circuit, and the fan group, and is composed of N 4-core commercial connectors connected in parallel. The fan connector requires the load capacity of each pin to be >5A.

Claims (7)

1. A 12V DC air-cooled control module is characterized in that the 12V DC air-cooled control module is installed in the high-performance computer system cabinet to provide cooling service in the subframe, connected with the backboard of the computer, by the backplane connector, heat Plug-in circuit, filter decoupling circuit, high-frequency pulse width modulation control circuit, fan connector; The backplane connector adopts a commercial connector, and the load current capacity is required to be not less than 20A, and the signal pins are not less than 6. The backplane connector is compatible with the backplane of the computer system, the hot-swappable controller, and the high-frequency pulse width modulation control circuit. Connected to provide 12V DC power supply, 3.3V DC power supply, ground, and signal transmission and connection for other components of the 12V DC air-cooled control module; The hot-swap circuit is connected with the backplane connector and the filter decoupling circuit. The hot-swap circuit is composed of a filter, a first voltage divider, a current-sensing resistor, a hot-swap controller, a timer, a second voltage divider and a switch The filter is connected with the backplane connector, the first voltage divider, and the current-sensing resistor, and is formed by connecting the RC filter circuit and the first diode in parallel. The board connector, the first voltage divider, and the current detection resistor are connected, and the other end of the capacitor of the first diode and the RC filter circuit is connected to the ground; the voltage divider and the second voltage divider are both composed of the first voltage divider resistor and The second voltage divider is connected in series to meet the current limit of less than 10μA, and at the same time realize the startup threshold design of 10.8V; the first voltage divider is externally connected to the backplane connector, and internally connected to the hot swap controller, filter, detector The first voltage dividing resistor of the first voltage divider is connected with the backplane connector, the current detection resistor, and the filter, and the second voltage dividing resistor of the first voltage divider is connected with the hot-swap controller; the second The voltage divider is connected with the hot-swappable controller, the switch tube, and the filter decoupling circuit; the first voltage divider resistor of the second voltage divider is connected with the switch tube and the filter decoupling circuit; The resistor is connected to the hot-swap controller; the current-sensing resistor is a 0.002Ω/3W resistor, which is externally connected to the backplane connector, and internally connected to the switch tube, hot-swap controller, filter, and the first voltage divider; The hot-swap controller is connected with the first voltage divider, current-sensing resistor, switch tube, second voltage divider, and timer. It adopts a working voltage ≥ 12V and a working temperature of 0-70°C. It has the function of current detection and Commercial hot-swap controller with over-current protection, over-voltage protection, under-voltage protection, and timing start functions; the timer is connected to the hot-swap controller; the switch tube is connected to the current-sensing resistor, the hot-swap controller, and the second voltage divider Connected to the filter and decoupling circuit, using N-MOS with a working voltage of 30V, a working current ≥ 50A, and a conduction resistance R _DS ≤ 0.01Ω; The filter decoupling circuit is connected with the hot-swappable circuit and the fan connector, and is composed of two-stage LC filter circuits. The filter is connected; the second stage is composed of N shunt filters, which are respectively connected to the public filter and the fan connector; the public filter uses an LC filter circuit, and the N shunt filters are connected in parallel by an LC filter circuit and a diode N is the number of fans in a single fan subrack, N≥1; The high-frequency pulse width modulation control circuit is connected with the backplane connector and the fan connector, and is composed of a pulse width modulation controller (PWM controller) and a signal level preset circuit; the PWM controller and signal level preset circuit, the backplane The connector and the fan connector are connected, and the signal level preset circuit is connected with the PWM controller and the backplane connector; the PWM controller is selected to have a communication bus, no less than N channels of PWM output and N channels of TACH input channels, and a single address line of commercial controllers, the output PWM signal frequency can work at >20KHz, and can be set by the user; the PWM signal and TACH signal of the PWM controller are respectively connected to the PWM signal line and TACH signal line of N fans through the fan connector Connection, the SCL pin, SDA pin, FSPEED pin and ALERT pin of the PWM controller are connected to the backplane connector to realize communication with the system MCU; the PWM controller accepts the system MCU through the backplane connector according to the temperature in the system The read/write operation commands sent by collecting and counting the workload of the system and the results of the system idle status query, so as to adjust the fan speed; at the same time, report the fan status to the system MCU through the backplane connector through the communication bus Status and speed information; the PWM controller accepts the MCU’s write operation to its configuration register through the backplane connector, and sets the pulse width modulation frequency to 22.5KHz; the VCC pin and GND pin of the PWM controller communicate with the MCU through the backplane connector The backplane is connected to obtain power; the signal level preset circuit is composed of 2N+4 resistors connected in parallel; among them, one end of two 2.2kΩ resistors is connected to the PWM controller, and the other end is connected to the backplane connector to realize the clock signal SCL , the preset value of the data signal SDA; one end of two 10kΩ resistors is connected to the PWM controller, and the other end is connected to the backplane connector to realize the preset value of the interrupt/alarm signal ALERT and the wind speed setting signal FSPEED; 2N 2.2kΩ One end of the resistor is connected to the fan connector, and the other end is connected to the backplane connector to realize the preset values of N PWM signals and N TACH signals; The fan connector is connected with the filter decoupling circuit, high-frequency pulse width modulation control circuit, and fan group. It is composed of N 4-core commercial connectors connected in parallel. The fan connector requires a load capacity of each pin > 5A. 2. A 12V DC air-cooled control module as claimed in claim 1, characterized in that said backplane connector, hot-swappable circuit, filter decoupling circuit, high-frequency pulse width modulation (PWM) control circuit, fan connection The devices are all integrated on one printed circuit board. 3. A 12V DC air-cooled control module as claimed in claim 1, characterized in that the RC filter circuit of the filter in the hot-swappable circuit consists of a 10Ω resistor connected in series with a 0.1μf/25V capacitor . 4. A 12V DC air-cooled control module as claimed in claim 1, wherein the timer is composed of a first capacitor of 1nf/50V and a second capacitor of 22nf/50V, one end of the two capacitors Both are connected to the hot-swap controller, and the other end is grounded. 5. A 12V DC air-cooled control module as claimed in claim 1, characterized in that the LC filter circuit of the public filter requires an inductance>500nH, a rated current>20A, and requires a capacitor capacity>2.8mf, voltage>16V; the inductance used in the LC filter circuit in the N shunt filters is required to meet the requirements of inductance>10μH, rated current>4A, the capacitor used requires a total capacity>2.3mf, and a withstand voltage>16V. The pole tube requires a withstand voltage of 75V and a forward conduction current of 0.2A. 6. A 12V DC air-cooled control module as claimed in claim 1, characterized in that the PWM controller accepts the write operation of the MCU to its configuration register through the backplane connector, and sets the pulse width modulation frequency to 22.5KHz . 7. A 12V DC air-cooled control module as claimed in claim 1, characterized in that the first divider resistance of the first divider and the second divider is 60.4kΩ, and the second divider resistance is 8.45 kΩ.

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