Fan control circuit and fan control system

1. A fan control circuit, applied to a server, comprising:

a fan controller connected with at least one fan connector, connected with a baseboard management controller via integrated circuit bus communication lines and outputting a baseboard management controller fan signal, wherein said fan controller is powered by a main power supply; and

a baseboard status detection circuit connected with the baseboard management controller and the fan controller respectively, detecting a heartbeat signal of the baseboard management controller, and controlling an output of a fan pulse signal according to the heartbeat signal so as to control a fan connected with the fan controller to operate normally;

wherein the baseboard status detection circuit comprises:

a heartbeat signal detection circuit connected with an output terminal of the heartbeat signal of the baseboard management controller, detecting the heartbeat signal of the baseboard management controller and outputting a heartbeat status signal; and

a logic control circuit connected with the heartbeat signal detection circuit, and controlling an output of pulse selection signal according to the heartbeat status signal;

wherein the baseboard status detection circuit further comprises:

a pulse generator generating a predetermined fan pulse signal for driving the fan to operate normally; and

a pulse multiplexer connected with the logic control circuit, the pulse generator and the fan controller respectively, wherein the pulse multiplexer chooses to output the predetermined fan pulse signal to an output port of the pulse multiplexer when the pulse selection signal indicates a first selection status, and the pulse multiplexer chooses to output the baseboard management controller fan signal to the output port of the pulse multiplexer when the pulse selection signal indicates a second selection status.

2. The fan control circuit according to claim 1 , wherein the fan connector is electrically connected with the fan controller, and the fan connector detects an operating speed of the fan and outputs the operating speed to the fan controller.

3. A fan control system, comprising a mainboard, a baseboard management controller disposed on the mainboard, a fan control board and the fan control circuit according to claim 2 .

4. The fan control circuit according to claim 1 , wherein the logic control circuit is further connected with the baseboard management controller, and when the integrated circuit bus communication lines carry a failure signal, the baseboard management controller transmits a failure status signal of integrated circuit bus communication to the logic control circuit.

5. A fan control system, comprising a mainboard, a baseboard management controller disposed on the mainboard, a fan control board and the fan control circuit according to claim 4 .

6. The fan control circuit according to claim 1 , further comprising a power supply circuit connected with the fan connector, wherein the power supply circuit comprises:

a backup power supply; and

a control switch connected with the backup power supply, the output port of the pulse multiplexer and the fan connector respectively.

7. The fan control circuit according to claim 6 , wherein the control switch controls the fan connector to have a communication connection with the output port of the pulse multiplexer when the main power supply of the fan controller operates normally, and the control switch controls the fan of the fan connector to run at full speed when the main power supply of the fan controller is interrupted.

8. A fan control system, comprising a mainboard, a baseboard management controller disposed on the mainboard, a fan control board and the fan control circuit according to claim 7 .

9. A fan control system, comprising a mainboard, a baseboard management controller disposed on the mainboard, a fan control board and the fan control circuit according to claim 6 .

10. The fan control circuit according to claim 1 , further comprising:

a first fuse and a second fuse respectively connected with the main power supply;

wherein the first fuse and the second fuse are respectively and correspondingly connected with two rotors of the fan, and respectively provide fused protection to the two rotors.

11. A fan control system, comprising a mainboard, a baseboard management controller disposed on the mainboard, a fan control board and the fan control circuit according to claim 10 .

12. A fan control system, comprising a mainboard, a baseboard management controller disposed on the mainboard, a fan control board and the fan control circuit according to claim 1 .