Computer fan speed control method

• US 5,962,933 A
• Filed: 10/01/1997
• Issued: 10/05/1999
• Est. Priority Date: 05/13/1997
• Status: Expired due to Term

• Current Assignee: Round Rock Research LLC
• Original Assignee: Micro Electronics Incorporated
• Inventors: Amdahl, Carlton G., Smith, Dennis H., Henderson, Michael G.
• Primary Examiner(s): Gaffin, Jeffrey
• Assistant Examiner(s): GARLEPP, EDWIN D
• Application Number:
  US08/942,216
• Time in Patent Office: 734 Days
• Field of Search: 307/116, 307/126, 307/130, 388/827, 388/840, 388/841
• US Class Current: 307/126
• CPC Class Codes: F04D 27/004 by varying driving speed
• CPC Class Codes: G06F 11/0748 in a remote unit communicating with a single-box computer node experiencing an error/fault remote testing G06F11/2294
• CPC Class Codes: G06F 11/0772 Means for error signaling, e.g. using interrupts, exception flags, dedicated error registers
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40
• CPC Class Codes: G06F 11/2294 by remote test
• CPC Class Codes: G06F 11/3055 Monitoring arrangements for monitoring the status of the computing system or of the computing system component, e.g. monitoring if the computing system is on, off, available, not available error or fault processing without redundancy G06F11/0703; error detection or correction by redundancy in data representation G06F11/08; error detection or correction by redundancy in operation G06F11/14; error detection or correction by redundancy in hardware G06F11/16
• CPC Class Codes: G06F 11/3058 Monitoring arrangements for monitoring environmental properties or parameters of the computing system or of the computing system component, e.g. monitoring of power, currents, temperature, humidity, position, vibrations thermal management in cooling arrangements of a computing system G06F1/206
• CPC Class Codes: G06F 11/3089 Monitoring arrangements determined by the means or processing involved in sensing the monitored data, e.g. interfaces, connectors, sensors, probes, agents software debugging using additional hardware using a specific debug interface G06F11/3656; performance evaluation by tracing or monitoring G06F11/3466
• CPC Class Codes: G06F 11/328 Computer systems status display G06F11/327 takes precedence
• CPC Class Codes: G06F 11/3466 Performance evaluation by tracing or monitoring
• CPC Class Codes: G06F 11/3476 Data logging G06F11/14, G06F11/2205 take precedence
• CPC Class Codes: G06F 11/3495 for systems
• CPC Class Codes: G06F 13/4027 using bus bridges G06F13/4022 takes precedence
• CPC Class Codes: G06F 13/4081 Live connection to bus, e.g. hot-plugging current or voltage limitation during live insertion H02H9/004
• CPC Class Codes: G06F 21/305 by remotely controlling device operation
• CPC Class Codes: G06F 21/31 User authentication
• CPC Class Codes: G06F 2201/86 Event-based monitoring
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: G06F 3/0673 Single storage device
• CPC Class Codes: G06F 9/4411 Configuring for operating with peripheral devices; Loading of device drivers
• CPC Class Codes: H02P 7/285 : controlling armature supply only
• CPC Class Codes: H04L 12/12 : Arrangements for remote connection or disconnection of substations or of equipment thereof
• CPC Class Codes: H04L 49/90 : Buffering arrangements
• CPC Class Codes: H04L 67/1001 : for accessing one among a plurality of replicated servers
• CPC Class Codes: H05K 7/20209 : Thermal management, e.g. fan control
• CPC Class Codes: Y02B 30/70 : Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
• CPC Class Codes: Y02D 30/50 : in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A method of cooling computer components is provided. The method comprises positioning the fan adjacent computer components so that the fan is in a position to blow air over the computer components, connecting the fan to a first voltage source through a zener diode voltage divider, connecting the fan to a first voltage source through a switch, manipulating the switch into a first position wherein a first voltage is applied to the fan thereby inducing the fan to operate at a first speed and manipulating the switch into a second position wherein a second voltage is applied to the fan thereby inducing the fan to operate at a second speed which is less than the first speed.

Claims

1. A method of controlling the operation of a fan used to cool computer components, the method comprising:

positioning the fan adjacent computer components so that the fan is in a position to blow air over the computer components;

connecting the fan to a first voltage source through a zener diode voltage divider;

connecting the fan to the first voltage source through a switch;

manipulating the switch into only one of at least two positions at a time;

a first position wherein a first voltage is applied directly to the fan that induces the fan to operate at a first speed, and

a second position wherein a second voltage from the zener diode is applied directly to the fan that induces the fan to operate at a second speed which is less than the first speed, wherein if the fan is receiving the first voltage, the zener diode is shorted.

2. The method of claim 1, wherein the step of connecting the fan to a first voltage source through a voltage divider comprises connecting the fan to the first voltage source through a current independent voltage divider such that the current independent voltage divider reduces the magnitude of the voltage applied to the fan from the first voltage to the second voltage wherein the reduction in magnitude is substantially independent of the current that is drawn by the fan.

3. The method of claim 2, wherein the step of connecting the fan to the first voltage source through a switch comprises connecting the fan to the voltage source through a P-channel MOSFET that is connected in series between the voltage source and the fan so that the switch is connected in parallel to the zener diode voltage divider.

4. The method of claim 2, wherein the step of manipulating the switch into the first position results in the switch shorting out the zener diode so that the fan receives substantially the first voltage provided by the first voltage source.

5. The method of claim 4, wherein the step of manipulating the switch into the second position results in the switch being opened such that the fan receives the second voltage which is equal to the first voltage less the voltage drop provided by the zener diode.

6. The method of claim 5, wherein the first voltage is substantially equal to 12 volts DC and the second voltage is substantially equal to 8.7 volts DC.

7. A method of controlling the operation of a fan used to cool computer components, the method comprising:

positioning the fan adjacent computer components so that the fan is in a position to blow air over the computer components;

connecting the fan to a first voltage source through a zener diode voltage divider so that the voltage received by the fan from the first voltage source is reduced by the zener diode voltage divider and wherein the magnitude of the reduction is substantially independent of the current that is drawn by the fan;

connecting the fan to the first voltage source through a switch;

manipulating the switch into a first position wherein a first voltage is applied to the fan that induces the fan to operate at a first speed; and

manipulating the switch into a second position wherein a second voltage is applied to the fan that induces the fan to operate at a second speed which is less than the first speed, wherein only one of the first and the second voltages is enabled at one time.

8. The method of claim 7, wherein the step of connecting the fan to the first voltage source through a switch comprises connecting the fan to the voltage source through a P-channel MOSFET that is connected in series between the voltage source and the fan so that the switch is connected in parallel to the zener diode voltage divider.

9. The method of claim 7, wherein the step of manipulating the switch into the first position results in the switch shorting out the zener diode so that the fan receives substantially the first voltage provided by the first voltage source.

10. The method of claim 9, wherein the step of manipulating the switch into the second position results in the switch being opened such that the fan receives the second voltage which is equal to the first voltage less the voltage drop provided by the zener diode.

11. The method of claim 10, wherein the first voltage is substantially equal to 12 volts DC and the second voltage is substantially equal to 8.7 volts DC.

12. A method of controlling the operation of a fan used to cool computer components, the method comprising:

positioning the fan adjacent computer components so that the fan is in a position to blow air over the computer components;

connecting the fan to a first voltage source through a zener diode voltage divider;

connecting the fan to the first voltage source through a switch;

manipulating the switch into a first position wherein a first voltage is applied to the fan that induces the fan to operate at a first speed; and

manipulating the switch into a second position wherein a second voltage is applied directly to the fan that induces the fan to operate at a second speed which is less than the first speed, wherein the fan is in electrical contact with only one of the zener diode or the first voltage source at a time.

13. The method of claim 12, wherein the step of connecting the fan to the first voltage source through a switch comprises connecting the fan to the voltage source through a P-channel MOSFET that is connected in series between the voltage source and the fan so that the switch is connected in parallel to the zener diode voltage divider.

14. The method of claim 12, wherein the step of manipulating the switch into the first position results in the switch shorting out the zener diode so that the fan receives substantially the first voltage provided by the first voltage source.

15. The method of claim 14, wherein the step of manipulating the switch into the second position results in the switch being opened such that the fan receives the second voltage which is equal to the first voltage less the voltage drop provided by the zener diode.

16. The method of claim 15, wherein the first voltage is substantially equal to 12 volts DC and the second voltage is substantially equal to 8.7 volts DC.