Power control circuit for hard disk drive

• US 8,122,267 B2
• Filed: 08/20/2009
• Issued: 02/21/2012
• Est. Priority Date: 07/20/2009
• Status: Expired due to Fees

• Current Assignee: Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. (Hon Hai Precision Industry Co., Ltd.), Hon Hai Precision Industry Co., Ltd.
• Original Assignee: Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. (Hon Hai Precision Industry Co., Ltd.), Hon Hai Precision Industry Co., Ltd.
• Inventors: Rui, Yi, Shen, Jian-She, Li, Cheng-Yang
• Primary Examiner(s): Benson, Walter
• Assistant Examiner(s): Carrasquillo, Jorge
• Application Number:
  US12/545,032
• Publication Number:
  US 20110012546A1
• Time in Patent Office: 915 Days
• Field of Search: 318/400.3, 714/26, 714/36, 714/55, 714/11.002, 714/11.145, 713/300, 324/555, 717/173, 717/100, 323/304
• US Class Current: 713/300
• CPC Class Codes: G06F 1/266 Arrangements to supply power to external peripherals either directly from the computer or under computer control, e.g. supply of power through the communication port, computer controlled power-strips

Abstract

A power control circuit for a hard disk drive (HDD) includes a first control circuit, a second control circuit, a first connector connected to a power supply, the first and second control circuits, and a second connector connected to the first control circuit and the HDD. The power supply outputs a first voltage signal and a second voltage signal to the first and second control circuits via the first connector. The first control circuit converts the first and second voltage signals into a form compatible with a timing sequence of the HDD receiving voltage signals, and outputs the first and second voltage signals to the HDD via the second connector. The second control circuit controls the first control circuit.

Claims

1. A power control circuit for a hard disk drive (HDD), the circuit comprising:

a first connector connected to a power supply, comprising a first power input pin receiving a first voltage signal from the power supply, and a second power input pin receiving a second voltage signal from the power supply;

a second connector connected to the HDD, the second connector comprising a detection pin outputting a detection signal, a first power output pin outputting the first voltage signal to the HDD, and a second power output pin outputting the second voltage signal to the HDD; and

a first control circuit, comprising;

a first electric switch comprising a control terminal connected to the detection pin of the second connector receiving the detection signal and connected to the second power input pin of the first connector via a first resistor, a power terminal connected to the second power input pin of the first connector via a second resistor, and a ground terminal;

a second electric switch comprising a control terminal connected to the power terminal of the first electric switch, a power terminal connected to the first power input pin of the first connector via a third resistor, and a ground terminal;

a third electric switch comprising a control terminal connected to the power terminal of the second electric switch, an input terminal connected to the first power input pin of the first connector, and an output terminal connected to the first power output pin of the second connector; and

a fourth electric switch comprising a control terminal connected to the output terminal of the third electric switch via a fourth resistor, an input terminal connected to the second power input pin of the first connector, and an output terminal connected to the second power output pin of the second connector;

wherein in response to the HDD being properly connected to the second connector, the detection pin outputs the detection signal at a low level to turn off the first electric switch, therefore, the second, third, and fourth electric switches are turned on, the first and second voltage signals are transmitted to the HDD via the third and fourth electric switches and the second connector.

2. The circuit of claim 1, wherein the first, second, third, and fourth electric switches are metal-oxide-semiconductor field-effect transistors (MOSFETs).

3. The circuit of claim 2, wherein the first and second electric switches are N-channel MOSFETs, the control, power, and ground terminals of each of the first and second electric switches are a gate, a drain, and a source, respectively.

4. The circuit of claim 2, wherein the third electric switch is a P-channel MOSFET, and the control, input, and output terminals of the third electric switch are a gate, a source, and a drain, respectively.

5. The circuit of claim 2, wherein the fourth electric switch is an N-channel MOSFET, and the control, input, and output terminals of the fourth electric switch are a gate, a drain, and a source, respectively.

6. The circuit of claim 1, wherein each of the first and second power input pins of the first connector, and the first and second power output pins of the second connector is grounded via a filtering circuit.

7. The circuit of claim 6, wherein each filtering circuit includes a first capacitor and a second capacitor connected in parallel.

8. The circuit of claim 7, wherein the first capacitor is an electrolytic capacitor to filter noise signals of low frequency.

9. The circuit of claim 7, wherein the second capacitor is a ceramic capacitor to filter noise signals of high frequency.

10. A power control circuit for a hard disk drive (HDD), the circuit comprising:

a first connector connected to a power supply, the first connector comprising a first power input pin receiving a first voltage signal from the power supply, and a second power input pin receiving a second voltage signal from the power supply;

a second connector connected to the HDD, the second connector comprising a detection pin outputting a detection signal, a first power output pin outputting the first voltage signal, and a second power output pin outputting the second voltage signal;

a first control circuit, comprising;

a first electric switch comprising a control terminal connected to the detection pin of the second connector receiving the detection signal and connected to the second power input pin of the first connector via a first resistor, a power terminal connected to the second power input pin of the first connector via a second resistor, and a ground terminal;

a second electric switch comprising a control terminal connected to the power terminal of the first electric switch, a power terminal connected to the first power input pin of the first connector via a third resistor, and a ground terminal;

a third electric switch comprising a control terminal connected to the power terminal of the second electric switch, an input terminal connected to the first power input pin of the first connector, and an output terminal connected to the first power output pin of the second connector; and

a fourth electric switch comprising a control terminal connected to the output terminal of the third electric switch via a fourth resistor, an input terminal connected to the second power input pin of the first connector, and an output terminal connected to the second power output pin of the second connector; and

a second control circuit, comprising;

a manual switch;

a fifth electric switch comprising a control terminal connected to the second power input pin of the first connector via a fifth resistor and grounded via the manual switch, a power terminal connected to the second power input pin of the first connector via a sixth resistor, and a ground terminal;

a sixth electric switch comprising a control terminal connected to the power terminal of the fifth electric switch, a power terminal connected to the second power input pin of the first connector via a seventh resistor, and a ground terminal;

a seventh electric switch comprising a control terminal connected to the power terminal of the sixth electric switch, a power terminal connected to the control terminal of the second electric switch of the first control circuit, and a ground terminal; and

an eighth electric switch comprising a control terminal connected to the output terminal of the fourth electric switch of the first control circuit via an eighth resistor, a power terminal connected to the power terminal of the sixth electric switch, and a ground terminal;

wherein in response to the manual switch opening, the fifth electric switch is turned on, the sixth electric switch is turned off, and the seventh electric switch is turned on, such that the second, third, and fourth electric switches are turned off and the first control circuit cannot output the first and second voltage signals; and

wherein in response to the HDD being effectively connected to the second connector, and the manual switch being closed, the detection pin outputs the detection signal at a low level to turn off the first electric switch, the fifth electric switch is turned off, the sixth electric switch is turned on, and the seventh electric switch is turned off, such that the second, third, and fourth electric switches are turned on, and the first and second voltage signals are transmitted to the HDD via the first control circuit and the second connector, and the second voltage signal is transmitted to the control terminal of the eighth electric switch via the eighth resistor to turn on the eighth electric switch, and the seventh electric switch remains turned off.

11. The circuit of claim 10, wherein the first, second, third, fourth, fifth, sixth, seventh, and eighth electric switches are metal-oxide-semiconductor field-effect transistors (MOSFETs).

12. The circuit of claim 11, wherein the first, second, fifth, sixth, seventh, and eighth electric switches are N-channel MOSFETs, and the control, power, and ground terminals of each of the first, second, fifth, sixth, seventh, and eighth electric switches are a gate, a drain, and a source, respectively.

13. The circuit of claim 11, wherein the fourth electric switch is an N-channel MOSFET, and the control, input, and output terminals of the fourth electric switch are a gate, a drain, and a source, respectively.

14. The circuit of claim 11, wherein the third electric switch is a P-channel MOSFET, and the control, input, and output terminals of the third electric switch are a gate, a source, and a drain, respectively.

15. The circuit of claim 10, wherein each of the first and second power input pins of the first connector, and the first and second power output pins of the second connector is grounded via a filtering circuit.

16. The circuit of claim 15, wherein each filtering circuit includes a first capacitor and a second capacitor connected in parallel.

17. The circuit of claim 16, wherein the first capacitor is an electrolytic capacitor to filter noise signals of low frequency.

18. The circuit of claim 16, wherein the second capacitor is a ceramic capacitor to filter noise signals of high frequency.