Multiple power supply device

This application claims the priority benefit of China application Ser. No. 201010556487.3, filed on Nov. 18, 2010. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

1. Field of the Invention

The present invention generally relates to a power supply device, in particular, to a multiple power supply device.

2. Description of Related Art

A programmable chip is widely used in server system designs as it can be flexibly adjusted by programming, and the programmable chip includes, for example, a complex programmable logic device (CPLD) and a field programmable gate array (FPGA). In conventional designs, the power supply to the programmable chip is steady and unique. However, with the ever increasing of system complexity, the programmable chip may have a plurality of power supplies, and needs to select one from the plurality of power supplies and switch to the selected power supply.

Accordingly, the present invention is directed to a multiple power supply device, which can automatically select a working voltage output by a plurality of power supply units.

The present invention provides a multiple power supply device, which includes a power consuming unit, a plurality of power supply units, and a plurality of switching units. The power consuming unit has a power receiving terminal and a plurality of detection terminals. The detection terminals receive a plurality of power good signals respectively, and the power consuming unit outputs a plurality of power control signals according to the power good signals. The power supply units are used to output a plurality of working voltages respectively, and output the power good signals correspondingly when outputting the working voltages. The switching units are coupled to the power receiving terminal, and are coupled to the power supply units respectively. When the power consuming unit is in a working state and one of the power good signals is enabled, the power consuming unit enables the corresponding power control signal, and the switching units transmit the corresponding working voltage to the power receiving terminal according to the enabled power control signal. When the power consuming unit is in a working state and a part of the power good signals are enabled, the power consuming unit enables one of the power control signals corresponding to the enabled power good signals, and the switching units transmit the corresponding working voltage to the power receiving terminal according to the enabled power control signal.

In an embodiment of the present invention, when the power consuming unit is not started and one of the power supply units outputs the working voltage, the switching unit that receives the working voltage outputs a starting voltage to the power receiving terminal. When the power consuming unit is not started and a part of the power supply units output the working voltages, one of the switching units that receive the working voltages outputs the starting voltage to the power receiving terminal.

In an embodiment of the present invention, the switching units include switches and diodes. A first terminal of the switch is coupled to a corresponding power supply unit, a second terminal of the switch is coupled to the power receiving terminal of the power consuming unit, and a control terminal of the switch receives the corresponding power control signal. The diode is forward coupled between the first terminal and the second terminal of the switch. When the power consuming unit is not started and one of the power supply units outputs the working voltage, the corresponding diode in the switching units is forward conducted, outputs a starting voltage according to the working voltage, and transmits the starting voltage to the power receiving terminal of the power consuming unit, so that the power consuming unit is actuated and starts working. When the power consuming unit is not started and a part of the power supply units output the working voltages, the diode that receives the working voltage first among the diodes in the switching units is forward conducted, outputs the starting voltage according to the received working voltage, and transmits the starting voltage to the power receiving terminal of the power consuming unit, so that the power consuming unit is actuated and starts working. When the power consuming unit is in a working state and one of the power good signals is enabled, the corresponding power control signal is enabled to conduct the corresponding switch in the switching units, and the working voltage is transmitted to the power receiving terminal of the power consuming unit through the conducted switch. When the power consuming unit is in a working state and a part of the power good signals are enabled, one of the power control signals is enabled correspondingly to conduct the corresponding switch in the switching units, and the working voltage is provided to the power receiving terminal of the power consuming unit through the conducted switch.

In an embodiment of the present invention, when the power consuming unit is not started, all of the power good signals are disabled, and all of the switches are turned off.

In an embodiment of the present invention, when one of the diodes is forward conducted, the other diodes are all cut off.

In an embodiment of the present invention, the starting voltage is lower than the working voltage.

In an embodiment of the present invention, the switches are P-channel metal-oxide-semiconductor (PMOS) transistors.

In an embodiment of the present invention, the power supply units are a plurality of power supply.

In an embodiment of the present invention, the power supply units are a plurality of power converters.

In an embodiment of the present invention, the power consuming unit is a programmable chip, and the power consuming unit is a CPLD or an FPGA.

In view of the above, in the multiple power supply device of the present invention, the power consuming unit automatically selects the working voltage output by one of the power supply units according to the power good signal. Before the power consuming unit is started, one of the switching units generates a starting voltage according to the working voltage output by the power supply units, and transmits the starting voltage to the power consuming unit.

In order to make the aforementioned features and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below.

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

FIG. 1 is a system schematic view of a multiple power supply device according to an embodiment of the present invention.

FIG. 2 is a schematic circuit diagram of a multiple power supply device according to an embodiment of the present invention.

Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.

Currently, with the ever increasing of system complexity, a programmable chip may be shared by a plurality of main boards, so that the programmable chip may be required to select one voltage from a plurality of voltages and switch a working voltage to the selected one. In a system having multiple main boards, when an expansion card with a programmable chip is shared by the main boards, since one or more of the main boards can be switched on and the main boards to be switched on are not fixed, the design of a circuit applying the programmable chip has the following requirements. When any one of the main boards is in a working state, the programmable chip uses a voltage of the working main board as the working voltage; and when multiple main boards are in a working state simultaneously, the programmable chip uses a voltage corresponding to one of the working main boards as the working voltage.

FIG. 1 is a system schematic view of a multiple power supply device according to an embodiment of the present invention. Referring to FIG. 1 , the multiple power supply device 100 includes a power consuming unit 110 , a plurality of power supply units (e.g. 120 _ 1 , 120 _ 2 , . . . ), and a plurality of switching units (e.g. 130 _ 1 , 130 _ 2 , . . . ). The power consuming unit 110 may be a programmable chip, and may also be a CPLD or an FPGA. The power supply units 120 _ 1 , 120 _ 2 , . . . output voltages (e.g. V 1 , V 2 , . . . ), and output power good signals (e.g. PGD 1 , PGD 2 , . . . ) when outputting the voltages, in which the voltages V 1 , V 2 , . . . are substantially the same.

The power consuming unit 110 has a power receiving terminal PWD, a plurality of detection terminals (e.g. PD 1 , PD 2 , . . . ), and a plurality of output terminals (e.g. O 1 , O 2 , . . . ). The power receiving terminal PWD is used to receive a working voltage VCC to actuate the power consuming unit 110 to work. The detection terminals PD 1 , PD 2 , . . . receive the power good signals PGD 1 , PGD 2 , . . . respectively. The power consuming unit 110 outputs a plurality of power control signals (e.g. PCL 1 , PCL 2 , . . . ) at the output terminals O 1 , O 2 , . . . according to the power good signals PGD 1 , PGD 2 , . . . respectively. The switching units 130 _ 1 , 130 _ 2 , . . . are coupled to the power consuming unit 110 , and are coupled to the power supply units 120 _ 1 , 120 _ 2 , . . . respectively.

When the power consuming unit 110 is in a working state, and one of the power good signals PGD 1 , PGD 2 , . . . is enabled, the power consuming unit 110 enables the corresponding power control signal (e.g. PCL 1 , PCL 2 , . . . ). The switching units 130 _ 1 , 130 _ 2 , . . . transmit a corresponding voltage (e.g. V 1 , V 2 , . . . ) to the power consuming unit 110 according to the enabled power control signal (e.g. PCL 1 , PCL 2 , . . . ), and the corresponding voltage is used as the working voltage VCC of the power consuming unit 110 . The working voltage VCC is substantially equal to the voltage V 1 or V 2 . When the power consuming unit 110 is in a working state, and a part of the power good signals PGD 1 , PGD 2 , . . . are enabled, the power consuming unit 110 enables one of the power control signals (e.g. PCL 1 , PCL 2 , . . . ) corresponding to the enabled power good signals (e.g. PGD 1 , PGD 2 , . . . ). The switching units 130 _ 1 , 130 _ 2 , . . . transmits a corresponding voltage (e.g. V 1 , V 2 , . . . ) to the power consuming unit 110 according to the enabled power control signal (e.g. PCL 1 , PCL 2 , . . . ), and the corresponding voltage is used as the working voltage VCC of the power consuming unit 110 .

For example, when the power consuming unit 110 is in a working state and the power supply unit 120 _ 1 outputs the voltage V 1 , the power good signal PGD 1 is enabled. In this case, the power consuming unit 110 enables the power control signal PCL 1 , and the switching unit 130 _ 1 transmits the voltage V 1 to the power receiving terminal PWD of the power consuming unit 110 according to the enabled power control signal PCL 1 , in which the voltage V 1 is used as the working voltage VCC of the power consuming unit 110 . When the power consuming unit 110 is in a working state and the power supply units 120 _ 1 and 120 _ 2 output the voltages V 1 and V 2 respectively, the power good signals PGD 1 and PGD 2 are enabled. In this case, the power consuming unit 110 enables one of the power control signals PCL 1 and PCL 2 , and one of the switching units 130 _ 1 and 130 _ 2 transmits the voltage (e.g. V 1 or V 2 ) to the power receiving terminal PWD of the power consuming unit 110 according to the enabled power control signal (e.g. PCL 1 or PCL 2 ), in which the voltage (e.g. V 1 or V 2 ) is used as the working voltage VCC of the power consuming unit 110 .

In addition, when the power consuming unit 110 is not started and one of the power supply units 120 _ 1 , 120 _ 2 , . . . outputs a voltage (e.g. V 1 , V 2 , . . . ), the switching unit (e.g. 130 _ 1 , 130 _ 2 , . . . ) that receives the voltage (e.g. V 1 , V 2 , . . . ) outputs a starting voltage VST according to the received voltage (e.g. V 1 , V 2 , . . . ), and transmits the starting voltage VST to the power consuming unit 110 , so as to actuate the power consuming unit 110 . When the power consuming unit 110 is not started and a part of the power supply units 120 _ 1 , 120 _ 2 , . . . output voltages (e.g. V 1 , V 2 , . . . ), one of the switching units (e.g. 130 _ 1 , 130 _ 2 , . . . ) that receive the voltages (e.g. V 1 , V 2 , . . . ) outputs a starting voltage VST according to the received voltage (e.g. V 1 , V 2 , . . . ), and transmits the starting voltage VST to the power consuming unit 110 , so as to actuate the power consuming unit 110 . In particular, the starting voltage VST is lower than the working voltage VCC.

For example, when the power consuming unit 110 is not started and the power supply unit 120 _ 1 outputs a voltage V 1 , the switching unit 130 _ 1 outputs a starting voltage VST according to the voltage V 1 , and transmits the starting voltage VST to the power receiving terminal PWD of the power consuming unit 110 , so as to actuate the power consuming unit 110 . When the power consuming unit 110 is not started and the power supply units 120 _ 1 and 120 _ 2 output voltages V 1 and V 2 respectively, one of the switching units 130 _ 1 and 130 _ 2 outputs a starting voltage VST according to a voltage (e.g. V 1 or V 2 ), and transmits the starting voltage VST to the power receiving terminal PWD of the power consuming unit 110 , so as to actuate the power consuming unit 110 . The other one of the switching units 130 _ 1 and 130 _ 2 does not perform any action.

FIG. 2 is a schematic circuit diagram of a multiple power supply device according to an embodiment of the present invention. Referring to FIG. 1 and FIG. 2 , in this embodiment, the power supply units 120 _ 1 , 120 _ 2 , . . . may be, for example, power supply 120 _ 1 , 120 _ 2 , . . . , while in other embodiments, the power supply units may be power converters. Additionally, the switching unit 130 _ 1 includes a transistor M 1 and a diode D 1 , the switching unit 130 _ 2 includes a transistor M 2 and a diode D 2 , and the structures of the other switching units are the same as those of the switching units 130 _ 1 and 130 _ 2 , the details of which will not be described herein again. The transistors M 1 and M 2 may be, for example, PMOS transistors, and each of the transistors may be regarded as a switch.

A source (that is, a first terminal) of the transistor M 1 is coupled to the power supply 120 _ 1 to receive a voltage V 1 , a drain (that is, a second terminal) of the transistor M 1 is coupled to the power receiving terminal PWD of the power consuming unit 110 to output a working voltage VCC to the power receiving terminal PWD of the power consuming unit 110 , and a gate (that is, a control terminal) of the transistor M 1 receives a power control signal PCL 1 . The diode D 1 is forward coupled between the drain and the source of the transistor M 1 . That is to say, an anode of the diode D 1 is coupled to the source of the transistor M 1 , and a cathode of the diode D 1 is coupled to the drain of the transistor M 1 .

A source of the transistor M 2 is coupled to the power supply 120 _ 2 to receive a voltage V 2 , a drain of the transistor M 2 is coupled to the power receiving terminal PWD of the power consuming unit 110 to output a working voltage VCC to the power receiving terminal PWD of the power consuming unit 110 , and a gate of the transistor M 2 receives a power control signal PCL 2 . The diode D 2 is forward coupled between the drain and the source of the transistor M 2 . That is to say, an anode of the diode D 2 is coupled to the source of the transistor M 2 , and a cathode of the diode D 2 is coupled to the drain of the transistor M 2 . The rest can be deduced in the same manner, and will not be described herein again.

When none of the power supply apparatuses 120 _ 1 , 120 _ 2 , . . . are switched on, none of the main boards are switched on. In this case, the power supply apparatuses 120 _ 1 , 120 _ 2 , . . . cannot supply voltages V 1 , V 2 , . . . , the power good signals PGD 1 , PGD 2 , . . . are disabled (for example, at a low voltage level), the transistors M 1 , M 2 , . . . are not conducted (equivalent to turn-off of the switches), and the diodes D 1 , D 2 , . . . are cut off. Since the voltages V 1 , V 2 , . . . cannot be transmitted to the power receiving terminal PWD of the power consuming unit 110 to serve as the working voltage VCC, and the diodes D 1 , D 2 , . . . cannot generate a starting voltage VST according to the voltages V 1 , V 2 , . . . , the power consuming unit 110 is not actuated.

When one of the power supply apparatuses 120 _ 1 , 1202 , . . . is switched on, a corresponding main board is switched on. Assuming that the power supply switched on is the power supply 120 _ 1 , the power supply 120 _ 1 provides the voltage V 1 , and the power good signal PGD 1 is enabled (for example, at a high voltage level). In this case, the diode D 1 receives a forward bias to be forward conducted, lowers the voltage V 1 by a threshold voltage, and transmits the lowered voltage to the power receiving terminal PWD of the power consuming unit 110 , in which the lowered voltage is used as a starting voltage VST. That is to say, the diode D 1 outputs the starting voltage VST according to the voltage V 1 , and the starting voltage VST is lower than the voltage V 1 .

Before the power receiving terminal PWD of the power consuming unit 110 receives the starting voltage VST or the working voltage VCC, the power consuming unit 110 is in a not started state, so that the output terminals O 1 , O 2 , . . . are in a floating state. Since the gates of the transistors M 1 , M 2 , . . . do not receive any voltage, the transistors M 1 , M 2 , . . . are not conducted (equivalent to turn-off of the switches).

After the power receiving terminal PWD of the power consuming unit 110 receives the starting voltage VST, the power consuming unit 110 is in a working state. Since the power good signal PGD 1 is enabled, the power consuming unit 110 enables the power control signal PCL 1 . That is to say, the power control signal PCL 1 is switched from a high voltage level to a low voltage level. In this case, the voltage of the gate of the transistor M 1 is far lower than the voltage of the source of the transistor M 1 , so that the transistor M 1 is conducted, and transmits the voltage V 1 to the power receiving terminal PWD of the power consuming unit 110 , in which the voltage V 1 is used as the working voltage VCC. The working voltage VCC is substantially equal to the voltage V 1 . In addition, since the working voltage VCC is substantially equal to the voltage V 1 , the diode D 1 may be cut off due to the inadequate forward bias.

Moreover, when more than two of the power supply apparatuses 120 _ 1 , 120 _ 2 , . . . are switched on, the corresponding main boards are switched on. Assuming that the power supply apparatuses switched on are the power supply apparatuses 120 _ 1 and 1202 , the power supply 120 _ 1 provides the voltage V 1 , the power supply 120 _ 2 provides the voltage V 2 , and the power good signals PGD 1 and PGD 2 are enabled. In this case, the diodes D 1 and D 2 receive a forward bias. The diode that receives the voltage (e.g. V 1 or V 2 ) first between the diodes D 1 and D 2 is conducted first, and outputs the starting voltage VST to the power receiving terminal PWD of the power consuming unit 110 according to the voltage (e.g. V 1 or V 2 ), and the other diode is cut off instantly. Since the diodes D 1 and D 2 are forward conducted elements, the power supply apparatuses 120 _ 1 and 1202 are prevented from being conducted to each other, thus avoiding reverse or unbalanced power supply. Assuming that the conducted diode is the diode D 2 , the diode D 2 generates the starting voltage VST according to the voltage V 2 , and transmits the starting voltage VST to the power receiving terminal PWD of the power consuming unit 110 .

Before the power receiving terminal PWD of the power consuming unit 110 receives the starting voltage VST and the working voltage VCC, the power consuming unit 110 is in a not started state, so that the output terminals O 1 , O 2 , . . . are in a floating state. Since the gates of the transistors M 1 , M 2 , . . . do not receive any voltage, the transistors M 1 , M 2 , . . . are not conducted. After the power receiving terminal PWD of the power consuming unit 110 receives the starting voltage VST, the power consuming unit 110 is in a working state. Since the power good signals PGD 1 and PGD 2 are enabled, the power consuming unit 110 enables one of the power control signals PCL 1 and PCL 2 . The selection method may be performed in an order or randomly, and can be designed by persons of ordinary skill in the art, so the present invention is not limited thereto. Assuming that the power control signal PCL 2 is enabled, the transistor M 2 is conducted, and transmits the voltage V 2 to the power receiving terminal PWD of the power consuming unit 110 , in which the voltage V 2 is used as the working voltage VCC. The working voltage VCC is substantially equal to the voltage V 2 . In addition, since the working voltage VCC is substantially equal to the voltage V 2 , the diodes D 1 and D 2 may be cut off due to the inadequate forward bias.

In view of the above, in the multiple power supply device according to the embodiments of the present invention, before the power consuming unit works, the diode that receives the voltage first is conducted, and outputs the starting voltage to the power consuming unit to actuate the power consuming unit. When the power consuming unit is in a working state, the power consuming unit may automatically select the received voltage as the working voltage according to the power good signal of the power supply apparatus. In addition, since the diodes are forward conducted elements, the power supply apparatuses are prevented from being conducted to each other, thus avoiding reverse or unbalanced power supply.

It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.