阅读说明：本技术 防止主机损坏的装置及方法 (Device and method for preventing host machine from being damaged ) 是由 郎维良 李凯 邓忠良 于 2021-07-14 设计创作，主要内容包括：本发明涉及一种防止主机损坏的装置及方法,属于电路保护技术领域,该装置电压比较电路、参考电压电路和电压输出开关；参考电压电路用于产生参考电压；电压比较电路,用于根据参考电压确定参考电压范围,比较输入电压是否在参考电压范围内；若输入电压在参考电压范围内,则触发电压输出开关断开；若输入电压不在参考电压范围内,则触发电压输出开关闭合。本申请通过检测外部电输入是否符合参考电压范围,从而控制外部输入的接入,在外部输入不在参考电压范围内时,断开电压出输出开关,阻断外部输入与主机的连接,从而保护主机不会因输入电压过高或过低而损坏,使得主机在输入电压为正常电压时工作。(The invention relates to a device and a method for preventing a host from being damaged, belonging to the technical field of circuit protection, wherein the device comprises a voltage comparison circuit, a reference voltage circuit and a voltage output switch; the reference voltage circuit is used for generating a reference voltage; the voltage comparison circuit is used for determining a reference voltage range according to the reference voltage and comparing whether the input voltage is in the reference voltage range; if the input voltage is within the reference voltage range, the voltage output switch is triggered to be switched off; and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed. This application is through detecting whether outside electrical input accords with the reference voltage scope to control the access of outside input, when outside input is not in the reference voltage scope, the break-off voltage goes out output switch, blocks being connected of outside input and host computer, thereby the protection host computer can not be because of input voltage is too high or low damage excessively, makes the host computer work when input voltage is normal voltage.)

1. An apparatus for preventing damage to a host, comprising: the voltage comparison circuit, the reference voltage circuit and the voltage output switch; the first input end of the voltage comparison circuit is connected with the reference voltage circuit, and the second input end of the voltage comparison circuit is connected with external input; the output end of the voltage comparison circuit is connected with the voltage output switch;

the reference voltage circuit is used for generating a reference voltage;

the voltage comparison circuit is used for determining a reference voltage range according to the reference voltage and comparing whether the input voltage is in the reference voltage range; if the input voltage is within the reference voltage range, triggering the voltage output switch to be switched off; and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed.

2. The apparatus of claim 1, wherein the reference voltage circuit comprises: a voltage stabilizing element; and the voltage stabilizing element is respectively connected with a power supply input end and the output end of the reference voltage circuit.

3. The apparatus of claim 1, wherein the voltage comparison circuit comprises: a first comparator and a second comparator; the first comparator and the second comparator are connected through a field effect tube;

the positive input end of the first comparator is connected with the input voltage through a first voltage regulating element, and the negative input end of the first comparator is connected with the output end of the reference voltage circuit; the first voltage regulating element is used for regulating the minimum value of the reference voltage range;

the positive input end of the second comparator is connected with the output end of the reference voltage circuit, and the negative input end of the second comparator is connected with the input voltage through a second voltage regulating element; the second voltage regulating element is used for regulating the maximum value of the reference voltage range.

4. The apparatus of claim 3, wherein the first voltage regulating element comprises a first resistor of a predetermined resistance; the second voltage regulating element comprises a second resistor with a preset resistance value.

5. The apparatus of claim 3, wherein the FET comprises two first and second MOS transistors connected to each other; the first MOS tube and the second MOS tube are both N-channel depletion type MOS tubes.

6. The apparatus of claim 5, wherein a gate of the first MOS transistor is connected to the output terminal of the first comparator, a drain of the first MOS transistor is connected to the voltage output switch, and a source of the first MOS transistor is connected to a drain of the second MOS transistor; and the grid electrode of the second MOS tube is connected with the output end of the second comparator.

7. The apparatus of claim 1, further comprising: a protection circuit; the protection circuit is connected with the external input; the protection circuit includes: a plurality of schottky diodes connected in parallel with each other.

8. The apparatus of claim 1, further comprising: a filter circuit; the filter circuit is connected with the external input; the filter circuit includes: a plurality of magnetic beads connected in parallel to each other.

9. The apparatus of claim 1, wherein the voltage output switch comprises: and the P-channel enhancement type MOS tube.

10. A method for preventing host damage, applied to a computer host, the method comprising:

after the input voltage is acquired, determining a reference voltage range according to the reference voltage, and comparing whether the input voltage is in the reference voltage range;

if the input voltage is within the reference voltage range, triggering the voltage output switch to be switched off;

and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed.

Technical Field

The invention belongs to the technical field of circuit protection, and particularly relates to a device and a method for preventing a host from being damaged.

Background

Direct current power supply is an indispensable power supply mode in the prior art, and for example, desktop computers, industrial personal computers, notebook computers and the like are generally set to be direct current power supply. In direct current power supply, the power input is generally a special configuration, the power output voltage is different according to different product designs, and the product generally designates the power when being shipped. However, in the actual use process, the user often uses a power supply that does not conform to the voltage required by the current host to supply power, so that the host is damaged by over-voltage or under-voltage and cannot be recovered.

Therefore, how to protect the computer from the damage of the host caused by the over-high or over-low voltage is an urgent technical problem to be solved in the prior art.

Disclosure of Invention

The invention provides a device and a method for preventing a host computer from being damaged, which aim to solve the technical problem that the host computer is damaged due to overhigh or overlow input voltage.

The technical scheme provided by the invention is as follows:

in one aspect, an apparatus for preventing damage to a host includes: the voltage comparison circuit, the reference voltage circuit and the voltage output switch; the first input end of the voltage comparison circuit is connected with the reference voltage circuit, and the second input end of the voltage comparison circuit is connected with the external input; the output end of the voltage comparison circuit is connected with the voltage output switch;

the reference voltage circuit is used for generating a reference voltage;

the voltage comparison circuit is used for determining a reference voltage range according to the reference voltage and comparing whether the input voltage is in the reference voltage range; if the input voltage is within the reference voltage range, triggering the voltage output switch to be switched off; and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed.

Optionally, the reference voltage circuit includes: a voltage stabilizing element; and the voltage stabilizing element is respectively connected with a power supply input end and the output end of the reference voltage circuit.

Optionally, the voltage comparison circuit includes: a first comparator and a second comparator; the first comparator and the second comparator are connected through a field effect tube;

the positive input end of the first comparator is connected with the input voltage through a first voltage regulating element, and the negative input end of the first comparator is connected with the output end of the reference voltage circuit; the first voltage regulating element is used for regulating the minimum value of the reference voltage range;

the positive input end of the second comparator is connected with the output end of the reference voltage circuit, and the negative input end of the second comparator is connected with the input voltage through a second voltage regulating element; the second voltage regulating element is used for regulating the maximum value of the reference voltage range.

Optionally, the first voltage regulating element includes a first resistor with a preset resistance value; the second voltage regulating element comprises a second resistor with a preset resistance value.

Optionally, the field effect transistor includes a first MOS transistor and a second MOS transistor that are connected to each other; the first MOS tube and the second MOS tube are both N-channel depletion type MOS tubes.

Optionally, the gate of the first MOS transistor is connected to the output end of the first comparator, the drain of the first MOS transistor is connected to the voltage output switch, and the source of the first MOS transistor is connected to the drain of the second MOS transistor; and the grid electrode of the second MOS tube is connected with the output end of the second comparator.

Optionally, the method further includes: a protection circuit; the protection circuit is connected with the external input; the protection circuit includes: a plurality of schottky diodes connected in parallel with each other.

Optionally, the method further includes: a filter circuit; the filter circuit is connected with the external input; the filter circuit includes: a plurality of magnetic beads connected in parallel to each other.

Optionally, the voltage output switch includes: and the P-channel enhancement type MOS tube.

In another aspect, a method for preventing damage to a host is applied to a host of a computer, and the method includes:

after the input voltage is acquired, determining a reference voltage range according to the reference voltage, and comparing whether the input voltage is in the reference voltage range;

if the input voltage is within the reference voltage range, triggering the voltage output switch to be switched off;

and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed.

The invention has the beneficial effects that:

the device and the method for preventing the host machine from being damaged provided by the embodiment of the invention are characterized in that a voltage comparison circuit, a reference voltage circuit and a voltage output switch are arranged on the device; the first input end of the voltage comparison circuit is connected with the reference voltage circuit, and the second input end of the voltage comparison circuit is connected with the external input; the output end of the voltage comparison circuit is connected with the voltage output switch; the reference voltage circuit is used for generating a reference voltage; the voltage comparison circuit is used for determining a reference voltage range according to the reference voltage and comparing whether the input voltage is in the reference voltage range; if the input voltage is within the reference voltage range, the voltage output switch is triggered to be switched off; and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed. This application is through detecting whether outside electrical input accords with the reference voltage scope to control the access of outside input, when outside input is not in the reference voltage scope, the break-off voltage goes out output switch, blocks being connected of outside input and host computer, thereby the protection host computer can not be because of input voltage is too high or low damage excessively, makes the host computer work when input voltage is normal voltage.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic diagram illustrating an operation principle of an apparatus for preventing a host from being damaged according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a working principle of a reference voltage circuit according to an embodiment of the present invention;

fig. 3 is a schematic diagram illustrating an operating principle of a voltage comparison circuit according to an embodiment of the present invention;

fig. 4 is a schematic diagram illustrating an operation principle of a voltage output switch according to an embodiment of the present invention;

fig. 5 is a flowchart illustrating a method for preventing a host from being damaged according to an embodiment of the present invention.

Reference numerals: 1-a reference voltage circuit; 2-a voltage comparison circuit; 3-voltage output switch.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

Direct current power supply is an indispensable power supply mode in the prior art, and for example, desktop computers, industrial personal computers, notebook computers and the like are generally set to be direct current power supply. In direct current power supply, the power input is generally a special configuration, the power output voltage is different according to different product designs, and the product generally designates the power when being shipped. However, in the actual use process, the user often uses a power supply that does not conform to the voltage required by the current host to supply power, so that the host is damaged by over-voltage or under-voltage and cannot be recovered.

Accordingly, the embodiment of the invention provides a device for preventing the host machine from being damaged.

Fig. 1 is a schematic diagram illustrating an operating principle of an apparatus for preventing a host from being damaged according to an embodiment of the present invention, and referring to fig. 1, the apparatus for preventing a host from being damaged according to the embodiment of the present invention includes: a voltage comparison circuit 2, a reference voltage circuit 1 and a voltage output switch 3; the first input end of the voltage comparison circuit is connected with the reference voltage circuit, and the second input end of the voltage comparison circuit is connected with the external input; the output end of the voltage comparison circuit is connected with the voltage output switch; the reference voltage circuit 1 is used for generating a reference voltage; a voltage comparison circuit 2 for determining a reference voltage range according to the reference voltage, and comparing whether the input voltage is within the reference voltage range; if the input voltage is within the reference voltage range, the voltage output switch is triggered to be switched off; and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed.

In a specific implementation process, the device for preventing the host from being damaged can be arranged at the power input end of any host, so that the host is prevented from being damaged.

For example, a reference voltage circuit may generate a reference voltage from which a voltage comparator circuit may determine a reference voltage range. The external input can be external direct current input (namely external DC input), after the external DC input, the voltage comparison circuit compares whether the external DC input is in a reference voltage range, if so, the external DC input is consistent with the voltage required by the host, and the voltage comparison circuit can supply power to the host, and then the voltage output switch is triggered to be closed, so that the power is supplied to the host; if the external DC input is not in the reference voltage range, the external DC input is not consistent with the voltage required by the host, and the host is possibly damaged when the host is powered, the voltage output switch is switched off, and the external DC input is forbidden to supply power to the host, so that the host is prevented from being damaged.

The device for preventing the host from being damaged provided by the embodiment of the invention is provided with a voltage comparison circuit, a reference voltage circuit and a voltage output switch; the first input end of the voltage comparison circuit is connected with the reference voltage circuit, and the second input end of the voltage comparison circuit is connected with the external input; the output end of the voltage comparison circuit is connected with the voltage output switch; the reference voltage circuit is used for generating a reference voltage; the voltage comparison circuit is used for determining a reference voltage range according to the reference voltage and comparing whether the input voltage is in the reference voltage range; if the input voltage is within the reference voltage range, the voltage output switch is triggered to be switched off; and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed. This application is through detecting whether outside electrical input accords with the reference voltage scope to control the access of outside input, when outside input is not in the reference voltage scope, the break-off voltage goes out output switch, blocks being connected of outside input and host computer, thereby the protection host computer can not be because of input voltage is too high or low damage excessively, makes the host computer work when input voltage is normal voltage.

Based on one general inventive concept, the embodiments of the present invention also provide another apparatus for preventing damage to a host.

Fig. 2 is a schematic diagram of an operating principle of a reference voltage circuit according to an embodiment of the present invention, referring to fig. 2, optionally, the apparatus for preventing damage to a host according to the embodiment of the present invention, the reference voltage circuit includes: a voltage stabilizing element; and the voltage stabilizing element is respectively connected with the power supply input end and the output end of the reference voltage circuit.

For example, the voltage regulator Q11 may be a TL431 series voltage regulator diode, such as TL431SOT23, to generate a reference voltage of 2.5V. It should be noted that the specific types of the voltage stabilizing elements of 2.5V are all listed here, and are not limited. Referring to fig. 2, IN order to achieve a voltage stabilizing effect, a resistor PR6 and a capacitor PC221 may be respectively connected to both ends 1 and 2 of the TL431SOT23, and the other end of the resistor PR6 is connected to a power supply + DC _ IN _ F; one end of the PC221 is connected to ground, and the other end is connected to 2.5V. The specific size of the resistor and the capacitor can be set as shown in fig. 2, which is not described herein. The reference voltage of 2.5V is labeled 2.5VREF in fig. 2.

Fig. 3 is a schematic diagram illustrating an operating principle of a voltage comparison circuit according to an embodiment of the present invention.

In some embodiments, optionally, referring to fig. 3, the voltage comparison circuit comprises: a first comparator U10A and a second comparator U10B; the first comparator and the second comparator are connected through a field effect tube; the positive input end of the first comparator is connected with an input voltage through a first voltage regulating element, and the negative input end of the first comparator is connected with the output end of the reference voltage circuit; the first voltage regulating element is used for regulating the minimum value of the reference voltage range; the positive input end of the second comparator is connected with the output end of the reference voltage circuit, and the negative input end of the second comparator is connected with the input voltage through the second voltage regulating element; the second voltage regulating element is used for regulating the maximum value of the reference voltage range.

In some embodiments, optionally, referring to fig. 3, the first voltage regulating element includes first resistors PR8 and PR10 with preset resistance values; the second voltage regulating element includes second resistors PR11 and PR12 having predetermined resistance values.

In some embodiments, optionally, referring to fig. 3, the fet includes two first MOS transistors Q10A and a second MOS transistor Q10B connected to each other; the first MOS tube and the second MOS tube are both N-channel depletion type MOS tubes.

In some embodiments, optionally, referring to fig. 3, the gate G1 of the first MOS transistor is connected to the output terminal 1 of the first comparator U10A, the drain D1 of the first MOS transistor is connected to the voltage output switch, and the source S1 of the first MOS transistor U10A is connected to the drain D2 of the second MOS transistor U10B; the gate G2 of the second MOS transistor U10B is connected to the output terminal 7 of the second comparator U10B.

Optionally, the voltage output switch includes: and the P-channel enhancement type MOS tube.

For example, referring to fig. 3, in the voltage comparison circuit, the first comparator and the second comparator are both set as LM358DR voltage comparators, and Q10A and Q10B are N-channel depletion type MOSFET devices that are in an on state when GS is 0.

Fig. 4 is a schematic diagram of an operating principle of a voltage output switch according to an embodiment of the present invention.

For example, referring to fig. 3 and 4, the voltage output switch may be set to PK501BA, which is a P-channel enhancement MOSFET device, which is turned off in the GS-0 state and is controlled to turn on when a voltage is applied to the G-pole.

The working principle is explained in the invention: the input voltage + DC _ IN _ F is divided by the resistor PR8 and the resistor PR10 and compared with 2.5 VREF. According to the resistance values of the resistor PR8 and the resistor PR10, the minimum value of the reference voltage in the voltage comparison circuit can be set to be 15.6V; according to the resistance values of the resistor PR11 and the resistor PR12, the maximum value of the reference voltage in the voltage comparison circuit can be set to be 21.25V. It should be noted that the maximum and minimum values are specific values listed according to the resistance values of the listed voltage regulating elements, and are not limited.

When 21.25V > + DC _ IN _ F >15.6V, the output of U10A is high, Q10A is on; the U10B output is high, Q10B is on; PQ4 is on; the + VDC _ SYS voltage of the output voltage of the access host is normal.

When + DC _ IN _ F <15.6V, the output of U10A is low, Q10A is off; the U10B output is high, Q10B is on; PQ4 cutoff; + VDC _ SYS is 0.

When + DC _ IN _ F >21.25V, the output of U10A is high, Q10A is on; the U10B output is low, Q10B is off; PQ4 cutoff; + VDC _ SYS is 0.

In the embodiment of the invention, the range of the reference voltage can be adjusted by adjusting the size of the voltage adjusting element. For example, PR10 can adjust the low pressure range by adjusting PR 8; by adjusting PR11, PR12 can adjust the high pressure range. Therefore, the adjustment range of the input voltage is realized, and the protection effect on the main board of the host is enhanced.

Referring to fig. 3, in the voltage comparison circuit, in order to ensure the operation effect of the circuit, resistors PR3, PR1, PR4, PR2 and capacitors PC21, PC17 may be further provided, and the specific connection relationship and size of the circuit may be set conventionally, and refer to fig. 3, which is not described herein.

In some embodiments, optionally, the method further includes: a protection circuit; the protection circuit is connected with the external input; the protection circuit includes: a plurality of schottky diodes connected in parallel with each other.

For example, referring to fig. 4, the protection circuit may be schottky diodes SP9-SP12 connected in parallel with each other, and the bonding may be provided in a SHORT PAD, and the specific connection relationship, referring to fig. 4, is connected to the power source.

In some embodiments, optionally, the method further includes: a filter circuit; the filter circuit is connected with the external input; the filter circuit includes: a plurality of magnetic beads connected in parallel to each other.

For example, referring to fig. 4, the filter circuit may include magnetic beads PFB1-PFB3 connected in parallel with each other, and capacitors PC22 and PC23 are provided to achieve a filtering effect. Specific setting sizes of the capacitor and the magnetic bead can be referred to fig. 4, which is not described herein.

Further, referring to fig. 3 and 4, the voltage comparison circuit is connected through a resistor PR 7. In the circuit diagram of the voltage output switch, resistors PF9, PR195, PQ402, capacitors PC24, PC212, C0402, PC18, PC19, PC20, and PEC2 may also be provided, and specific resistor-capacitor connection modes and selection sizes may refer to fig. 4, which is not described herein again.

The device for preventing the host from being damaged provided by the embodiment of the invention is provided with a voltage comparison circuit, a reference voltage circuit and a voltage output switch; the first input end of the voltage comparison circuit is connected with the reference voltage circuit, and the second input end of the voltage comparison circuit is connected with the external input; the output end of the voltage comparison circuit is connected with the voltage output switch; the reference voltage circuit is used for generating a reference voltage; the voltage comparison circuit is used for determining a reference voltage range according to the reference voltage and comparing whether the input voltage is in the reference voltage range; if the input voltage is within the reference voltage range, the voltage output switch is triggered to be switched off; and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed. This application is through detecting whether outside electrical input accords with the reference voltage scope to control the access of outside input, when outside input is not in the reference voltage scope, the break-off voltage goes out output switch, blocks being connected of outside input and host computer, thereby the protection host computer can not be because of input voltage is too high or low damage excessively, makes the host computer work when input voltage is normal voltage.

Based on a general inventive concept, embodiments of the present invention also provide a method for preventing damage to a host.

Fig. 5 is a flowchart illustrating a method for preventing a host from being damaged according to an embodiment of the present invention, and referring to fig. 5, the method for preventing a host from being damaged according to an embodiment of the present invention is applied to a host computer, and the method may include the following steps:

s1, after the input voltage is obtained, determining a reference voltage range according to the reference voltage, and comparing whether the input voltage is in the reference voltage range;

s2, if the input voltage is in the reference voltage range, the voltage output switch is triggered to be switched off;

and S3, if the input voltage is not in the reference voltage range, the trigger voltage output switch is closed.

According to the method for preventing the host from being damaged, after the input voltage is obtained, the reference voltage range is determined according to the reference voltage, and whether the input voltage is in the reference voltage range is compared; if the input voltage is within the reference voltage range, the voltage output switch is triggered to be switched off; and if the input voltage is not in the reference voltage range, triggering the voltage output switch to be closed. This application is through detecting whether outside electrical input accords with the reference voltage scope to control the access of outside input, when outside input is not in the reference voltage scope, the break-off voltage goes out output switch, blocks being connected of outside input and host computer, thereby the protection host computer can not be because of input voltage is too high or low damage excessively, makes the host computer work when input voltage is normal voltage.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

It is understood that the same or similar parts in the above embodiments may be mutually referred to, and the same or similar parts in other embodiments may be referred to for the content which is not described in detail in some embodiments.

It should be noted that the terms "first," "second," and the like in the description of the present invention are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Further, in the description of the present invention, the meaning of "a plurality" means at least two unless otherwise specified.

Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and alternate implementations are included within the scope of the preferred embodiment of the present invention in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present invention.

It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.

It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when the program is executed, the program includes one or a combination of the steps of the method embodiments.

In addition, functional units in the embodiments of the present invention may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.

The storage medium mentioned above may be a read-only memory, a magnetic or optical disk, etc.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.