Handheld device capable of automatically switching between a handheld mode and a non-handheld mode and control method thereof

This application is a divisional application of, and claims the priority benefit of, U.S. application Ser. No. 13/038,367 filed on Mar. 1, 2011.

1. Field of the Invention

The present invention relates to a handheld device capable of automatically switching handheld mode/non-handheld mode and related control methods, and more particularly, to a handheld device and related control methods for sensing whether a user touch is received or not via a sensing unit and for controlling the sensing unit via a control unit in order to differentiate handheld behaviors from non-handheld behaviors.

2. Description of the Prior Art

With the flourish developments of the wireless communication network in the modern information society, handheld devices, such as mobile phones and personal digital assistants (PDAs) have become one of the most popular communication tools. However, although the handheld device is defined as “a device to be held by a hand of a user”, the existing handheld device itself is unable to know whether it is held by the hand of a user and is unable to automatically adjust settings of the handheld device in response to “handheld behaviors” and “non-handheld behaviors”. For this reason, it's a “smart” handheld device cannot be created, which causes inconvenience to the users in many applications.

Hence, how to enhance the convenience of the handheld devices and add more functionality to the handheld devices have become one of important topics in this field.

It is one of the objectives of the claimed invention to provide a handheld device capable of automatically switching handheld mode/non-handheld mode and related control methods to solve the abovementioned problems.

According to one embodiment, a handheld device capable of automatically switching handheld mode/non-handheld mode is provided. The handheld device may include a sensing unit, a control unit, an operating unit, a counting module and a mode control unit. The sensing unit is arranged for generating a sensing result based on whether a user touch is received or not. The control unit is arranged for sending out a periodic pulse to the sensing unit, and for making use of the periodic pulse to periodically charge and discharge the sensing unit. The counting module is coupled to the control unit and the sensing unit, and is arranged for counting a pulse number of the periodic pulse, and for outputting a counting value when the sensing result indicates that the user touch is received. The operating unit is coupled to the counting module, and is arranged for generating a mode control signal according to the counting value. The mode control unit is coupled to the operating unit, and is arranged for controlling the handheld device to stay in a handheld mode or a non-handheld mode according to the mode control signal. In one embodiment, the counting module may include a counter and a voltage comparator.

According to another embodiment, a method for controlling modes of a handheld device is provided. The method includes the following steps: sending out a periodic pulse to a sensing unit, and making use of the periodic pulse to periodically charge and discharge the sensing unit; the sensing unit generating a sensing result based on whether a user touch is received or not; counting a pulse number of the periodic pulse, and outputting a counting value when the sensing result indicates that the user touch is received; generating a mode control signal according to the counting value; and controlling the handheld device to stay in a handheld mode or a non-handheld mode according to the mode control signal.

These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.

FIG. 1 is diagram of a handheld device capable of automatically switching handheld mode/non-handheld mode according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating the handheld device shown in FIG. 1 according to a first embodiment of the present invention.

FIG. 3 is a diagram showing signal waveforms of the sensing voltage generated by the sensing unit shown in FIG. 2 under a first condition that a user touch is not received and a second condition that a user touch is received.

FIG. 4 is a block diagram illustrating the handheld device shown in FIG. 1 according to a second embodiment of the present invention.

FIG. 5 is a diagram showing signal waveforms of the sensing voltage generated by the sensing unit shown in FIG. 4 during the discharging stage and the charging stage (including a first condition that a user touch is not received and a second condition that a user touch is received).

FIG. 6 is a flowchart illustrating a method for controlling modes of a handheld device according to an exemplary embodiment of the present invention.

FIG. 7 is a flowchart illustrating a method for controlling modes of a handheld device according to another exemplary embodiment of the present invention.

Please refer to FIG. 1 together with FIG. 2 . FIG. 1 is diagram of a handheld device 100 capable of automatically switching handheld mode/non-handheld mode according to an embodiment of the present invention, and FIG. 2 is a block diagram illustrating the handheld device 100 shown in FIG. 1 according to a first embodiment of the present invention. As shown in FIG. 1 , the handheld device 100 may include a control unit 110 and a sensing unit 120 . In this embodiment, the sensing unit 120 may be implemented by a conductive material, wherein the conductive material may be attached to the outside surface of the housing of the handheld device 100 or may be embedded in the housing of the handheld device 100 . In addition, the sensing unit 120 can be used for sensing whether a user touch is received or not by way of indirect induction or direct contact. The control unit 110 is coupled to the sensing unit 120 , and is arranged for controlling operations of the sensing unit 120 .

As shown in FIG. 2 , the handheld device 100 may include, but is not limited to, a control unit 110 , a sensing unit 120 , an operating unit 130 , and a mode control unit 140 . The control unit 110 is arranged for sending out a charging-and-discharging signal Scharge to the sensing unit 120 , and for making use of the charging-and-discharging signal Scharge to charge and discharge the sensing unit 120 . In this embodiment, the charging-and-discharging signal Scharge may be a periodic pulse, and thus the control unit 110 may utilize the periodic pulse to periodically charge and discharge the sensing unit 120 . The sensing unit 120 is coupled to the control unit 110 , and may be arranged for generating a sensing result based on whether a user touch is received or not. In this embodiment, the sensing result generated by the sensing unit 120 may be implemented by a sensing voltage Vs, but this in no way should be a limitation of the present invention. After that, the operating unit 130 is coupled to the sensing unit 120 , and is arranged for generating a mode control signal SC to the mode control unit 140 according to the sensing result (i.e., the sensing voltage Vs). The mode control unit 140 is coupled to the operating unit 130 , and is arranged for controlling the handheld device 100 to stay in a handheld mode MD 1 or a non-handheld mode MD 2 according to the mode control signal SC.

In this embodiment, the operating unit 130 may be implemented by a voltage comparator (e.g., 132 ), but this in no way should be a limitation of the present invention. The voltage comparator 132 is arranged for comparing the sensing voltage Vs with a threshold voltage V TH in order to generate the mode control signal SC to the mode control unit 140 . For example, when the sensing voltage Vs is smaller than the threshold voltage V TH (i.e., Vs<V TH ), the mode control signal SC has a first logic level (such as, “1”). At this time, the mode control unit 140 may control the handheld device 100 to stay in the handheld mode MD 1 according to the mode control signal SC with the first logic level. On the contrary, when the sensing voltage Vs is not smaller than the threshold voltage V TH (i.e., Vs≧V TH ), the mode control signal SC has a second logic level (such as, “0”). At this time, the mode control unit 140 may control the handheld device 100 to stay in the non-handheld mode MD 2 according to the mode control signal SC with the second logic level.

Please note that, the handheld device 100 disclosed in the present invention utilizes the sensing unit 120 (which may be implemented by a conductive material attached to the outside surface of the housing of the handheld device 100 or embedded in the housing of the handheld device 100 ) to sense whether a user touch is received or not, and utilizes the control unit 110 to charge and discharge the sensing unit 120 so as to achieve the goal of differentiating handheld behaviors from non-handheld behaviors. For example, please also refer to FIG. 3 . FIG. 3 is a diagram showing signal waveforms of the sensing voltage Vs generated by the sensing unit 120 shown in FIG. 2 under a first condition that a user touch is not received and a second condition that a user touch is received. Under a condition that the fingers or body of a user do not touch the sensing unit 120 of the handheld device 100 (that is, the condition that a user touch is not received), because the control unit 110 may make use of the charging-and-discharging signal Scharge to periodcially charge and discharge the sensing unit 120 , the control unit 110 and the sensing unit 120 may form a charging path during a charging stage, and the control unit 110 and the sensing unit 120 may form a discharging path during a discharging stage. Therefore, the sensing voltage Vs of the sensing unit 120 can be maintained at a fixed potential V 1 , such as a first curve S 1 shown in FIG. 3 . Under a condition that the fingers or body of a user touch the sensing unit 120 of the handheld device 100 (that is, the condition that a user touch is received), the discharging path and discharging loop of the sensing unit 120 will be changed. In other words, the fingers or body of the user, the control unit 110 , the sensing unit 120 , and the ground terminal may form another discharging path, and the handheld device 100 may lead out electric charges of the sensing unit 120 via the new discharging path. Therefore, the potential of the sensing voltage Vs of the sensing unit 120 will be changed (decreased), such as a second curve S 2 shown in FIG. 3 . That is, the sensing voltage Vs of the sensing unit 120 will be lowered down to another potential V 2 .

Please note that, the abovementioned handheld device 100 may be a mobile phone, a personal digital assistant (PDA), a PDA phone, or a smart phone. But the present invention is not limited to this only, and it can be implemented by a handheld device of other types. Moreover, the abovementioned handheld mode MD 1 /non-handheld mode MD 2 can be related to application settings of the handheld device 100 , such as: call vibration control, auto-switch between speaker mode and handheld mode, and volume control. Those skilled in the art should appreciate that various modifications of the handheld mode MD 1 and the non-handheld mode MD 2 may be made, which can be designed depending upon actual demands.

Please refer to FIG. 4 . FIG. 4 is a block diagram illustrating the handheld device shown in FIG. 1 according to a second embodiment of the present invention. In this embodiment, the handheld device 400 may include, but is not limited to, a control unit 410 , a sensing unit 420 , an operating unit 430 , a mode control unit 440 , a counting module 450 , a first switch SW 1 , and a second switch SW 2 . The operations of the control unit 410 and the sensing unit 420 shown in FIG. 4 are similar to the operations of the control unit 110 and the sensing unit 120 shown in FIG. 2 , and the same description is omitted here for brevity. What calls for special attention is that: the control unit 410 is further arranged for generating an enable signal EN to the counting module 450 , for generating a first switch signal SS 1 to the first switch SW 1 , and for generating a second switch signal SS 2 to the second switch SW 2 . The counting module 450 is coupled to the control unit 410 and the sensing unit 420 . When the enable signal EN is received by the counting module 450 , the counting module 450 may start counting a pulse number of the charging-and-discharging signal Scharge (such as, a periodic pulse) sent by the control unit 410 . When a user touch is received by the sensing unit 420 , the counting module 450 may stop counting the pulse number of the charging-and-discharging signal Scharge (such as, a periodic pulse) in order to output a counting value Nc, wherein the counting value Nc is corresponding to a counting time. After that, the operating unit 430 is coupled to the counting module 450 , and is arranged for generating a mode control signal Sc to the mode control unit 440 according to the counting value Nc (or the corresponding counting time). The mode control unit 440 is coupled to the operating unit 430 , and is arranged for controlling the handheld device 400 to stay in a handheld mode MD 1 or a non-handheld mode MD 2 according to the mode control signal SC.

In this embodiment, the counting module 450 may be implemented by a voltage comparator 452 and a counter 454 . The voltage comparator 452 is arranged for comparing the sensing voltage Vs with a threshold voltage V TH in order to determine whether to output a disable signal #EN. For example, when the sensing voltage Vs is greater than the threshold voltage V TH , the voltage comparator 452 will output the disable signal #EN to the counter 454 ; and when the sensing voltage Vs is not greater than the threshold voltage V TH , the voltage comparator 452 will not output the disable signal #EN to the counter 454 . The counter 454 is coupled to the voltage comparator 452 , and is arranged for starting counting the pulse number of the charging-and-discharging signal Scharge (e.g., a periodic pulse) when the enable signal EN is received, and for stopping counting the pulse number of the charging-and-discharging signal Scharge to obtain the counting value Nc (or the corresponding counting time) when the disable signal #EN is received.

In addition, the operating unit 430 can be implemented by a comparator (e.g., 432 ), but the present invention is not limited to this only. The comparator 432 compares the counting value Nc with a threshold value N TH in order to generate the mode control signal SC to the mode control unit 440 . For example, when the counting value Nc is smaller than the threshold value N TH (i.e., Nc<N TH ), the mode control signal SC has a first logic level (such as, “1”). At this time, the mode control unit 440 may utilize the mode control signal SC with the first logic level to control the handheld device 400 to stay in the handheld mode MD 1 . On the contrary, when the counting value Nc is not smaller than the threshold value N TH (i.e., Nc≧N TH ), the mode control signal SC has a second logic level (such as, “0”). At this time, the mode control unit 440 may utilize the mode control signal SC with the second logic level to control the handheld device 400 to stay in the non-handheld mode MD 2 .

Furthermore, the first switch SW 1 is coupled between the control unit 410 and the sensing unit 420 . The control unit 410 is further arranged for determining whether to turn on or turn off the first switch SW 1 according to the first switch signal SS 1 in order to determine whether to transmit the charging-and-discharging signal Scharge to the sensing unit 420 . The second switch SW 2 is coupled between the sensing unit 420 and a ground terminal. The control unit 410 is further arranged for determining whether to turn on or turn off the second switch SW 2 according to the second switch signal SS 2 . What calls for special attention is that: during a charging stage, the first switch SW 1 is turned on and the second switch SW 2 is turned off. At this time, the control unit 410 , the first switch SW 1 , and the sensing unit 420 form a charging path. During a discharging stage, the first switch SW 1 is turned off and the second switch SW 2 is turned on. At this time, the second switch SW 2 and the sensing unit 420 form a discharging path.

Please also refer to FIG. 5 . FIG. 5 is a diagram showing signal waveforms of the sensing voltage Vs generated by the sensing unit 420 shown in FIG. 4 during the discharging stage and the charging stage (including a first condition that a user touch is not received and a second condition that a user touch is received). First, during the discharging stage, the electronic charges on the conductive material of the sensing unit 420 are exhausted through the discharging path, such as a fifth curve S 5 shown in FIG. 5 . After that, the charging path is connected during the charging stage. In the following descriptions, two conditions are cited for illustration. Under a first condition that the fingers or body of a user do not touch the sensing unit 420 of the handheld device 400 (that is, the condition that a user touch is not received), because the control unit 410 may make use of the charging-and-discharging signal Scharge to periodcially charge and discharge the sensing unit 420 , the sensing voltage Vs of the sensing unit 420 will be charged to reach a predetermined potential VD within a time period t 1 (at this time, the counting value Nc is corresponding to a pulse number of N1 pulses), such as a third curve S 3 shown in FIG. 5 . Under a second condition that the fingers or body of the user do touch the sensing unit 420 of the handheld device 400 (that is, the condition that a user touch is received), the equivalent charge quantity will be changed due to the touch of the fingers or body of the user. For this reason, the charging time of the sensing unit 420 will be changed. At this time, after a time period t 2 (at this time, the counting value Nc is corresponding to a pulse number of N2 pulses), the sensing unit 420 will be charged to reach the predetermined potential VD, such as a fourth curve S 4 shown in FIG. 5 .

In one word, in the abovementioned first embodiment, under the condition that the fingers or body of the user do not touch the sensing unit 120 of the handheld device 100 , the sensing voltage Vs will be maintained at the potential V 1 and is not smaller than the threshold voltage V TH (i.e., Vs≧V TH ). At this time, the mode control unit 140 may control the handheld device 100 to stay in the non-handheld mode MD 2 . Under the condition that the fingers or body of the user do touch the sensing unit 120 of the handheld device 100 , the sensing voltage Vs will be lowered down to the potential V 2 and is smaller than the threshold voltage V TH (i.e., Vs<V TH ). At this time, the mode control unit 140 may control the handheld device 100 to stay in the handheld mode MD 1 .

Besides, in the abovementioned second embodiment, under the condition that the fingers or body of the user do not touch the sensing unit 420 of the handheld device 400 , the sensing voltage Vs of the sensing unit 420 will be charged to reach the predetermined potential VD after the time period t 1 . That is to say, the counting value Nc (or the counting time) obtained by the counting module 450 is smaller (i.e., Nc<N TH ). At this time, the mode control unit 440 may control the handheld device 400 to stay in the non-handheld mode MD 2 . Under the condition that the fingers or body of the user do touch the sensing unit 420 of the handheld device 400 , the sensing voltage Vs of the sensing unit 420 will be charged to reach the predetermined potential VD after the time period t 2 . That is to say, the counting value Nc (or the counting time) obtained by the counting module 450 is larger (i.e., Nc≧N TH ). At this time, the mode control unit 440 may control the handheld device 400 to stay in the handheld mode MD 1 . Therefore, the handheld device 100 / 400 can achieve a goal of automatically switching or controlling the handheld mode/non-handheld mode, which can add more functionality to the handheld device 100 / 400 and bring more convenience to the user.

Please refer to FIG. 6 . FIG. 6 is a flowchart illustrating a method for controlling modes of a handheld device according to an exemplary embodiment of the present invention. Please note that the following steps are not limited to be performed according to the exact sequence shown in FIG. 6 if a roughly identical result can be obtained. The method includes, but is not limited to, the following steps:

Step S 602 : Send out a charging-and-discharging signal to a sensing unit, and make use of the charging-and-discharging signal to charge and discharge the sensing unit.

Step S 604 : The sensing unit generates a sensing result (a sensing voltage) based on whether a user touch is received or not.

Step S 606 : Compare the sensing voltage with a threshold voltage. When the sensing voltage is smaller than the threshold voltage, go to the step S 610 ; otherwise, go to the step S 620 .

Step S 610 : When the sensing voltage is smaller than the threshold voltage, generate a mode control signal with a first logic level.

Step S 612 : Control the handheld device to stay in a handheld mode according to the mode control signal with the first logic level.

Step S 620 : When the sensing voltage is not smaller than the threshold voltage, generate a mode control signal with a second logic level.

Step S 622 : Control the handheld device to stay in a non-handheld mode according to the mode control signal with the second logic level.

How each element operates can be known by combining the steps shown in FIG. 6 together with the elements shown in FIG. 1 and FIG. 2 and the signal waveforms shown in FIG. 3 . Therefore, further description for the operations of the steps shown in FIG. 6 is omitted here for brevity. Please note that: the steps S 610 ˜S 612 represent the condition that the handheld device 100 is under the handheld mode MD 1 , and the steps S 620 ˜S 622 represent the condition that the handheld device 100 is under the non-handheld mode MD 2 .

Please refer to FIG. 7 . FIG. 7 is a flowchart illustrating a method for controlling modes of a handheld device according to another exemplary embodiment of the present invention. The method includes, but is not limited to, the following steps:

Step S 702 : Send out a periodic pulse to a sensing unit, and make use of the periodic pulse to periodically charge and discharge the sensing unit.

Step S 704 : The sensing unit generates a sensing result based on whether a user touch is received or not.

Step S 706 : Count a pulse number of the periodic pulse, and output a counting value when the sensing result indicates that the user touch is received.

Step S 708 : Compare the counting value with a threshold value. When the counting value is greater than the threshold value, go to the step S 710 ; otherwise, go to the step S 720 .

Step S 710 : When the counting value is greater than the threshold value, generate the mode control signal with a first logic level.

Step S 712 : Control the handheld device to stay in a handheld mode according to the mode control signal with the first logic level.

Step S 720 : When the counting value is not greater than the threshold value, generate the mode control signal with a second logic level.

Step S 722 : Control the handheld device to stay in a non-handheld mode according to the mode control signal with the second logic level.

How each element operates can be known by combining the steps shown in FIG. 7 together with the elements shown in FIG. 1 and FIG. 4 and the signal waveforms shown in FIG. 5 . Therefore, further description for the operations of the steps shown in FIG. 7 is omitted here for brevity. Please note that: the steps S 710 ˜S 712 represent the condition that the handheld device 400 is under the handheld mode MD 1 , and the steps S 720 ˜S 722 represent the condition that the handheld device 400 is under the non-handheld mode MD 2 .

Please note that, the steps of the abovementioned flowchart are merely practicable embodiments of the present invention, and in no way should be considered to be limitations of the scope of the present invention. These methods can include other intermediate steps or several steps can be merged into a single step without departing from the spirit of the present invention.

The abovementioned embodiments are presented merely for describing features of the present invention, and in no way should be considered to be limitations of the scope of the present invention. In summary, the present invention provides a handheld device capable of automatically switching between a handheld mode and a non-handheld mode and a related control method. By using a sensing unit (which can be implemented by a conductive material attached to the outside surface of the housing of the handheld device or embedded in the housing of the handheld device) to sense whether a user touch is received, and by using a control unit to charge and discharge the sensing unit, the original discharging path and electric charges will be changed under the condition that the sensing unit (such as, the conductive material) of the handheld device is touched by the fingers or body of the user, such that handheld behaviors and non-handheld behaviors can be differentiated. Therefore, the settings of the handheld device can be automatically adjusted in response to the handheld behaviors and the non-handheld behaviors. For example, application functions such as: call vibration control, auto-switch between speaker mode and handheld mode, and volume control can be added to the handheld device. As a result, the mechanism disclosed in the present invention can add more functionality to the handheld device and bring more convenience to the user.

Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.