JP5358957B2 - Electronics - Google Patents

Description

  The present invention relates to an electronic device.

  When a portable device such as a cellular phone or PHS is worn by a human or carried in a bag, a key may be pressed against the user's intention. For example, in the case of a foldable mobile phone, when the upper case is pressed in a folded state, the upper case is bent, and a key disposed on the lower case is pressed, The key may continue to be pressed if it is closed with an object sandwiched between the lower housings.

In this way, when a key is pressed against the user's will, the function assigned to the key is not executed, so that the key is pressed when the portable device is closed, A mobile phone that invalidates the key operation has been proposed (see, for example, Patent Document 1).
Japanese Patent Publication No. 5-44217

  In the invention described in Patent Document 1, even when a key is pressed when the portable wireless telephone is closed, processing by software is performed so that the key input operation is ignored. However, there is a problem that when the key is pressed, the key switch is turned on, and current consumption for key detection occurs. In particular, in a portable electronic device driven by a battery such as a mobile phone or a PHS, the battery life is deteriorated due to such wasteful current consumption. In addition, since the key input operation is set to be ignored, it is difficult for the user to notice that the key is continuously pressed, and a state where current consumption for detecting the key is generated may continue for a long time. There is. Further, there is a problem that it is necessary to perform processing for invalidating the key by detecting that the key is pressed.

  SUMMARY An advantage of some aspects of the invention is that it provides an electronic device with reduced current consumption for detecting a key that is pressed down where the user does not intend.

  In order to achieve the above object, an electronic device according to the present invention is an electronic device that disables a predetermined key in accordance with the state of its own device, and includes a key and a key switch provided corresponding to the key. A first wiring connected to one end of the key switch, a second wiring connected to the other end, and a state where the key is pressed and a state where the key is not pressed are connected to the key switch. A key press detecting means for detecting whether the voltage level of the second wiring is high or low, and a state in which the key is pressed when the state of the own device matches a condition for invalidating a predetermined key However, it is characterized by having control means for controlling the voltage level of the second wiring connected to the key switch corresponding to the key to be the same High or Low even when not pressed.

  ADVANTAGE OF THE INVENTION According to this invention, the electronic device which reduced the consumption current which detects the key pressed in the place which a user does not intend can be provided.

  Hereinafter, a mobile phone as an example of an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is an external view of a mobile phone as an example of an embodiment of the present invention. The cellular phone 1 can be opened and closed because the upper casing provided with the display 11 and the lower casing provided with the keys are connected by a hinge. The keys provided on the lower housing include a main key 12a such as a numeric keypad and direction keys, a side key 12b provided on the side surface of the lower housing, and a power key 12c.

  FIG. 2 is an external view of the mobile phone 1 in a state where the upper casing is rotated so that the upper casing and the lower casing overlap each other. As shown in FIG. 2A, the cellular phone 1 is folded so that the surface of the upper housing provided with the display 11 and the surface of the lower housing provided with the main key 12a are opposed to each other. Can be closed. Moreover, as shown in FIG.2 (b), it can also fold so that the back surface of an upper housing | casing and the back surface of a lower housing may oppose. Thereafter, the folded state as shown in FIG. 2 (a) is closed, the folded state as shown in FIG. 2 (b) is folded, and the upper housing and the lower housing are not overlapped (for example, The state in FIG. 1 is referred to as an open state.

  FIG. 3 is a block diagram showing the configuration of the mobile phone 1. The cellular phone 1 includes a control unit 51, a storage unit 52, an operation unit 53, a communication unit 54, a signal processing unit 55, a voice input / output unit 56, a display unit 57, a power supply control unit 58, and a broadcast reception unit 59, and a battery. Drive by 2.

  The control unit 51 includes a CPU and the like, and controls the entire mobile phone 1. The control unit 51 includes a key detection unit 81 that detects key presses and an open / close detection unit 82 that detects opening / closing of the mobile phone 1.

  The open / close detection unit 82 includes, for example, a hall sensor and a magnet. A hall sensor is provided in one of the upper housing and the lower housing, and a magnet is provided in the other, so that a closed state or an open state can be detected by a change in magnetic field. To detect.

  The key detection unit 81 detects a key operation of the operation unit 53 including the main key 12a, the side key 12b, and the power key 12c. The key detection unit 81 includes a key detection circuit for the main key 12a, a key detection circuit for the side key 12b, and a key detection circuit for the power key 12c, and detects each key pressing state. A method for detecting the key press state will be described later.

  In response to key detection by the key detection unit 81, for example, image data stored in the storage unit 52 can be read, and the display unit 57 can be controlled to display on the display. Alternatively, the broadcast receiving unit 59 is controlled to receive a television broadcast wave to perform decoding processing, the display unit 57 is controlled to display an image on the display, and the audio input / output unit 56 is controlled to output from the speaker. Sound can be output.

  Further, when a voice call is started by a key operation on the operation unit 53, as a transmission process, the control unit 51 controls the voice input / output unit 56 to collect sound from the microphone and to obtain an original signal of the voice signal And control the signal processing unit 55 to perform encoding and error countermeasure processing on the original signal, control the communication unit 54 to transmit the signal processed by the signal processing unit 55 and receive As processing, the signal received by the communication unit 54 is controlled by the signal processing unit 55 to perform decoding and error correction processing, and the audio input / output unit 56 is controlled to output sound from the receiver.

The key and the key detection method of the mobile phone 1 having such a configuration will be described in detail.
FIG. 4 is a diagram showing a configuration of a key switch corresponding to the main key 12a and a key detection circuit connected to these key switches and performing key detection.

  The main key 12a is provided with key switches 211 to 222 corresponding to the respective keys, which are arranged in a matrix to form a key matrix 200. Further, one end of each key switch is connected to the wiring in the column direction (line a to line d), and the other end is connected to the wiring in the row direction (line e to line g).

  The input ports (port E to port G) of the key detection circuit are connected to wirings (line e to line g) in the row direction of the key matrix, and the voltage levels of the detection control signals input by the respective wirings are Reads High or Low and detects key press. The input port has a pull-up resistor 111, and the wiring in the row direction connected to each key switch of the key matrix 200 is connected to the pull-up resistor 111. When not pressed, the voltage level of the detection control signal is High.

  The output ports (port A to port D) of the key detection circuit are connected to the wiring (lines a to d) in the column direction of the key matrix, and output search control signals. The output port includes an output buffer 101, an input buffer 102, a pull-up resistor 103, and a transistor 104.

  The output port can switch between a state where the output buffer 101 is valid and a state where the input buffer 102 is valid. In addition, the pull-up resistor 103 can be enabled or disabled by switching the transistor 104 ON / OFF.

  A method for detecting key presses in this key detection circuit will be described. In any of the output ports, the pull-up resistor 103 is normally disabled by turning off the transistor 104. Further, the output buffer 101 is set to an effective output mode, and a Low signal is input to the output buffer. As a result, a search control signal having a low voltage level is output from the output port.

  Here, when it is detected that any one of the key switches 211 to 222 is turned on, a low search control signal is sequentially output from each of the ports A to D, and which key switch is controlled. Specify whether it is ON. For example, when the key switch 211 is in an ON state, when a low search control signal is output from the port D, the voltage level of the line d becomes Low, and the key switch 211 is turned on to be connected. A current flows through the signal line, and the voltage level of the line e changes from High to Low.

Then, the port E detects the Low detection control signal and specifies that the key switch 211 is ON.

  When the casing of the mobile phone 1 is in an open state, there is a possibility that an operation by the user is input using the main key 12a. Therefore, as described above, the output port always outputs a low search control signal to detect the state where any of the key switches 211 to 222 is ON, and the state where any of the key switches 211 to 222 is ON. Then, a low search control signal is sequentially output to the port A to the port D to identify the ON key switch.

  On the other hand, when the casing of the mobile phone 1 is in the closed state, the main key 12a is covered with the upper casing of the mobile phone 1. Therefore, when the main key 12a is pressed with the cellular phone 1 closed, it is not intentionally pressed by the user to instruct some operation, but the upper casing of the cellular phone 1 is bent. There is a high possibility that the user has unintentionally pressed down, for example, when the user presses it or when the cellular phone 1 is closed and the object is pressed between them.

  Therefore, when the open / close detection unit 82 detects that the cellular phone 1 is closed, the pull-up resistor 103 is enabled by turning on the transistors 104 of all the output ports, and the output buffer 101 is disabled. Turn into. As a result, the control signal for searching for key depression of the main key 12a is in an input state, and the voltage level is in a high state.

  Here, since the input port is always in the input mode and the pull-up resistor 111 is connected, the control signal for detecting key presses of the key switches 211 to 222 is also in the input state. The voltage level is high.

  As described above, since the search control signal and the detection amount control signal have the same high voltage level, even if the key switch is pressed, lines in the row direction of the key matrix 200 (line e to line g). The voltage level of the detection control signal does not change, and generation of useless current consumption can be suppressed.

  In addition, when the cellular phone 1 is closed, it is not detected that the key switches 211 to 222 are in the ON state, so that the functions of the cellular phone 1 can be prevented from being executed without the user's intention. According to this method, even when the fact that the main key 12a is pressed by software is invalidated, key detection is not performed in the first place, so that useless processing can be reduced.

  When the cellular phone 1 is in the folded state as shown in FIG. 2B, for example, it is assumed that the television function is operated. At this time, it is difficult to operate the main key 12a while viewing the video displayed on the display 11. In this folded state, when the user holds the mobile phone 1, there is a high possibility that some main key 12a is pressed.

  Therefore, when the open / close detection unit 82 detects the folded state, similarly to the closed state, control is performed so that the input buffer 102 operates and the pull-up resistor 103 is connected. As a result, the key detection of the main key 12a is not performed in the folded state, and even if the main key 12a is pressed, the voltage level of the detection control signal for the lines e to g that is input to the input port does not change. Current consumption does not occur.

  As a method for preventing the voltage level of the detection control signal for line e to line g from changing even when the main key 12a is pressed, as described above, the output port is set to the input mode and pulled up. Thus, it is conceivable other than the method of keeping the voltage level of the detection amount control signal High regardless of whether the main key 12a is pressed or not.

  For example, without setting the pull-up resistor 103 of the output port, the output buffer 101 may be operated to set the output mode at the high voltage level. As a result, the search control signals for the lines a to d are in a high state, and the voltage levels of the detection control signals for the lines e to g are not changed regardless of whether the key switch is ON or OFF.

  Further, the key scan may be stopped by controlling the input port. A method for stopping such a key scan will be described by taking the key detection circuit of the side key 12b as an example.

  FIG. 5 is an example of a side key detection circuit that detects that one of the side keys 12b is pressed. An input port of the side key detection circuit is connected to one terminal of the side key switch 351 by a line h, and includes an output buffer 301, an input buffer 302, a pull-up resistor 303, and a transistor 304. The validity / invalidity of the pull-up resistor 303 is set by turning on / off the transistor 304. Further, the state can be switched between the state in which the input buffer 302 operates and the state in which the output buffer 301 operates.

  In this side key detection circuit, the detection control signal is normally set to High by enabling the pull-up resistor 303 and the input buffer is set to the input mode in which the input buffer is operated.

When the key switch 351 is pressed, the voltage level of the detection amount control signal changes to Low, so that it can be detected that the side key 12b is pressed.

  On the other hand, if the cellular phone 1 is key-locked, the user cannot enter the password using the numeric keypad of the main key 12a to release the key lock, even if the main key 12a or the side key 12b is pressed. The function assigned to the key does not operate by the key input. To release the key lock using the main key 12a, it is necessary to operate the numeric keypad. Therefore, when the main key 12a is covered by the upper casing or the like, the key of the main key 12a is invalidated. Sometimes the key lock cannot be released.

  Therefore, when it is detected that the key lock is set and the closed state or the folded state is detected, the pull-up resistor 303 of the input port is invalidated to set the voltage level of the line h to Low and output. The output mode in which the buffer 301 is operated is set.

  As described above, by switching the input port to the low signal output mode, the voltage level of the line h is low and does not change regardless of whether the key switch 351 is OFF or ON. For this reason, even if the side key 12b is pressed and the key switch 351 is turned on, it is possible to prevent a wasteful current from flowing through the line h.

  Next, still another method for controlling the input port to stop key detection will be described by taking a side key detection circuit as an example. FIG. 6 is an example of a side key detection circuit that detects that one of the side keys 12b is pressed. The input port of the side key detection circuit is connected to one terminal of the side key switch 351 by a line i, and includes an output buffer 301, an input buffer 302, a pull-up resistor 303, a transistor 304, a transistor 305, and a pull-down resistor 306. Is done. The validity / invalidity of the pull-up resistor 303 and the pull-down resistor 306 is set by ON / OFF of the transistor 304 and the transistor 305, respectively. Further, the state can be switched between the state in which the input buffer 302 operates and the state in which the output buffer 301 operates.

  In this side key detection circuit, normally, the pull-up resistor 303 is enabled to set the control signal for detection of line i to High, and the input buffer 302 is operated to set the input mode. When the side key switch 351 is turned on in this state, the voltage level of the detection amount control signal changes to Low, and by detecting this, it can be detected that the side key 12b is pressed.

  On the other hand, when it is detected that the key lock is set and the case is closed or folded, the pull-up resistor 303 is set to invalid while the input buffer 302 is operated, The pull-down resistor 306 is controlled to be effective. As a result, when the side key switch 351 is OFF, the voltage level of the line i becomes low.

  That is, the voltage level of the line i is low and does not change regardless of whether the side key switch 351 is OFF or ON. For this reason, it is possible to prevent a wasteful current from flowing through the line i even when the side key switch 351 is turned on.

  As described above, as described using the key detection circuit of the main key 12a and the key detection circuit of the side key 12b, the open / close state and the key lock state of the mobile phone are detected, and the key detection is stopped according to these states. Thus, when a key is pressed unintentionally by the user, it is possible to prevent unnecessary current consumption from occurring due to the key being pressed.

  Furthermore, as described above, the stop of key detection in accordance with the state of the mobile phone such as the open / close state and the key lock state can be set for each detection circuit. For example, when the mobile phone is closed when not in the key lock state, the key detection of the main key 12a is stopped, but the key detection of the side key 12b can be set not to be stopped. Thereby, even if the cellular phone is closed, the key exposed to the outside can be made effective. Further, for example, the power key 12c can be set to always perform key detection regardless of the state of the mobile phone. As a result, the power supply can only be turned on / off regardless of the state of the cellular phone.

  In the above embodiment, the folding-type mobile phone has been described as an example, but a mobile phone having another shape such as a slide type or a flap type may be used. For example, in the case of a mobile phone in which the key may be covered by opening and closing, the key detection circuit of the key detection circuit stops the key detection of the key when detecting the state where the key is covered. By controlling the input port and the output port, it is possible to prevent generation of useless current consumption. Further, if the mobile phone can set the key lock, detection of an auxiliary key that is not used for releasing the key lock may be stopped regardless of the opening / closing mechanism.

  In the above embodiment, the detection circuit is divided into a detection circuit for the main key 12a, a detection circuit for the side key 12b, and a detection circuit for the power key 12c. However, the present invention is not limited to this. The detection circuit may be further divided from detection circuits such as direction keys and function keys.

  In the above embodiment, the case where the key detection is stopped according to the open / close state or the key lock state has been described as an example. However, a case where another state is detected as a key detection stop condition may be added. .

  Thus, the present invention is not limited to the above-described embodiment, and may be changed as appropriate without departing from the gist of the present invention.

1 is an external view of an electronic device according to an embodiment of the present invention. 1 is an external view of an electronic device according to an embodiment of the present invention. The block diagram of the electronic device which concerns on embodiment of this invention. 1 is a diagram showing a main key detection circuit of an electronic device according to an embodiment of the present invention. 1 is a diagram showing a side key detection circuit of an electronic device according to an embodiment of the present invention. 1 is a diagram showing a side key detection circuit of an electronic device according to an embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mobile phone, 11 Display, 12a Main key, 12b Side key, 12c Power key, 2 Battery, 51 Control part, 52 Storage part, 53 Operation part, 54 Communication part, 55 Signal processing part, 56 Voice input / output part, 57 Display unit, 58 Power supply control unit

Claims (2)

Key,
A key switch provided corresponding to the key;
An upper housing provided with a display;
A lower housing provided with the key;
A first state in which the upper housing and the lower housing are folded and overlapped so that the display and the key face each other, and the back surface of the display and the back surface of the key face each other so that the key is exposed. A movable part capable of switching between a second state in which the upper housing and the lower housing are folded and stacked, and a third state in which the upper housing and the lower housing are not stacked;
State detecting means for detecting the first state, the second state, and the third state;
A key press detection means for detecting a state where the key is pressed and a state where the key is not pressed depending on whether the voltage level of the wiring connected to one end of the key switch is High or Low;
When the second state is detected by the state detection means, the voltage level of the wiring connected to one end of the key switch becomes the same High or Low, whether the key is pressed or not pressed. And an electronic device having control means for controlling the electronic device. An electronic device having a mechanism in which at least a part of the housing can be opened and closed,
A first key that is concealed when the housing is closed and exposed when the housing is open;
A second key exposed regardless of the open / closed state of the housing;
A first key switch corresponding to the first key;
A second key switch corresponding to the second key;
State detecting means for detecting an open / closed state of the housing;
A first state in which a state in which the first key is pressed and a state in which the first key is not pressed is detected based on whether the voltage level of the wiring connected to one end of the first key switch is High or Low. A key press detection means,
A second state in which a state in which the second key is pressed and a state in which the second key is not pressed is detected based on whether the voltage level of the wiring connected to one end of the second key switch is High or Low. A key press detection means,
Lock setting means for locking so that the functions assigned to the first key and the second key are not operated when the state detection means detects the closed state of the housing;
Unlocking means for releasing the lock state set by the lock setting means according to the operation of the first key when the state detection means detects the open state of the housing;
When the closed state is detected by the state detecting unit, the second key switch can be used regardless of whether the second key is pressed or not pressed when the locked state is set by the lock setting unit. an electronic apparatus, comprising a control means for controlling the voltage level of the connected wiring not changed to the same High or Low in.

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