KR20030017858A - Portable electronic device capable of reducing power consumption in waiting mode - Google Patents

Abstract

PURPOSE: A portable electronic device reducing power consumption in a waiting mode is provided to minimize the unnecessary power consumption at the waiting mode by making a communication oscillator not generate a clock signal. CONSTITUTION: At the operation mode, the communication oscillator(100) is switched to the waiting mode by responding to a control signal of the first state. At the waiting mode, the communication oscillator(100) is switched to the operation mode if the control signal of the second state is inputted. The communication interface(200) exchanges the signal with a host at the operation mode by responding to the clock signal. In case that a waiting mode command is inputted from the host, the communication interface(200) interrupts the communication with the host by being switched to the waiting mode. The communication interface(200) generates a setting signal expressing the operation and the waiting mode. At the operation mode, a power controller(300) generates the control signal of the first state by responding to the setting signal and is switched to the waiting mode. If a start bit is inputted at the waiting mode, the power controller(300) generates the control signal of the second state.

Description

PORTABLE ELECTRONIC DEVICE CAPABLE OF REDUCING POWER CONSUMPTION IN WAITING MODE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to portable electronic devices that communicate certain signals with a host, and more particularly, to portable electronic devices that reduce unnecessary power consumption in standby mode.

In general, a portable electronic device connected to a host is operated in response to a control signal provided from the host in an operation mode, and transmits a signal or data generated by the operation to the host. Since the available electronic power is limited, it is preferable that the portable electronic device is configured to have a standby mode to prevent excessive power consumption when not performing a specific operation.

The portable electronic device having the standby mode as described above includes a display device in the form of glasses connected to a hand-held computer, a mobile phone, a personal digital assistant (PDA), and a digital camera connected to the computer. In the present specification, in describing the above-described portable electronic device, for convenience of description, a digital camera currently commercially available will be described as an example.

The digital camera typically receives a camera control signal such as an image control command or a standby mode command from a host such as a mobile phone, a personal digital assistant (PDA) and a computer. In addition, the digital camera in the standby mode detects a start bit input from the host when a start bit indicating a start of a new operation is generated in the host. Here, when the image control command is input, the digital camera generates image data corresponding to the image of the subject or transmits the generated image data to the host. While maintaining a state capable of generating and transmitting image data (that is, an operation mode), the digital camera consumes a large amount of power even without generating or transmitting image data.

Accordingly, the digital camera has a standby mode that can prevent unnecessary power consumption, and switches from the operation mode to the standby mode in response to the standby mode command provided from the host. When the start bit is input from the host in the standby mode, the digital camera is reset to switch to the operation mode.

Next, a digital camera will be briefly described among portable electronic devices having a standby mode according to the prior art with reference to FIG. Referring to FIG. 1, a digital camera having a standby mode according to the related art is called a universal asynchronous receive transmitter interface (hereinafter referred to as a "UART interface"), which is a communication interface connected to the communication oscillation unit 10 and the host 1. 20, a power controller 30, and an image processor 40.

The communication oscillator 10 generates a clock signal CLK1 having a predetermined oscillation period, and provides the generated clock signal CLK1 to the UART interface 20 and the power controller 30.

The UART interface 20 converts the camera control signal RX input from the host 1 according to the UART protocol and then provides the power control unit 30 to provide the image signal TX to the host 1. do.

In the digital camera having the standby mode of the prior art configured as described above, in the standby mode, the communication oscillator 10 generates the clock signal CLK1 of a predetermined oscillation period, and the UART interface 20 and the power controller 30 ) And the image processor 40 maintain a standby state to minimize power consumption. In this case, the UART interface 20 and the power control unit 30 may communicate with each other by the clock signal CLK1 generated from the communication oscillator 10.

In this state, when the start bit is input from the host 1, the UART interface 20 outputs a setting signal UST1 and switches to the operation mode. At this time, the power control unit 200 receives the setting signal (USET1) to generate a control signal (POCON1). Then, the image processor 40 is switched to the operation mode in response to the control signal POCON1.

However, according to the portable electronic device having the standby mode of the related art as described above, the communication oscillator 10 continues to operate to generate the clock signal CLK1 even in the standby mode. Therefore, due to excessive power consumption in the communication oscillator 10, the conventional portable electronic device has a problem that the power consumption is large.

SUMMARY OF THE INVENTION The present invention has been made to effectively solve the above-mentioned problems of the prior art, and an object thereof is to provide a portable electronic device which reduces power consumption in a standby mode.

In order to more fully understand the drawings used in the detailed description of the invention, a brief description of each drawing is provided.

1 is a block diagram schematically illustrating a configuration of a digital camera controlled by a host as an example of a portable electronic device having a standby mode according to the prior art.

FIG. 2 is a block diagram illustrating a configuration of a portable electronic device that reduces power consumption in a standby mode according to an embodiment of the present invention, and shows a digital camera in the portable electronic device as a whole.

FIG. 3 is a block diagram showing an internal configuration of the power control unit shown in FIG.

4 is a timing diagram of main signals related to mode switching in a portable electronic device according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: communication oscillator 200: communication interface

300: power control unit 400: image processing unit

One aspect of the present invention for achieving the above technical problem is to transmit and receive a predetermined signal with the host, operating in the standby mode in response to the standby mode command provided from the host, in the standby mode, the input from the host The present invention relates to a portable electronic device which detects a start bit and switches to an operation mode. According to an aspect of the present invention, a portable electronic device generates a clock signal oscillated at a predetermined oscillation period in an operation mode, and stops generation of the clock signal in response to a control signal of a first state input from an external source. An oscillation means which is switched to a standby mode and, in the standby mode, switches to the operation mode when a control signal of a second state is input from the outside; In the operation mode, the signal is transmitted and received in response to the oscillating clock signal, and when the standby mode command is input from the host, the standby mode is switched to block transmission and reception of the signal with the host. Communication interfacing means comprising: said communication interfacing means for generating a setting signal indicative of said operating mode or said standby mode; And generating a control signal of the first state in response to the setting signal, switching to the standby mode, and generating the control signal of the second state when the start bit is input in the standby mode. And a power control means.

DETAILED DESCRIPTION In order to fully understand the present invention, its operational advantages, and the object attained by the practice of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents set forth in the accompanying drawings.

Hereinafter, a portable electronic device for reducing power consumption in a standby mode according to a preferred embodiment of the present invention will be described in detail with reference to FIGS. 2 to 4.

FIG. 2 is a block diagram illustrating a configuration of a portable electronic device that reduces power consumption in a standby mode according to an embodiment of the present invention, and shows a digital camera in the portable electronic device as a whole. 2, a digital camera according to an embodiment of the present invention includes a communication oscillator 100, a communication interface 200, a power controller 300, and an image processor 400.

The communication oscillator 100 generates a clock signal CLK2 that is oscillated at a predetermined oscillation period in an operation mode, and provides the generated clock signal CLK2 to the communication interface 200 and the power controller 300. The communication oscillator 100 may be switched to the standby mode in which generation of the clock signal CLK2 is stopped in response to the control signal POCON2 of the first state input from the power controller 300. When switching from the standby mode to the operation mode, the communication oscillator 100 generates the clock signal CLK2 again in response to the control signal POCON2 in the second state input from the power controller 300. The generated clock signal CLK2 is provided to the communication interface 200 and the power controller 300.

The communication interface 200 converts the camera control signal RX input from the host 1 according to a predetermined protocol while the communication oscillator 100 generates the clock signal CLK2, that is, in the operation mode. And outputs the video signal TX to the host 1. In addition, in the operation mode, the communication interface 200 generates a setting signal UST2 in a state of driving the communication oscillator 100 and the image processor 400 and provides it to the power control unit 300. In such an operation mode, when the standby mode command is input from the host 1, the setting signal UST2 provided to the power controller 300 is generated as a pulse, and the communication interface 200 is switched to the standby mode. At this time, the camera control signal RX input from the host 1 is in a "high" state. In addition, the communication interface 100 in the standby mode is reset by receiving a reset signal of the power control unit 300 to be described later. Preferably, the Universal Serial Asynchronous Receiver Transmitter (UART) interface (hereinafter, referred to as “UART”) in which the communication interface 200 converts and outputs a camera control signal RX input from the host 1 according to the UART protocol. Interface ".

When the setting signal UST2 provided from the UART interface 100 is generated as a pulse, the power control unit 300 generates the control signal POCON2 in the first state and switches to the standby mode. When the start bit is generated in the host 1 and the camera control signal RX in the "low" state is input, that is, the start bit is input, the power control unit 300 receives the control signal in the first state. POCON2) is transitioned to the second state. In this embodiment, the first state of the control signal POCON2 is a "high" state, and the second state is a "low" state.

In other words, when the setting signal UST2 is generated as a pulse, the power control unit 300 in the operation mode switches to the standby mode and transmits the control signal POCON2 in the "high" state to the communication oscillator 100 and the image processor 400. ) And monitor the camera control signal RX input from the host 1. In this state, when the start bit is input from the host 1, the power control unit 300 generates the control signal POCON2 in the "low" state. 3, the power control unit 300 includes a control register 310 and a reset detector 320.

The control register 310 transitions the control signal POCON2 to "high" when the setting signal UST2 provided from the UART interface 200 is generated as a pulse in the operation mode. When the start bit is input from the host 1 in the standby mode, the control register 310 transitions the control signal POCON2 to the "low" state.

The reset detection unit 320 in the standby mode receives a control signal POCON2 in a "low" state generated from the control register 310 and a clock signal CLK2 generated from the communication oscillator 100. The reset signal RESET is generated after a time delay of, and the generated reset signal RESET is provided to the UART interface 200. Here, the occurrence of the reset signal RESET after a predetermined time delay prevents the UART interface 200 and the image processing unit (ie, circuits inside the digital camera) 400 from operating in an unstable state. To do this.

The image processor 400 receives a control signal POCON2 in a "low" state from the power control unit 300 in an operation mode, and transmits the signal to a lens (not shown) according to a signal output from the UART interface 200. Image data corresponding to the image of the captured object is generated and output as the image signal TX. When the control signal POCON2 of the “high” state is input from the power controller 300, the image processor 400 is switched to the standby mode. The image processor 400 includes a sensor 410 for generating a detection signal corresponding to an image of a subject, a processor 420 for processing the detection signal, and an internal oscillator 430.

Mode switching of the digital camera for reducing power consumption in the standby mode of the present invention as described above is described as follows with reference to FIG. As shown in FIG. 4, first, when a standby mode command is input from the host 1, the UART interface 200 generates a setting signal UST2 as a pulse and switches to the standby mode. At this time, the reset register 310 of the power control unit which has received the setting signal UST2 generated as a pulse transitions the control signal POCON2 to "high" and switches to the standby mode. The power control unit 300 switched to the standby mode monitors the camera control signal RX during the standby mode in order to detect a start bit input from the host 1.

In addition, the communication oscillator 100 receiving the control signal POCON2 in the "high" state stops the generation of the clock signal CLK2, is switched to the standby mode, and the image processor 400 is also switched to the standby mode. . Accordingly, in the standby mode, the UART interface 200 and the power control unit 300 cannot communicate with each other. As described above, in the standby mode, since the communication oscillator 100 stops the generation of the clock signal CLK2, the power consumption may be significantly reduced.

Then, when the start bit is generated in the host 1 and the camera control signal RX of the "low" state is input, the reset register 310 of the power control unit detects the start bit and the control signal POCON2. ) Transitions to the "low" state. At this time, the image processing unit 400 is switched to the operation mode to generate and output the image data of the subject according to the image control signal input through the UART interface 200. The communication oscillator 100 generates a clock signal CLK2 in response to the control signal POCON2 in a "low" state, and resets the generated clock signal CLK2 of the UART interface 200 and the power controller. It is provided to the sensing unit 320.

In this case, the reset detector 320 generates a reset signal RESET after a predetermined time delay and provides the reset signal RESET to the UART interface 200. Then, the UART interface 200 is reset in response to the reset signal RESET. Subsequently, the UART interface 200 converts and outputs an image control command provided from the host 1 according to the UART protocol. In this case, the image processor 400 generates a detection signal for an image of a subject captured by the sensor 410 in response to an image control command of the host 1 output from the UART interface 20. 420 processes the detection signal. Here, the sensor 410 and the processor 420 communicate with each other by the internal oscillator 430.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. For example, in the above-described embodiment, the portable electronic device having the standby mode is illustrated and described with respect to the digital camera including the image processing unit 400. However, the present invention is not limited thereto. The present invention can be applied to any portable communication device having a standby mode in communication with a predetermined host, such as a portable display device capable of displaying an operation state of the device. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

According to the portable electronic device for reducing power consumption in the standby mode described above, in the standby mode, since the communication oscillator does not generate the clock signal, unnecessary power consumption can be minimized.

In addition, in the portable electronic device of the present invention, when switching from the standby mode to the operation mode, the communication interface is reset, so that the communication interface can be more reliable than the prior art.

Claims (3)

A portable electronic device that transmits and receives a predetermined signal with a host and operates in a standby mode in response to a standby mode command provided from the host. In In the operation mode, a clock signal that is oscillated at a predetermined oscillation period is generated, and is switched to the standby mode that stops generation of the clock signal in response to a control signal of a first state input from the outside, and in the standby mode Oscillating means for switching to the operation mode when a control signal of a second state is input from the outside; In the operation mode, the signal is transmitted and received with the host in response to the oscillated clock signal, when the standby mode command is input from the host, the standby mode is switched to block the transmission and reception of the host and the signal Communication interfacing means comprising: said communication interfacing means for generating a setting signal indicative of said operating mode or said standby mode; And In the operation mode, the control signal of the first state is generated in response to the setting signal, and is switched to the standby mode, and when the start bit is input in the standby mode, the control signal of the second state is generated. Power control means Portable electronic device comprising a. The method of claim 1, wherein the power control means And when the start bit is input in the standby mode, after a delay of a predetermined time, generating a reset signal for resetting the interfacing means. The method of claim 2, wherein the power control means A reset register generating a control signal of the second state when the start bit is input from the host in the standby mode; And The reset detector is enabled by the control signal in the second state and generates the reset signal in response to the oscillating clock signal. Portable electronic device comprising a.