Imaging device

Abstract

To provide an imaging device that operates stably. [Solution] An imaging device (100) operates by consuming power based on a battery voltage output from a battery (162). The imaging device (100) includes a first voltage generating unit (2a), a first load (3), a supply line (7), a second voltage generating unit (2b), and an output unit (4). The first voltage generating unit (2a) generates an output voltage from an input voltage. The first load (3) is supplied with a first power based on the output voltage of the first voltage generating unit (2a). The supply line (7) supplies a second power to a second load (8) based on the battery voltage. The second voltage generating unit (2b) generates a set voltage (VS) from the battery voltage. The output unit (4) supplies the higher voltage, either the set voltage (VS) or a variable voltage that drops when the second power is supplied to the second load (8), as an input voltage to the first voltage generating unit (2a).

Description

[Technical Field]

[0001] The present disclosure relates to an imaging device. [Background technology]

[0002] Patent Document 1 discloses an electronic device having multiple operating modes. The electronic device of Patent Document 1 includes a power input terminal, a power supply unit such as a DC / DC converter, a first load, a second load, a first switch circuit, a second switch circuit, and a control circuit. The power supply unit converts power input from the power input terminal into a predetermined power. The first switch circuit is provided on a first power supply line that supplies power from the power supply unit to the first load. The second switch circuit is provided on a second power supply line that supplies power to the second load. The second power supply line branches off from the first power supply line. More specifically, the second power supply line branches off from the input side of the first switch circuit. The control circuit controls the first switch circuit and the second switch circuit. For example, in a first operating mode, the control circuit turns on each of the first switch circuit and the second switch circuit to supply power to the first load and the second load. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-69666 Summary of the Invention [Problem to be solved by the invention]

[0004] However, multiple power supply units may be connected in parallel to a power input terminal. In this configuration, if the current output from one power supply unit suddenly increases, the input voltage to the other power supply units may drop, causing the other power supply units to stop operating. This makes it impossible to operate the electronic device stably.

[0005] An object of the present disclosure is to provide an imaging device that operates stably. [Means for solving the problem]

[0006] An imaging device according to one aspect of the present disclosure operates by consuming power based on a battery voltage output from a battery. The imaging device includes a first voltage generation unit, a first load, a supply line, a second voltage generation unit, and an output unit. The first voltage generation unit generates an output voltage from an input voltage. The first load is supplied with a first power based on the output voltage. The supply line supplies a second load with a second power based on the battery voltage. The second voltage generation unit generates a set voltage from the battery voltage. The output unit supplies the higher voltage, either the set voltage or a variable voltage that drops when the second power is supplied to the second load, as the input voltage to the first voltage generation unit. [Effects of the Invention]

[0007] According to the imaging device of the present disclosure, the imaging device can be operated stably. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram illustrating a configuration of a digital camera according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a block diagram showing the configuration of a voltage generating unit included in a digital camera according to an embodiment of the present disclosure. [Figure 3] 3 is a graph showing voltage values ​​at points a, b, c, and d in FIG. 2. FIG. [Figure 4] 2 is a circuit diagram schematically illustrating the configuration of a switched capacitor, a first output section, and a second output section included in a digital camera according to an embodiment of the present disclosure. FIG. [Figure 5] 10 is a diagram showing the relationship between the operation modes of the digital camera and two states of the second output section according to an embodiment of the present disclosure. FIG. [Figure 6]FIG. 10 is a circuit diagram schematically illustrating a configuration of a modified example of an output unit included in a digital camera according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of an imaging device according to the present disclosure will be described with reference to the drawings. However, the present disclosure is not limited to the following embodiments, and can be implemented in various forms without departing from the spirit of the present disclosure. Note that duplicated explanations may be omitted as appropriate. In addition, the same reference symbols are used for the same or equivalent parts in the drawings, and explanations will not be repeated.

[0010] The configuration and operation of a digital camera with interchangeable lenses as an example of an imaging device according to an embodiment of the present disclosure will be described below.

[0011] 1. About digital cameras Fig. 1 is a block diagram showing the configuration of a digital camera 100 according to this embodiment. As shown in Fig. 1, the digital camera 100 includes an interchangeable lens 101 and a camera body 150. The camera body 150 has an internal battery 162. The digital camera 100 operates based on the battery voltage output from the internal battery 162. More specifically, the digital camera 100 operates by consuming power based on the battery voltage.

[0012] 1-1. Interchangeable lenses The interchangeable lens 101 is detachably attached to the camera body 150. The interchangeable lens 101 forms an image of light incident on the interchangeable lens 101 on a CMOS image sensor 154 of the camera body 150, which will be described later. As a result, a subject image is formed on the CMOS image sensor 154. Specifically, the interchangeable lens 101 has an optical system 102, a drive unit 103, a lens controller 104, a flash memory 105, a lens mount 106, a gyro sensor 107, and a position sensor 108.

[0013] The optical system 102 includes multiple lenses arranged along an optical axis AX. The optical system 102 forms an image of light incident on the interchangeable lens 101 via the multiple lenses on a CMOS image sensor 154 of the camera body 150, which will be described later.

[0014] In this embodiment, the optical system 102 includes a zoom lens 121, an OIS (Optical Image Stabilizer) lens 122, and a focus lens 123.

[0015] The zoom lens 121 is driven by the driving unit 103 to change the magnification of the subject image formed on the CMOS image sensor 154 .

[0016] OIS lens 122 is driven by drive unit 103 to correct blurring of the subject image formed on CMOS image sensor 154. Blurring of the subject image occurs when digital camera 100 is displaced due to camera shake, for example, during image capture.

[0017] The focus lens 123 is driven by the drive unit 103 to change the focus state of the subject image formed on the CMOS image sensor 154 .

[0018] The driving unit 103 drives some or all of the multiple lenses included in the optical system 102. For example, the driving unit 103 drives some of the multiple lenses included in the optical system 102 to change the magnification of the subject image formed on the CMOS image sensor 154. The driving unit 103 also drives another part of the multiple lenses included in the optical system 102 to change the focus state of the subject image formed on the CMOS image sensor 154. The driving unit 103 also drives yet another part of the multiple lenses included in the optical system 102 to correct blurring of the subject image formed on the CMOS image sensor 154.

[0019] In this embodiment, the driving unit 103 includes a zoom lens driving unit 131 , an OIS driving unit 132 , and a focus lens driving unit 133 .

[0020] The zoom lens driving unit 131 drives the zoom lens 121. The zoom lens driving unit 131 may include an actuator that drives the zoom lens 121. The actuator may include, for example, a motor such as a DC motor, a stepping motor, a servo motor, or an ultrasonic motor, and a motor driver that drives the motor.

[0021] The OIS driver 132 drives the OIS lens 122. The OIS driver 132 may include an actuator that drives the OIS lens 122. The actuator may include, for example, a magnet and a flat coil.

[0022] Focus lens driving unit 133 drives focus lens 123. Focus lens driving unit 133 may include an actuator that drives focus lens 123. The actuator may include, for example, a motor such as a DC motor, a stepping motor, a servo motor, or an ultrasonic motor, and a motor driver that drives the motor.

[0023] The gyro sensor 107 detects shake (vibration) in the yawing direction and pitching direction based on the angular velocity of the digital camera 100. The angular velocity indicates the angular change per unit time of the digital camera 100. The gyro sensor 107 outputs an angular velocity signal indicating the amount of detected shake (angular velocity) to the lens controller 104. Note that instead of the gyro sensor 107, another sensor capable of detecting shake of the digital camera 100 can also be used.

[0024] The position sensor 108 detects the position of the OIS lens 122 in a plane perpendicular to the optical axis AX. The position sensor 108 outputs a signal indicating the detected position of the OIS lens 122 to the lens controller 104. The position sensor 108 may include, for example, a magnet and a Hall element.

[0025] The lens controller 104 controls the drive unit 103 to drive some or all of the lenses included in the optical system 102. In this embodiment, the lens controller 104 controls a zoom lens drive unit 131, an OIS drive unit 132, and a focus lens drive unit 133.

[0026] More specifically, the lens controller 104 controls the zoom lens driving unit 131 to change the magnification of the subject image formed on the CMOS image sensor 154 .

[0027] Furthermore, the lens controller 104 controls the focus lens driving unit 133 to change the focus state of the subject image formed on the CMOS image sensor 154 .

[0028] Furthermore, the lens controller 104 corrects blurring of the subject image formed on the CMOS image sensor 154 by controlling the OIS driver 132 based on the output of the gyro sensor 107 and the output of the position sensor 108 .

[0029] The lens controller 104 may include, for example, a hardwired electronic circuit. Alternatively, the lens controller 104 may include a processor that executes a computer program, or may include a processor and a hardwired electronic circuit. For example, the lens controller 104 may include a CPU (Central Processing Unit) as the processor.

[0030] The lens controller 104 may further include a memory. The memory may be a semiconductor memory. For example, the lens controller 104 may include at least one of a ROM (Read Only Memory) and a RAM (Random Access Memory) as the semiconductor memory. The lens controller 104 may be an MCU (Micro Controller Unit) or an SoC (System On a Chip).

[0031] The flash memory 105 stores lens data. The lens data includes characteristic values ​​of the interchangeable lens 101, such as the lens name, lens ID, lens model, serial number, F-number, and focal length. The flash memory 105 may also store computer programs and parameters used by the lens controller 104 when controlling the driving unit 103. In this case, the lens controller 104 controls the driving unit 103 based on the computer programs and parameters stored in the flash memory 105. Note that if the lens controller 104 has a memory, all or part of the computer programs and parameters used by the lens controller 104 when controlling the driving unit 103 may be stored in the memory of the lens controller 104.

[0032] The lens mount 106 is detachably connected to a body mount 151 of the camera body 150, which will be described later. More specifically, the lens mount 106 is mechanically and electrically connected to the body mount 151 of the camera body 150.

[0033] 1-2. Camera body configuration Next, the camera body 150 will be described. As shown in Fig. 1, the camera body 150 further includes, in addition to an internal battery 162, a body mount 151, a mechanical shutter 152, a mechanical shutter drive unit 153, a CMOS image sensor 154, a release button 155a, a mode switching dial 155b, a power switch 155c, an operation unit 156, a monitor 157, a card slot 158, an HDMI (registered trademark) terminal 159, a camera controller 160, a flash memory 161, and a voltage generation unit 2. The internal battery 162 is attached inside the camera body 150. The internal battery 162 may be detachably attached to the camera body 150. The internal battery 162 is an example of a "battery."

[0034] Mechanical shutter 152 is disposed between optical system 102 of interchangeable lens 101 and CMOS image sensor 154, and adjusts the exposure time of light incident on CMOS image sensor 154 from optical system 102. Mechanical shutter drive unit 153 drives mechanical shutter 152. Mechanical shutter drive unit 153 includes an actuator that drives mechanical shutter 152. The actuator includes a motor such as a DC motor or a stepping motor, and a motor driver that drives the motor. Mechanical shutter drive unit 153 is controlled by camera controller 160. Camera controller 160 controls mechanical shutter drive unit 153 to adjust the exposure time.

[0035] As already explained, the optical system 102 of the interchangeable lens 101 forms an image of light incident on the interchangeable lens 101 on the CMOS image sensor 154. As a result, a subject image is formed on the CMOS image sensor 154. The CMOS image sensor 154 outputs a digital signal indicating the subject image to the camera controller 160.

[0036] The camera controller 160 performs predetermined image processing on the digital signal representing the subject image output from the CMOS image sensor 154. The predetermined image processing includes, for example, gamma correction processing, white balance correction processing, blemish correction processing, YC conversion processing, digital zoom processing, compression processing, and expansion processing. However, the predetermined image processing is not limited to these processes. Hereinafter, the digital signal representing the subject image that has undergone predetermined image processing may be referred to as "image data."

[0037] The image data includes image data of still images, image data of moving images, and image data of through images. Specifically, the camera controller 160 controls the operation of the CMOS image sensor 154 to selectively generate image data of still images, image data of moving images, and image data of through images. Note that the through images are mainly moving images.

[0038] Release button 155a is provided on the exterior of camera body 150. Release button 155a accepts a user's operation to issue an image capture command or an autofocus command. Specifically, release button 155a can be operated in two stages: halfway down and fully down. When the user halfway down the release button 155a, camera controller 160 controls focus lens driver 133 via lens controller 104 to cause focus lens driver 133 to perform an autofocus operation. When the user fully down the release button 155a, camera controller 160 records image data of a still image generated in accordance with the timing of the full down operation on memory card MC or flash memory 161.

[0039] Mode switching dial 155b is provided on the exterior of camera body 150. Mode switching dial 155b accepts an operation by the user to instruct switching of the operation mode. The operation to instruct switching of the operation mode includes an operation to switch the operation mode of digital camera 100 between still image shooting mode and video shooting mode. When mode switching dial 155b accepts an operation to switch the operation mode of digital camera 100 from still image shooting mode to video shooting mode, camera controller 160 switches the operation mode of digital camera 100 from still image shooting mode to video shooting mode. Similarly, when mode switching dial 155b accepts an operation to switch the operation mode of digital camera 100 from video shooting mode to still image shooting mode, camera controller 160 switches the operation mode of digital camera 100 from video shooting mode to still image shooting mode.

[0040] The power switch 155c is provided on the exterior of the camera body 150. The power switch 155c accepts a power on / off operation by the user. When the power switch 155c accepts a power on operation, the camera controller 160 controls the voltage generation unit 2 to start supplying power to each unit (each load) of the camera body 150 and the interchangeable lens 101. When the power switch 155c accepts a power off operation, the camera controller 160 controls the voltage generation unit 2 to stop supplying power to each unit (each load) of the camera body 150 and the interchangeable lens 101.

[0041] Operation unit 156 accepts operations by the user and outputs operation signals corresponding to the operations to camera controller 160. Operation unit 156 includes hard keys such as operation buttons and operation levers provided on the exterior of digital camera 100. Operation unit 156 may further include a touch panel superimposed on monitor 157.

[0042] The operation unit 156 includes, for example, a cross button. For example, when an interchangeable lens 101 with an electric zoom function is attached to the camera body 150, the camera controller 160 assigns the function of zoom operation buttons to the left and right buttons included in the cross button.

[0043] Monitor 157 is a display unit disposed on the rear surface of camera body 150. Monitor 157 includes a display such as a liquid crystal display or an organic EL (Electro-Luminescence) display.

[0044] Monitor 157 is controlled by camera controller 160 to display a screen for notifying the user of information such as the settings of digital camera 100. Furthermore, monitor 157 is controlled by camera controller 160 to selectively display moving images and still images. For example, camera controller 160 reads image data from memory card MC or flash memory 161 in response to a user's operation of operation unit 156, and causes monitor 157 to display still images or moving images.

[0045] A memory card MC is removably inserted into the card slot 158. The card slot 158 ​​is electrically and mechanically connected to the inserted memory card MC. The card slot 158 ​​may have a function for controlling the memory card MC.

[0046] The memory card MC is an external memory that includes a storage element such as a flash memory, etc. The camera controller 160 may store image data in the storage element inside the memory card MC.

[0047] One end of an HDMI (registered trademark) cable is detachably connected to the HDMI (registered trademark) terminal 159. The other end of the HDMI (registered trademark) cable is connected to an external display device. The camera controller 160 outputs image data read from the memory card MC or the flash memory 161 to the HDMI (registered trademark) terminal 159. As a result, the still images or moving images recorded on the memory card MC or the flash memory 161 are displayed on the external display device.

[0048] The lens mount 106 of the interchangeable lens 101 is detachably connected to the body mount 151. More specifically, the body mount 151 is mechanically and electrically connected to the lens mount 106. The camera controller 160 and the lens controller 104 transmit and receive data to each other via the body mount 151 and the lens mount 106. For example, the lens controller 104 reads lens data from the flash memory 105 and outputs the lens data to the camera controller 160 via the lens mount 106 and the body mount 151. The camera controller 160 stores the lens data in the flash memory 161 or a memory inside the camera controller 160, and performs various controls by referring to the lens data.

[0049] Camera controller 160 may include, for example, a hardwired electronic circuit. Alternatively, camera controller 160 may include a processor that executes a computer program, or may include a processor and a hardwired electronic circuit. For example, camera controller 160 may include a CPU as a processor. Camera controller 160 may further include a GPU (Graphics Processing Unit).

[0050] The camera controller 160 may further include a memory. The memory may be a semiconductor memory. For example, the camera controller 160 may include at least one of a ROM and a RAM as the semiconductor memory. The camera controller 160 may be an MCU or an SoC.

[0051] The camera controller 160 controls the overall operation of the digital camera 100 by controlling each part of the digital camera 100 such as the CMOS image sensor 154 in response to signals from operation members such as the release button 155a and the operation unit 156.

[0052] For example, camera controller 160 outputs various control signals to lens controller 104 via body mount 151 and lens mount 106. For example, camera controller 160 generates a focus control signal in response to a half-press of release button 155a. The focus control signal is output to lens controller 104 via body mount 151 and lens mount 106. Lens controller 104 causes focus lens driver 133 to perform an autofocus operation based on the focus control signal.

[0053] Flash memory 161 stores computer programs and parameters used by camera controller 160 when controlling each part of digital camera 100. Camera controller 160 controls each part of digital camera 100 based on the computer programs and parameters stored in flash memory 161. If camera controller 160 has a memory, all or part of the computer programs and parameters used by camera controller 160 when controlling each part of digital camera 100 may be stored in the memory of camera controller 160.

[0054] The flash memory 161 may function as an internal memory for storing image data. Whether the image data is to be stored in the flash memory 161 or in the memory card MC may be determined by the user operating the operation unit 156.

[0055] The internal battery 162 supplies the battery voltage for driving the digital camera 100 to the voltage generation unit 2. The internal battery 162 may be, for example, a dry cell or a rechargeable battery. The voltage generation unit 2 generates drive voltages appropriate for each section (each load) of the digital camera 100 based on the battery voltage supplied from the internal battery 162. The drive voltages generated by the voltage generation unit 2 are then supplied to each section (each load) of the digital camera 100. As a result, power is supplied to each section (each load) of the digital camera 100. Note that a portion of the drive voltage generated by the voltage generation unit 2 is supplied to each section (such as the lens controller 104 and the drive unit 103) of the interchangeable lens 101 via the body mount 151 and the lens mount 106.

[0056] The voltage generation unit 2 may include a voltage detection circuit that detects the battery voltage. The battery voltage indicates a voltage value corresponding to the remaining capacity of the internal battery 162. The voltage detection circuit generates a detection signal indicating the detected value of the battery voltage and outputs it to the camera controller 160. The camera controller 160 determines whether the battery voltage is below an undercut voltage based on the detection signal. The undercut voltage is a lower limit value set for the battery voltage. If the camera controller 160 determines that the battery voltage is below the undercut voltage, it controls the voltage generation unit 2 to stop the supply of power (driving voltage) to each component (each load) of the camera body 150 and the interchangeable lens 101. In other words, the camera controller 160 turns off the power supply to the digital camera 100. Specifically, as the remaining capacity of the internal battery 162 decreases, the voltage value of the battery voltage decreases. Therefore, when the capacity of the internal battery 162 is consumed by operating the digital camera 100, the voltage value of the battery voltage decreases. As a result, the battery voltage falls below the undercut voltage, and the camera controller 160 turns off the power to the digital camera 100 .

[0057] 1-3. Voltage generation section Next, the voltage generating unit 2 of the digital camera 100 of this embodiment will be described in detail with reference to Fig. 2. Fig. 2 is a block diagram showing the configuration of the voltage generating unit 2 included in the digital camera 100 of this embodiment. As shown in Fig. 2, the voltage generating unit 2 includes a first voltage generating unit 2a, an output unit 4, a first supply line 5, a second supply line 6, a third supply line 7, and a fourth supply line 9.

[0058] The first voltage generating unit 2a generates an output voltage from an input voltage and supplies the output voltage to the first load 3. Specifically, a first power based on the output voltage of the first voltage generating unit 2a is supplied to the first load 3. The first load 3 operates based on the first power. Specifically, the first load 3 operates by consuming the first power.

[0059] In this embodiment, the first voltage generation unit 2a includes four voltage generation units 21a to 21d. The first load 3 includes the camera controller 160, the flash memory 161, and the CMOS image sensor 154 described with reference to FIG. 1. The voltage generation units 21a and 21b each supply a first power to the camera controller 160. The voltage generation units 21c and 21d each supply a first power to the flash memory 161 and the CMOS image sensor 154.

[0060] Specifically, the voltage generating units 21a to 21d are each a step-down DC / DC converter that steps down an input voltage to a predetermined voltage and outputs it. A lower limit VL is set for the input voltage in the voltage generating units 21a to 21d. When the voltage value of the input voltage falls below the lower limit VL, the voltage generating units 21a to 21d stop operating. Note that, hereinafter, the lower limit VL set for the input voltage of the first voltage generating unit 2a may be referred to as the "lower limit VL of the first voltage generating unit 2a" or the "lower limit VL."

[0061] The first supply line 5 supplies a first voltage to the output unit 4 based on the battery voltage of the internal battery 162. The first voltage is an example of a "variable voltage." In this embodiment, the first supply line 5 includes a switched capacitor 51. The switched capacitor 51 is an example of a step-down circuit that steps down the battery voltage to generate the first voltage. Specifically, the switched capacitor 51 generates a voltage that is 1 / n times the battery voltage. In this embodiment, the switched capacitor 51 generates a voltage that is 1 / 2 times the battery voltage.

[0062] The second supply line 6 includes a second voltage generator 2b. The second voltage generator 2b generates a set voltage VS from the battery voltage of the internal battery 162. The set voltage VS indicates a constant voltage value. Specifically, the second voltage generator 2b is a step-down DC / DC converter that steps down the battery voltage to the set voltage VS and outputs it. The set voltage VS indicates a voltage value greater than the lower limit value VL of the first voltage generator 2a described above.

[0063] The second supply line 6 supplies the set voltage VS output from the second voltage generating unit 2b as the second voltage to the output unit 4. The output unit 4 supplies the first voltage (half the battery voltage) supplied from the first supply line 5 or the second voltage (set voltage VS) supplied from the second supply line 6, whichever has a higher voltage value, as the input voltage to the first voltage generating unit 2a. Specifically, the voltage output from the output unit 4 is supplied as the input voltage to each of the voltage generating units 21a to 21d included in the first voltage generating unit 2a.

[0064] The third supply line 7 supplies the second power to the second load 8 based on the battery voltage of the internal battery 162. Specifically, the third supply line 7 includes a third voltage generator 2c. The third voltage generator 2c includes a step-down DC / DC converter and steps down the battery voltage of the internal battery 162 and supplies the stepped-down battery voltage to the second load 8. The third voltage generator 2c may also include a step-up DC / DC converter or a step-up / step-down DC / DC converter. More specifically, the third voltage generator 2c includes a DC / DC converter selected from a step-down DC / DC converter, a step-up DC / DC converter, and a step-up / step-down DC / DC converter based on the battery voltage and the drive voltage of the second load 8.

[0065] The second load 8 operates based on the second power supplied from the third supply line 7. More specifically, the second load 8 operates by consuming the second power. When the second power is supplied from the third supply line 7 to the second load 8, the battery voltage drops. As a result, when the second power is supplied to the second load 8, the first voltage (fluctuation voltage) supplied from the first supply line 5 to the output unit 4 drops. In this embodiment, the voltage (fluctuation voltage) output from the switched capacitor 51 drops.

[0066] Specifically, second load 8 includes mechanical shutter drive unit 153 described with reference to FIG. 1. More specifically, second load 8 includes an actuator of mechanical shutter drive unit 153. As already described, the actuator of mechanical shutter drive unit 153 includes a motor and a motor driver. When mechanical shutter drive unit 153 drives mechanical shutter 152, a relatively large drive current is supplied from the motor driver to the motor. As a result, when mechanical shutter 152 operates, the battery voltage drops, and the voltage (first voltage) output from switched capacitor 51 drops. More specifically, the battery voltage fluctuates sharply when mechanical shutter 152 operates.

[0067] The fourth supply line 9 branches off from the second supply line 6. The fourth supply line 9 supplies a third power based on the set voltage VS output from the second voltage generating unit 2b to a third load 91. The third load 91 operates based on the third power. More specifically, the third load 91 operates by consuming the third power.

[0068] In this embodiment, the third load 91 includes the monitor 157 and memory card MC described with reference to FIG. 1. The memory card MC is supplied with third power via a card slot 158. Furthermore, in this embodiment, the fourth supply line 9 supplies the third power to the camera controller 160. Therefore, the camera controller 160 is the first load 3 and also the third load 91.

[0069] Next, the digital camera 100 of this embodiment will be further described with reference to Fig. 2. As shown in Fig. 2, the voltage generation unit 2 further includes a fourth voltage generation unit 2d. The fourth voltage generation unit 2d generates a predetermined voltage from the battery voltage of the internal battery 162, and supplies the predetermined voltage to the HDMI (registered trademark) terminal 159 described with reference to Fig. 1. Specifically, the fourth voltage generation unit 2d includes a step-down DC / DC converter, and steps down the battery voltage to generate a voltage that complies with the HDMI standard.

[0070] 1-4. Output section Next, the output section of the digital camera 100 of this embodiment will be described with reference to Fig. 2. As shown in Fig. 2, in this embodiment, the output section 4 includes a first output section 41 and a second output section 42. In this embodiment, the first output section 41 and the second output section 42 form a diode OR circuit.

[0071] Specifically, the first output unit 41 outputs the first voltage when the first voltage (half the battery voltage) output from the switched capacitor 51 is equal to or greater than the second voltage (set voltage VS) output from the second voltage generating unit 2b. The second output unit 42 outputs the second voltage when the second voltage is equal to or greater than the first voltage. Therefore, when the first voltage is equal to or greater than the second voltage, the output unit 4 supplies the first voltage (half the battery voltage) as an input voltage to the first voltage generating unit 2a. Furthermore, when the second voltage is equal to or greater than the first voltage, the output unit 4 supplies the second voltage (set voltage VS) as an input voltage to the first voltage generating unit 2a.

[0072] In this embodiment, when the second voltage (set voltage VS) is equal to or greater than the voltage value of the first voltage (half the battery voltage), the first output unit 41 prevents a current based on the second voltage from flowing backward from the second output unit 42 to the first output unit 41. Similarly, when the first voltage is equal to or greater than the voltage value of the second voltage, the second output unit 42 prevents a current based on the first voltage from flowing backward from the first output unit 41 to the second output unit 42.

[0073] Next, digital camera 100 of this embodiment will be described with reference to FIGS. 2 and 3. FIG. 3 is a diagram showing graphs of voltage values ​​at points a, b, c, and d in FIG. 2. In each of the four graphs, the vertical axis represents voltage value V, and the horizontal axis represents time t. Time t1 represents the time when mechanical shutter drive unit 153 drives mechanical shutter 152. Voltages Va, Vb, Vc, and Vd represent voltages at points a, b, c, and d, respectively. More specifically, voltage Va represents the battery voltage. Voltage Vb represents the first voltage output from switched capacitor 51. Voltage Vc represents the second voltage (set voltage VS) output from second voltage generation unit 2b. Voltage Vd represents the voltage output from output unit 4. In other words, voltage Vd represents the input voltage supplied to first voltage generation unit 2a.

[0074] 3, at time t1, when mechanical shutter drive unit 153 drives mechanical shutter 152, the battery voltage (voltage Va) drops sharply. Therefore, at time t1, the first voltage (voltage Vb) output from switched capacitor 51 also drops sharply. As a result, at time t1, the first voltage (voltage Vb) becomes a voltage value less than lower limit VL of first voltage generation unit 2a.

[0075] On the other hand, the set voltage VS (voltage Vc) maintains a constant value even when the battery voltage (voltage Va) fluctuates. The output unit 4 supplies the first voltage generator 2a with the higher voltage between the first voltage (voltage Vb) and the set voltage VS (voltage Vc). Therefore, the output unit 4 outputs the first voltage (voltage Vb) (voltage Vd) during a period when the first voltage (voltage Vb) is equal to or greater than the set voltage VS (voltage Vc). The output unit 4 also outputs the set voltage VS (voltage Vd) during a period when the first voltage (voltage Vb) is less than the set voltage VS (voltage Vc). Therefore, even if the first voltage (voltage Vb) becomes less than the lower limit VL at time t1, the input voltage supplied to the first voltage generator 2a can be maintained at a voltage equal to or greater than the lower limit VL.

[0076] As described above with reference to FIGS. 1 to 3, according to this embodiment, even if the battery voltage (voltage Va) drops due to the supply of power to mechanical shutter drive unit 153 (second load 8), the input voltage to first voltage generation unit 2a does not become a voltage value below lower limit VL. As a result, the occurrence of a malfunction in which the operation of first voltage generation unit 2a stops due to the supply of power to mechanical shutter drive unit 153 (second load 8) is suppressed. Therefore, according to this embodiment, digital camera 100 can be operated stably.

[0077] Furthermore, in order to avoid the occurrence of the above-mentioned problems in a configuration in which the input voltage is supplied to the first voltage generating unit 2a only from the first supply line 5, it is necessary to set the undercut voltage high. In contrast, according to this embodiment, the occurrence of the above-mentioned problems can be suppressed without setting the undercut voltage high. Therefore, since the undercut voltage can be set low, the frequency of replacement or charging of the internal battery 162 can be reduced.

[0078] 1-5. Circuit configuration of output section etc. Next, the circuit configuration of the output section and the like of the digital camera 100 of this embodiment will be described with reference to Fig. 4. Fig. 4 is a circuit diagram that schematically shows the configurations of the switched capacitor 51, first output section 41, and second output section 42 included in the digital camera 100 of this embodiment.

[0079] 4, the switched capacitor 51 may include an input-side capacitor 11, an output-side capacitor 12, four Nch-type MOSFETs 13 to 16, a flying capacitor 17, and a controller 18. In this case, the input-side capacitor 11 is provided on the input side of the switched capacitor 51. A battery voltage is input to the input-side capacitor 11 from an internal battery 162. The output-side capacitor 12 is provided on the output side of the switched capacitor 51. The controller 18 controls the ON and OFF of the four Nch-type MOSFETs 13 to 16 so that the flying capacitor 17 and the output-side capacitor 12 are connected in series and the voltage of the output-side capacitor 12 is half the voltage of the input-side capacitor 11 (battery voltage).

[0080] As shown in FIG. 4, each of the Nch-type MOSFETs 13 to 16 has a parasitic diode, but the switched capacitor 51 may further have four diode elements connected in parallel to each of the Nch-type MOSFETs 13 to 16.

[0081] In this embodiment, as shown in FIG. 4 , the first output unit 41 includes a first ideal diode circuit 41a. By using the first ideal diode circuit 41a, the forward voltage can be brought closer to 0 V compared to a configuration using a diode element. This reduces the power consumed by the first output unit 41, thereby reducing the power consumption of the digital camera 100. This reduces the rate at which the remaining capacity of the internal battery 162 is consumed, thereby reducing the frequency of replacing or charging the internal battery 162. Furthermore, by using the first ideal diode circuit 41a, it is possible to prevent a current based on the second voltage from flowing back from the second output unit 42 to the first output unit 41 when the second voltage (set voltage VS) is equal to or higher than the first voltage (half the battery voltage).

[0082] Specifically, the first ideal diode circuit 41a may include two Nch-type MOSFETs 31 and 32, a comparator 33, a first controller , and a second controller .

[0083] 4, an Nch MOSFET 31 is provided on the input side of a first ideal diode circuit 41a, and an Nch MOSFET 32 is provided on the output side of the first ideal diode circuit 41a. A comparator 33 compares the source-drain voltage of the Nch MOSFET 31 with a predetermined value.

[0084] When turning on the Nch MOSFET 31, the first controller 34 controls the gate voltage of the Nch MOSFET 31 based on the output of the comparator 33 so that the source voltage of the Nch MOSFET 31 is higher than the drain voltage by a predetermined value. The output of the comparator 33 indicates whether the source voltage of the Nch MOSFET 31 is higher than the drain voltage by the predetermined value. The predetermined value is set in the comparator 33. The predetermined value is set to a value lower than the forward voltage of the diode element. Therefore, by using the first ideal diode circuit 41a, the forward voltage can be made closer to 0 V than in a configuration using a diode element. Furthermore, the predetermined value is set to a value that can prevent current from flowing backward from the drain to the source of the Nch MOSFET 31. Therefore, current can be prevented from flowing backward from the drain to the source of the Nch MOSFET 31.

[0085] The second controller 35 keeps the Nch MOSFET 32 in a full-on state at all times. The two Nch MOSFETs 31, 32 are connected back-to-back. By connecting the two Nch MOSFETs 31, 32 back-to-back, reverse current flow from the second output section 42 to the first output section 41 is prevented.

[0086] 4, the second output section 42 includes a second ideal diode circuit 42a, similar to the first output section 41. The second ideal diode circuit 42a may include two Nch-type MOSFETs 61 and 62, a comparator 63, a first controller 64, and a second controller 65, similar to the first ideal diode circuit 41a. The configuration of the second ideal diode circuit 42a is similar to that of the first ideal diode circuit 41a, and therefore a detailed description thereof will be omitted.

[0087] 4 includes the comparator 33, the first ideal diode circuit 41a may include an operational amplifier instead of the comparator. Similarly, the second ideal diode circuit 42a may include an operational amplifier instead of the comparator 63.

[0088] 1-6. State transition of the second output section Next, the state transition of the second output unit 42 included in the digital camera 100 of this embodiment will be described with reference to Figures 2, 4, and 5. As shown in Figures 2 and 4, in this embodiment, the camera controller 160 controls the state of the second output unit 42.

[0089] In more detail, the state of the second output unit 42 can be switched between a conductive state in which the second voltage (set voltage VS) is permitted to be conducted and a non-conductive state in which the second voltage (set voltage VS) is blocked from being conducted, and the camera controller 160 switches the state of the second output unit 42 between the conductive state and the non-conductive state. When the second output unit 42 is in the conductive state, the first output unit 41 and the second output unit 42 form a diode OR circuit. When the second output unit 42 is in the non-conductive state, the first voltage output from the first output unit 41 is supplied to the first voltage generating unit 2a as an input voltage. The camera controller 160 is an example of a "control unit."

[0090] Specifically, the camera controller 160 switches the state of the second ideal diode circuit 42a described with reference to FIG. 4 between a conductive state and a non-conductive state. When the second ideal diode circuit 42a is in the conductive state, it functions as an ideal diode circuit. When the second ideal diode circuit 42a is in the non-conductive state, it does not conduct the set voltage VS output from the second voltage generator 2b. More specifically, when switching the second ideal diode circuit 42a to the non-conductive state, the camera controller 160 outputs control signals to the first controller 64 and the second controller 65 to turn off the two Nch-type MOSFETs 61 and 62.

[0091] Even if the second output section 42 is in a non-conductive state, the supply of the third power to the third load 91 described with reference to FIG. 2 is maintained.

[0092] Fig. 5 is a diagram showing the relationship between the operation modes of the digital camera 100 of this embodiment and two states of the second output unit 42. In detail, Fig. 5 shows table information TA that the camera controller 160 refers to in order to control the state of the second output unit 42. The table information TA is stored in the memory or flash memory 161 within the camera controller 160.

[0093] 5, in this embodiment, the camera controller 160 refers to the table information TA to turn on the second output unit 42 when the operation mode of the digital camera 100 is the still image capture mode, and turn off the second output unit 42 when the operation mode of the digital camera 100 is the video capture mode. In this embodiment, the still image capture mode is an example of a "first operation mode," and the video capture mode is an example of a "second operation mode different from the first operation mode." Furthermore, the video capture mode is an example of an "operation mode in which the power consumption of the imaging device is greater than that of the first operation mode."

[0094] According to this embodiment, by putting the second output section 42 into a non-conductive state when the operation mode of the digital camera 100 is the moving image shooting mode, it is possible to reduce the power consumption of the digital camera 100.

[0095] Specifically, the efficiency with which the DC / DC converter included in the second voltage generating unit 2b converts the battery voltage to the set voltage VS is lower than the efficiency with which the switched capacitor 51 converts the battery voltage to a voltage 1 / n times lower. Therefore, the longer the period during which the second voltage (set voltage VS) is supplied as an input voltage to the first voltage generating unit 2a, the greater the power loss, and the greater the power consumption of the digital camera 100. Therefore, if the output unit 4 is configured to constantly supply the second voltage (set voltage VS) output from the second voltage generating unit 2b to the first voltage generating unit 2a as an input voltage after the battery voltage drops and the first voltage output from the first supply line 5 drops to a voltage value below the set voltage VS, the power consumption of the digital camera 100 increases, and the rate at which the remaining capacity of the internal battery 162 decreases increases. In contrast, in this embodiment, the second output unit 42 is made non-conductive in one of the two operating modes (still image capture mode and video capture mode) (video capture mode). Therefore, compared to a configuration in which the output unit 4 functions as a diode OR circuit in either of the two operation modes, the period during which the second voltage (set voltage VS) is supplied as an input voltage to the first voltage generating unit 2a can be shortened, thereby reducing the power consumption of the digital camera 100.

[0096] As described with reference to FIG. 2 , in this embodiment, the second voltage (set voltage VS) output from the second voltage generating unit 2b is supplied to the third load 91 via the fourth supply line 9. Therefore, if the output unit 4 is configured to constantly supply the second voltage (set voltage VS) as an input voltage to the first voltage generating unit 2a after the battery voltage drops and the first voltage drops to a voltage value less than the set voltage VS, there is a possibility that the power supplied to the first load 3 will be insufficient. This requires increasing the circuit size of the second voltage generating unit 2b. In contrast, according to this embodiment, the period during which the second voltage (set voltage VS) is supplied as an input voltage to the first voltage generating unit 2a can be shortened. This makes it less likely that the power supplied to the first load 3 will be insufficient. Therefore, the circuit size of the second voltage generating unit 2b can be reduced compared to a configuration in which the output unit 4 constantly functions as a diode OR circuit.

[0097] Note that mechanical shutter 152 operates only in still image shooting mode. That is, mechanical shutter drive unit 153 drives when digital camera 100 is in still image shooting mode, and does not drive when digital camera 100 is in video shooting mode. Therefore, when digital camera 100 is in video shooting mode, there is no sudden large drop in battery voltage, so even if second output unit 42 is made non-conductive, first voltage generation unit 2a is unlikely to stop operating due to a sudden change in battery voltage.

[0098] 1-7. Modification of the output unit Next, a modified example of the output section 4 will be described with reference to Fig. 6. Fig. 6 is a circuit diagram that schematically shows the configuration of a modified example of the output section 4 included in the digital camera 100 of this embodiment. As shown in Fig. 6, the first output section 41 may be formed of a diode element 411. Furthermore, the second output section 42 may be formed of two N-channel MOSFETs 421 and 422 that are connected back-to-back.

[0099] The camera controller 160 controls the on and off states of the two Nch-type MOSFETs 421 and 422. Specifically, when a diode OR circuit is formed by the first output section 41 and the second output section 42, the camera controller 160 sets the Nch-type MOSFET 421 to the off state and the Nch-type MOSFET 422 to the on state. Furthermore, when the second output section 42 is set to a non-conductive state, the camera controller 160 sets the Nch-type MOSFET 421 to the off state and the Nch-type MOSFET 422 to the off state.

[0100] 6, a diode OR circuit can be configured by first output section 41 and second output section 42. This makes it possible to prevent the malfunction of first voltage generating section 2a stopping operation and shutting down digital camera 100 when mechanical shutter 152 is driven.

[0101] 6, by configuring the first output section 41 with a diode element 411, it is possible to prevent a reverse current flow from the second output section 42 to the first output section 41. Furthermore, by configuring the second output section 42 with two Nch-type MOSFETs 421 and 422 connected back-to-back, it is possible to prevent a reverse current flow from the first output section 41 to the second output section 42. Furthermore, according to the modification shown in FIG. 6, it is possible to switch the state of the second output section 42 between a conductive state and a non-conductive state.

[0102] As shown in FIG. 6, the two Nch-type MOSFETs 421 and 422 each have a parasitic diode, but the second output section 42 may further have a diode element connected in parallel to each of the two Nch-type MOSFETs 421 and 422.

[0103] 6, the second output section 42 has two Nch-type MOSFETs 421 and 422 connected back-to-back, but the second output section 42 may have a diode element instead of the Nch-type MOSFET 421. In other words, the second output section 42 may be composed of a diode element and the Nch-type MOSFET 422.

[0104] 2. Effects etc. An embodiment of the present disclosure has been described above with reference to the drawings (FIGS. 1 to 6). According to this embodiment, a digital camera 100 or a camera body 150, which is an example of an imaging device that operates by consuming power based on a battery voltage output from an internal battery 162, which is an example of a battery, includes a first voltage generating unit 2a, a first load 3, a third supply line 7, a second voltage generating unit 2b, and an output unit 4. The first voltage generating unit 2a generates an output voltage from an input voltage. The first load 3 is supplied with a first power based on the output voltage of the first voltage generating unit 2a. The third supply line 7 supplies a second power to a second load 8 based on the battery voltage. The second voltage generating unit 2b generates a second voltage (set voltage VS) from the battery voltage. The output unit 4 supplies the higher voltage, either the first voltage (variable voltage) or the second voltage (set voltage VS), which drops when the second power is supplied to the second load 8, as an input voltage to the first voltage generating unit 2a. As a result, a malfunction in which the input voltage of the first voltage generating unit 2a falls below the lower limit VL when power is supplied to the second load 8 is unlikely to occur. Therefore, a malfunction in which the operation of the first voltage generating unit 2a stops and the digital camera 100 shuts down when the second load 8 is driven is unlikely to occur. Therefore, according to this embodiment, the digital camera 100 can be operated stably.

[0105] Furthermore, the occurrence of the above-mentioned problems can be prevented by providing a dedicated voltage generating unit or dedicated battery that supplies voltage only to the output unit 4 instead of the second voltage generating unit 2b. However, in this configuration, the need to provide a dedicated voltage generating unit or dedicated battery increases the size of the digital camera 100. In contrast, according to this embodiment, the second voltage generating unit 2b that supplies power to the third load 91 is used, so the increase in size of the digital camera 100 can be prevented.

[0106] Furthermore, according to this embodiment, the digital camera 100 or camera body 150, which is an example of an imaging device, further includes a step-down circuit (switched capacitor 51) that steps down the battery voltage to generate a first voltage (variable voltage), and thus the first voltage (variable voltage) obtained by stepping down the battery voltage can be supplied to the first voltage generation unit 2a. Therefore, voltage conversion can be performed more efficiently than in a configuration in which the first voltage generation unit 2a steps down the battery voltage to generate a voltage to be supplied to the first load 3. This makes it possible to reduce the power consumption of the digital camera 100. In particular, according to this embodiment, the switched capacitor 51, which has higher voltage conversion efficiency than a DC / DC converter, is used as the step-down circuit, and therefore voltage conversion can be performed more efficiently. This makes it possible to further reduce the power consumption of the digital camera 100.

[0107] Furthermore, according to this embodiment, the output unit 4 includes a first output unit 41 that outputs the first voltage (fluctuation voltage) when the first voltage (fluctuation voltage) is equal to or greater than the voltage value of the second voltage (set voltage VS), and a second output unit 42 that outputs the second voltage (set voltage VS) when the second voltage (set voltage VS) is equal to or greater than the voltage value of the first voltage (fluctuation voltage). The first output unit 41 prevents a current based on the second voltage (set voltage VS) from flowing backward from the second output unit 42 to the first output unit 41. The second output unit 42 prevents a current based on the first voltage (fluctuation voltage) from flowing backward from the first output unit 41 to the second output unit 42.

[0108] Furthermore, according to this embodiment, the first output section 41 includes a first ideal diode circuit 41a. Therefore, according to this embodiment, it is possible to suppress the power consumed by the first output section 41, thereby reducing the power consumption of the digital camera 100. Furthermore, since the first output section 41 includes the first ideal diode circuit 41a, it is possible to prevent a current based on the second voltage (set voltage VS) from flowing back from the second output section 42 to the first output section 41 when the second voltage (set voltage VS) is equal to or higher than the voltage value of the first voltage (variable voltage).

[0109] Furthermore, according to this embodiment, the second output section 42 includes the second ideal diode circuit 42a. Therefore, according to this embodiment, it is possible to suppress the power consumed by the second output section 42 and reduce the power consumption of the digital camera 100. Furthermore, since the second output section 42 includes the second ideal diode circuit 42a, it is possible to prevent a current based on the first voltage (fluctuating voltage) from flowing back from the first output section 41 to the second output section 42 when the first voltage (fluctuating voltage) is equal to or higher than the voltage value of the second voltage (set voltage VS).

[0110] Furthermore, in a configuration in which the second output unit 42 cannot be transitioned to a non-conductive state, after the battery voltage drops and the first voltage output from the first supply line 5 drops to a voltage value less than the set voltage VS, the second voltage (set voltage VS) is constantly supplied to the first voltage generation unit 2a as an input voltage. Therefore, the second voltage (set voltage VS) must be supplied to the first voltage generation unit 2a as an input voltage in either operation mode, which requires a larger circuit size for the second voltage generation unit 2b. In contrast, according to this embodiment, the second output unit 42 can be switched between a conductive state that permits conduction of the second voltage (set voltage VS) and a non-conductive state that blocks conduction of the second voltage (set voltage VS). The digital camera 100 or the camera body 150, which is an example of an imaging device, further includes a camera controller 160, which is an example of a control unit that switches the state of the second output unit 42 between a conductive state and a non-conductive state. This allows the second output unit 42 to transition to a non-conductive state. Therefore, the circuit scale of the second voltage generating unit 2b can be reduced compared to a configuration in which the second output unit 42 cannot be brought into a non-conductive state, and therefore, an increase in the size of the digital camera 100 can be prevented.

[0111] Furthermore, according to this embodiment, digital camera 100 or camera body 150, which is an example of an imaging device, has, as its operation modes, a still image capture mode, which is an example of a first operation mode, and a video capture mode, which is an example of a second operation mode, and camera controller 160, which is an example of a control unit, brings second output unit 42 into a conductive state when the operation mode is the still image capture mode (first operation mode), and brings second output unit 42 into a non-conductive state when the operation mode is the video capture mode (second operation mode). Therefore, according to this embodiment, the state of second output unit 42 can be switched between a conductive state and a non-conductive state by switching the operation mode.

[0112] Furthermore, according to this embodiment, second load 8 includes mechanical shutter drive unit 153, which is an example of an actuator, and mechanical shutter drive unit 153 is driven when the operation mode is a still image capture mode (first operation mode) and is not driven when the operation mode is a video capture mode (second operation mode). Therefore, according to this embodiment, second output unit 42 can be brought into a non-conductive state during video capture mode. Therefore, the state of second output unit 42 can be switched between a conductive state and a non-conductive state depending on the change in operation mode.

[0113] Furthermore, according to this embodiment, the second operation mode includes a video shooting mode in which the digital camera 100 or the camera body 150 consumes more power than the still image shooting mode (first operation mode). Therefore, according to this embodiment, the second output unit 42 can be brought into a non-conductive state during the video shooting mode in which power consumption is high. This allows the circuit size of the second voltage generation unit 2b to be reduced compared to a configuration in which the second output unit 42 cannot be brought into a non-conductive state.

[0114] Furthermore, according to this embodiment, the digital camera 100 or camera body 150, which is an example of an imaging device, further includes a third load 91 to which the third power is supplied, and a fourth supply line 9 that supplies the third power based on the set voltage VS to the third load 91. Therefore, according to this embodiment, the second voltage generation unit 2b that supplies power to the third load 91 is used, and therefore an increase in the size of the digital camera 100 can be suppressed.

[0115] [Other embodiments] The present disclosure is not limited to the above-described embodiments and can be implemented in various forms without departing from the spirit of the present disclosure. Furthermore, the components disclosed in the above-described embodiments can be modified as appropriate. For example, some of the components shown in one embodiment may be added to the components of another embodiment, or some of the components shown in one embodiment may be deleted from the embodiment.

[0116] The drawings mainly show each component in a schematic manner to facilitate understanding, and the thickness, length, number, spacing, etc. of each component shown in the drawings may differ from the actual ones due to the convenience of creating the drawings. Furthermore, the configurations of each component shown in the above embodiment are merely examples and are not particularly limited, and it goes without saying that various modifications are possible within a scope that does not substantially deviate from the effects of the present disclosure.

[0117] For example, in the embodiment described with reference to Figures 1 to 6, the camera body 150 is provided with a CMOS image sensor 154, but the camera body 150 may have other imaging elements such as an NMOS image sensor or a CCD image sensor instead of the CMOS image sensor 154.

[0118] 1 to 6, a memory card MC is used as an example of an external memory, but the external memory is not limited to a memory card MC. For example, a recording medium such as an optical disc may be used as the external memory.

[0119] Furthermore, in the embodiment described with reference to Figures 1 to 6, power is supplied to the camera controller 160 from three voltage generation units (voltage generation units 2b, 21a, and 21b), but power may be supplied to the camera controller 160 from four or more voltage generation units.

[0120] In the embodiment described with reference to FIGS. 1 to 6, the step-down circuit (switched capacitor 51) is provided in the first supply line 5, but the step-down circuit (switched capacitor 51) may be omitted.

[0121] 1 to 6, second load 8 includes an actuator that drives mechanical shutter 152, but second load 8 is not particularly limited as long as it is a load that reduces the first voltage output from first supply line 5 from a voltage value equal to or greater than lower limit VL of first voltage generating unit 2a to a voltage value less than lower limit VL. For example, second load 8 may include an actuator included in drive unit 103 of interchangeable lens 101.

[0122] Furthermore, in the embodiment described with reference to FIGS. 1 to 6, digital camera 100 includes second load 8 (mechanical shutter driving unit 153), but second load 8 may be a load provided in an external device of digital camera 100. For example, second load 8 may include an actuator included in driving unit 103 of interchangeable lens 101. Interchangeable lens 101 is an external device of digital camera 100. More specifically, multiple types of interchangeable lenses 101 can be attached and detached to camera body 150, and the user can use multiple types of interchangeable lenses 101 and attach them to camera body 150 as needed.

[0123] 1 to 6, the digital camera 100 is provided with a battery (internal battery 162), but the battery is not limited to the internal battery 162 as long as it can supply driving power for the digital camera 100. For example, the battery may be a battery (external battery) built into a camera accessory such as a battery grip.

[0124] Furthermore, in the embodiment described with reference to FIGS. 1 to 6, the second operation mode was a moving image capture mode, but the second operation mode is not limited to the moving image capture mode. For example, the second operation mode may include a playback image output mode in which image data is output from the HDMI (registered trademark) terminal 159 and a still image or a moving image is displayed on an external display device. The power consumption of the digital camera 100 when operating in the playback image output mode is greater than that in the still image capture mode. Therefore, the playback image output mode is another example of a "mode in which the power consumption of the digital camera 100 is greater than that in the first operation mode."

[0125] Furthermore, in the embodiment described with reference to FIGS. 1 to 6, the digital camera 100 with an interchangeable lens has been described as an example of an imaging device, but the imaging device may also be an integrated lens type.

[0126] 1 to 6, the digital camera 100 is an example of an imaging device, but the imaging device of the present disclosure is not limited to the digital camera 100. The imaging device of the present disclosure is applicable to various imaging devices that operate by consuming power based on the battery voltage output from a battery. For example, the imaging device of the present disclosure is applicable to imaging devices implemented in movie cameras and smartphones.

[0127] [Example of situation] The following describes exemplary aspects of the present disclosure.

[0128] [Aspect 1] An imaging device that operates by consuming power based on a battery voltage output from a battery, a first voltage generating unit that generates an output voltage from an input voltage; a first load to which a first power based on the output voltage is supplied; a supply line for supplying a second power to a second load based on the battery voltage; a second voltage generating unit that generates a set voltage from the battery voltage; an output unit that supplies, as the input voltage to the first voltage generating unit, a voltage having a higher voltage value out of a variable voltage that drops when the second power is supplied to the second load and the set voltage; An imaging device comprising:

[0129] [Aspect 2] 2. The imaging device according to aspect 1, further comprising: a step-down circuit that steps down the battery voltage to generate the variable voltage.

[0130] [Aspect 3] The output unit a first output unit that outputs the fluctuating voltage when the fluctuating voltage is equal to or greater than the voltage value of the set voltage; a second output unit that outputs the set voltage when the set voltage is equal to or greater than the voltage value of the variable voltage; Including, the first output unit prevents a current based on the set voltage from flowing back from the second output unit to the first output unit; 3. The imaging device according to aspect 1 or 2, wherein the second output unit prevents a current based on the fluctuating voltage from flowing back from the first output unit to the second output unit.

[0131] [Aspect 4] 4. The imaging device of claim 3, wherein the first output section includes an ideal diode circuit.

[0132] [Aspect 5] 5. The imaging device according to aspect 3 or 4, wherein the second output section includes an ideal diode circuit.

[0133] [Aspect 6] the second output unit is switchable between a conductive state that allows conduction of the set voltage and a non-conductive state that blocks conduction of the set voltage, 6. The imaging device according to any one of aspects 3 to 5, further comprising a control unit that switches the state of the second output unit between the conductive state and the non-conductive state.

[0134] [Aspect 7] the imaging device has, as operation modes, a first operation mode and a second operation mode different from the first operation mode; The imaging device of aspect 6, wherein the control unit sets the second output unit to the conductive state when the operation mode is the first operation mode, and sets the second output unit to the non-conductive state when the operation mode is the second operation mode.

[0135] [Aspect 8] the second load includes an actuator; 8. The imaging device of claim 7, wherein the actuator is driven when the operation mode is the first operation mode and is not driven when the operation mode is the second operation mode.

[0136] [Aspect 9] 9. The imaging device according to aspect 7 or 8, wherein the second operation mode includes an operation mode in which the power consumption of the imaging device is greater than that of the first operation mode.

[0137] [Aspect 10] a third load to which the third power is supplied; a supply line that supplies the third power based on the set voltage to the third load; The imaging device of any one of aspects 1 to 9, further comprising:

[0138] [Aspect 11] The imaging device of any one of aspects 1 to 10, further comprising the second load.

[0139] [Aspect 12] 12. The imaging device of claim 11, wherein the second load includes an actuator that drives a mechanical shutter.

[0140] [Aspect 13] 13. The imaging device of claim 1, further comprising the battery. [Industrial Applicability]

[0141] The present disclosure is applicable to various imaging devices that operate by consuming power based on the battery voltage output from a battery. [Explanation of symbols]

[0142] 2a First voltage generating unit 2b Second voltage generating unit 2c Third voltage generator 3 1st load 4 Output section 5. First Supply Line 6 Second Supply Line 7. Third Supply Line 8 2nd load 9. Fourth Supply Line 41 First output section 41a First ideal diode circuit 42 Second output section 42a Second ideal diode circuit 51 Switched Capacitor 91 Third load 100 digital cameras 103 Drive unit 131 Zoom lens drive unit 132 OIS drive unit 133 Focus lens drive unit 150 camera body 152 Mechanical Shutter 153 Mechanical shutter drive unit 160 Camera Controller 162 Internal Battery Va voltage (battery voltage) Vb voltage (fluctuation voltage) Vc voltage (set voltage) Vd voltage (input voltage) VL lower limit VS Set voltage

Claims

1. An imaging device that operates by consuming power based on a battery voltage output from a battery, a first voltage generating unit that generates an output voltage from an input voltage; a first load to which a first power based on the output voltage is supplied; a supply line for supplying a second power to a second load based on the battery voltage; a second voltage generating unit that generates a set voltage from the battery voltage; an output unit that supplies, as the input voltage to the first voltage generating unit, a voltage having a larger voltage value out of a variable voltage that drops when the second power is supplied to the second load and the set voltage; Equipped with the varying voltage is supplied based on the battery voltage; the fluctuating voltage fluctuates from a voltage value greater than the set voltage to a voltage value less than the set voltage, and then fluctuates from a voltage value less than the set voltage to a voltage value greater than the set voltage, in response to an operation of the second load; The output unit When the fluctuating voltage fluctuates from a voltage value greater than the set voltage to a voltage value less than the set voltage, the set voltage is supplied to the first voltage generating unit as the input voltage; When the fluctuating voltage fluctuates from a voltage value smaller than the set voltage to a voltage value larger than the set voltage, the fluctuating voltage is supplied to the first voltage generating unit as the input voltage.

2. The imaging device according to claim 1 , further comprising a step-down circuit that steps down the battery voltage to generate the fluctuating voltage.

3. The output unit a first output unit that outputs the fluctuating voltage when the fluctuating voltage is equal to or greater than the voltage value of the set voltage; a second output unit that outputs the set voltage when the set voltage is equal to or greater than the voltage value of the variable voltage; Including, the first output unit prevents a current based on the set voltage from flowing back from the second output unit to the first output unit; The imaging device according to claim 1 , wherein the second output section prevents a current based on the fluctuating voltage from flowing backward from the first output section to the second output section.

4. The imaging device according to claim 3 , wherein the first output section includes an ideal diode circuit.

5. The imaging device according to claim 3 , wherein the second output section includes an ideal diode circuit.

6. the second output unit is switchable between a conductive state that allows conduction of the set voltage and a non-conductive state that blocks conduction of the set voltage, The imaging device according to claim 3 , further comprising a control unit that switches the state of the second output unit between the conductive state and the non-conductive state.

7. the imaging device has, as operation modes, a first operation mode and a second operation mode different from the first operation mode; 7. The imaging device according to claim 6, wherein the control unit sets the second output unit to the conductive state when the operation mode is the first operation mode, and sets the second output unit to the non-conductive state when the operation mode is the second operation mode.

8. the second load includes an actuator; The imaging device according to claim 7 , wherein the actuator is driven when the operation mode is the first operation mode, and is not driven when the operation mode is the second operation mode.

9. The imaging device according to claim 7 , wherein the second operation mode includes an operation mode in which power consumption of the imaging device is greater than that of the first operation mode.

10. a third load to which a third power is supplied; a supply line that supplies the third power based on the set voltage to the third load; The imaging device of claim 1 , further comprising:

11. The imaging device of claim 1 , further comprising the second load.

12. The imaging device according to claim 11 , wherein the second load includes an actuator that drives a mechanical shutter.

13. The imaging device of claim 1 , further comprising the battery.

Images