JPH0990488A - Electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use the equipment in any accessory by lowering supply voltage in the case the accessory can be operated at lower voltage than the voltage at which all the accessories can be operated. SOLUTION: At the time of detecting that a lens mount detection switch 8 is turned on, a microcomputer 3 outputs 'H' to the output voltage switching terminal 5V/3V of a DC/DC converter 2 from a (cont) terminal so as to set output voltage to 5V. The kind of the lens is read out from the microcomputer 9 of the lens according to communication to discriminate whether the moutned lens can be operated even at 3V. In the case it can be operated at 3V, the microcomputer 3 sets the (cont) terminal to 'L' to change the output voltage of the converter 2 to 3V, and finishes the setting of power source voltage. The power source voltage is set to the voltage at which the electric circuits of all the lenses that can be mounted and the electric circuit of the camera can be operated. Thereafter, the kind of the lens (operating voltage) is discriminated and the power source voltage is lowered in the case the lens which can be operated even at the low voltage is mounted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in electronic equipment such as a camera which supplies a power supply voltage to an interchangeable lens to bring the interchangeable lens into an operable state.

[0002]

2. Description of the Related Art In a conventional interchangeable lens type autofocus camera or the like, electronic information is stored in order to store individual information of the interchangeable lens and transmit the information to the camera and to drive an actuator in the lens. Interchangeable lenses with built-in circuits are often used. In many cases, these interchangeable lenses do not have a power source in the lens, but are supplied with power from electronic circuits and actuators from the camera body.

Further, in recent years, semiconductors including microcomputers have been reduced in voltage, and a circuit which has conventionally required a voltage of about 5V is 3V.
It is designed to operate with a voltage of the order of magnitude. Therefore, in order to save energy and prevent heat generation, a power source of about 3V is often used.

[0004]

However, in an interchangeable lens type camera using a lens having an electronic circuit as the interchangeable lens, an old type interchangeable lens having an electronic circuit requiring a voltage of about 5 V is also mounted. Therefore, even if semiconductor technology advances and low-voltage operation becomes possible, it is necessary to supply a high voltage to the lens in consideration of the latter type of interchangeable lens.

Therefore, in order to reduce the voltage of the entire camera system, it is necessary to lower the voltage supplied to the lens after taking measures such as making it impossible to mount an old type lens. In that case, the old type lens would be completely wasted.

Therefore, it has been difficult to reduce the power supply voltage of the entire camera system in order to save energy.

(Object of the Invention) An object of the present invention is to provide an electronic device which can be used regardless of which accessory is attached and which can achieve power saving when the accessory is used. .

[0008]

In order to achieve the above object, the present invention according to claims 1 and 2 is such that when an accessory is attached to the electronic device, all the accessories attachable to the electronic device are Once the operable voltage is supplied, then the operable voltage of the attached accessories is determined, and if all the accessories can be operated at a voltage lower than the operable voltage, the accessory is supplied to the accessory. The power supply voltage is switched to the lowest operable voltage of the accessory.

Further, according to the present invention as set forth in claims 3 and 4, when the electronic device is reset, a voltage that enables all accessories that can be attached to the electronic device is once supplied,
After that, the operable voltage of the attached accessories is determined, and if all the accessories can operate at a voltage lower than the operable voltage, the power supply voltage to be supplied to the accessory is set to the operable voltage of the accessory. The voltage is switched to the lowest voltage.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail based on the illustrated embodiments.

FIG. 1 is a diagram showing an example of a specific configuration of an electric control block of a camera system according to the first embodiment of the present invention. First, the configuration of each unit will be described.

Reference numeral 1 is a battery which is a power source for the entire camera, and 2 is a DC / DC converter which is a power source circuit for stabilizing the power source using the battery 1 as a power source and supplying it to the circuit. The output voltage is 5V and 3V. Input terminal to switch to 5V /
I have 3V. 3 is a microcomputer (hereinafter, referred to as a control circuit for controlling the entire camera system)
The microcomputer has a cont terminal for controlling the 5V / 3V terminal of the DC / DC converter 2 in order to switch the output voltage of the DC / DC converter 2.
The microcomputer 3 can operate at a power supply voltage of 3V to 5V.

Reference numeral 4 is a power supply terminal B for directly supplying power from the battery 1 to the interchangeable lens, and 5 is DC / DC to the interchangeable lens.
Power supply terminals C, 6a for supplying the output of the converter 2
6c are three communication terminals for the control circuit 3 to communicate with the lens control circuit, 7 is a ground terminal to which an interchangeable lens is connected, and 8 is a lens attachment detection switch for detecting that an interchangeable lens is attached. is there.

Reference numeral 9 is a microcomputer which is a control circuit for controlling the lens and storing lens information, 10 is a motor which is an actuator for focusing the lens, and 11 is a motor which is controlled by the microcomputer 9 in the lens. Is connected to a power supply terminal B of the camera when a lens is attached to the camera, and power supply terminals LB and 13 for receiving power supply of the motor 10 and the motor drive circuit 11 are When the lens is attached to the camera, it is connected to the power supply terminal C of the camera, and power supply terminals LC and 14a for receiving the power supply of the microcomputer 9 in the lens
14c are three communication terminals for the microcomputer in the lens to communicate with the microcomputer 3 of the camera, and 15 is a ground terminal of the lens.

Here, the interchangeable lens to be mounted has a different operable voltage of the microcomputer 9 depending on the lens.
There are two types, one that operates only when the voltage supplied from the power supply terminal LC is 5V and one that operates at a voltage of 3V to 5V. The camera microcomputer 3 communicates these two types of lens discrimination with the microcomputer 9 via communication terminals 6a to 6c, 14a.
It is determined whether the lens operates only at 5V or the lens operates at 3V to 5V by the communication performed via 14c.

This communication is performed by a known 8-bit serial communication, and as shown in FIG. 2, a request code for transmitting the lens ID by the microcomputer 3 of the camera (here, "0" in binary).
0000101 ") is sent to the lens microcomputer 9, the lens microcomputer 9 is a binary number" 0 ******** "(* depends on the lens) in the case of a lens that can operate only at 5V. Send back the lens ID and 3V to 5V
In case of a lens that can be operated with, the binary number "1 *****"
"**" (* depends on the lens) is sent back.

If the most significant bit of the lens ID code sent back from the lens microcomputer 9 is "0", the lens operates only at 5V, and if it is "1", the lens operates at 3V to 5V. It is determined to be a lens that does.

In the above structure, when the battery 1 is attached to the camera and the main switch (not shown) is turned on, DC / D
Power is supplied to the C converter 2, and the DC / DC converter 2 is activated. As a result, power is supplied to the microcomputer 3 of the camera and the microcomputer 3 starts operating. If the lens is attached at this time, the microcomputer 9 of the lens is also supplied with power to start the operation.

FIG. 3 is a flow chart when the microcomputer 3 of the camera sets the voltage of the power supply, and when the interchangeable lens is attached when the battery 1 is attached due to the battery exchange, or when the lens is exchanged. It is executed to set the voltage of the power supply when the interchangeable lens is attached to the camera.

When the microcomputer 3 detects that the lens mounting detection switch 8 is turned on, it starts executing the power supply voltage setting shown in FIG.

In step # 101, the microcomputer 3
Outputs "H" (meaning high level) to the output voltage switching terminal 5V / 3V of the DC / DC converter 2 through the cont terminal to set the output voltage to 5V. As a result, the DC / DC converter 2 outputs the output voltage switching terminal 5
Since V / 3V is "H", 5V is output. If it is "L" (meaning low level), 3
V will be output. This DC / DC converter 2
There are a plurality of methods for switching the voltage of (1), such as a method of changing the reference voltage of the DC / DC converter and a method of switching the two power sources, but since it is already known here, the description thereof will be omitted.

Here, the output voltage is set to 5V by
This is because it is possible to operate any lens because the voltage required for the mounted lens is unknown.

In the next step # 102, the lens type is read from the lens microcomputer 9 by communication.
Then, in the next step # 103, it is determined from the lens ID code read from the lens microcomputer 9 in step # 102 whether or not the mounted lens can operate even at 3V.

As a result of the above determination, if operation is possible even at 3V, the process proceeds to step # 104, the microcomputer 3 sets the cont terminal to "L", changes the output voltage of the DC / DC converter 2 to 3V, and sets the power supply voltage. To finish. If it is not operable at 3V, the power supply voltage setting is terminated at this point.

When the setting of the power supply voltage is completed as described above, the camera operates at the set power supply voltage until the lens is removed or replaced.

As described above, when it is attached to the camera,
For the time being, set the power supply voltage to the operable voltage of the electric circuits of all the lenses that can be attached and the electric circuit of the camera, and then determine the lens type (determine the operating voltage), and the lens that can operate even at low voltage is attached. If so, the power supply voltage is reduced.

(Second Embodiment) FIG. 4 is a diagram showing an example of a specific configuration of an electric control block of a camera system according to a second embodiment of the present invention. First, the configuration of each part will be described. To do.

Reference numeral 51 denotes a battery which is a power source for the entire camera, and 52
Is a DC / DC converter which is a power supply circuit for stabilizing the power supply using the battery 51 as a power supply and supplying the power to the circuit.
Output 3V. A DC / DC converter 53 is a power supply circuit for stabilizing the power supply using the battery 51 as a power supply and supplying the power to the circuit, and has an input terminal 5V / 3V for switching the output voltage between 5V and 3V.

Reference numeral 54 denotes a microcomputer which is a control circuit for controlling the entire camera system using the DC / DC converter 52 as a power source. It is a DC / DC converter 53 for switching the output voltage of the DC / DC converter 53.
It has a cont terminal for controlling the V / 3V terminal. The voltage switching of this DC / DC converter is 5V / 3V
5V voltage is output by setting the terminal to “H”
3V is output by setting the / 3V terminal to "L".

55 is a power supply terminal B for directly supplying power from the battery 51 to the interchangeable lens, and 56 is DC to the interchangeable lens.
A power supply terminal C for supplying the output of the / DC converter 53, 57a to 57c are three communication terminals for the control circuit 54 to communicate with the control circuit of the lens, 58 is a ground terminal connected to the interchangeable lens, Reference numeral 59 is a lens mounting detection switch for detecting mounting of the interchangeable lens.

Reference numeral 60 is a microcomputer which is a control circuit for controlling the inside of the lens and storing lens information, 61 is a motor which is an actuator for focusing the lens, and 62 is a motor which is controlled by the microcomputer 60 in the lens, and the motor 61 is used.
A motor drive circuit for driving the camera, 63 is connected to the power terminal B of the camera when the lens is attached to the camera,
The power supply terminals LB and 64 for receiving the power supply of the motor 61 and the motor drive circuit 62 are connected to the power supply terminal C of the camera when the lens is mounted on the camera and receive the power supply of the microcomputer 60 in the lens. Power supply terminal LC of
Reference numerals 65a to 65c are three communication terminals for the microcomputer 60 in the lens to communicate with the microcomputer 54 of the camera, and 66 is a ground terminal of the lens.

Here, the microcomputer 54 operates at 3V with the DC / DC converter 52 as a power source. Also,
The control circuit including the microcomputer 60 of the lens includes one that operates only at 5V and one that operates at 3V to 5V depending on the type of lens. The camera microcomputer 54
Communication terminal 57a with microcomputer 60 for discriminating the type of lens
5V by communication performed via 57c and 65a to 65c
It is determined whether the lens operates only at or the lens operates at 3V to 5V.

In the above structure, as to the method for determining the operating voltage of the mounted lens, as in the method described in the first embodiment, when the lens is mounted, the microcomputer 54 changes the CONT terminal to "H". ", And setting the output of the DC / DC converter 53 to 5V, supplies a voltage at which all the lenses can operate to the lens microcomputer 6
0 is communicated with and the operating voltage of the lens is determined from the ID code of the lens.

When the operating voltage of the lens is determined,
If a lens that can operate even at a low voltage is mounted according to the operating voltage of the lens, the cont.
By setting the terminal to "L" and setting the output voltage of the DC / DC converter 53 to 3V, the power supply voltage supplied to the microcomputer 60 of the lens is set to 3V, and when a lens that can operate only at 5V is mounted, The power supply voltage setting is completed with the power supply voltage kept at 5V.

As described above, a constant voltage is supplied to the microcomputer 54 which is the control circuit of the camera, and when the microcomputer 54 is mounted on the camera, the power supply voltage is set to the operable voltage of the electric circuits of all the lenses which can be mounted for the time being. After that, the lens type is determined (the operating voltage is determined), and if a lens that can operate even at a low voltage is attached, the power supply voltage is reduced.

Here, the difference between the first embodiment and the second embodiment will be described.

In the configuration of FIG. 1, the power of the camera and the lens is supplied from one DC / DC converter. Therefore, by switching the output voltage of the DC / DC converter, the power supply of the entire system of the camera and the lens is switched. In this configuration, DC
Since there is only one / DC converter, it has the effect of simplifying the circuit configuration, but the operating voltage of the camera microcomputer must be compatible with a wide range of power supply that corresponds to the entire output voltage range of the DC / DC converter. There wasn't.

On the other hand, in the configuration of FIG. 4, a dedicated single output DC / DC for supplying power to the microcomputer in the camera.
The converter and the output voltage switching type DC / DC converter that supplies power to the microcomputer of the lens supply power, and the power is independent.

This system has a problem that a plurality of DC / DC converters are required, but it has an effect that it can be configured with a camera microcomputer having a narrow operating voltage range. In recent years, microcomputers and the like have been limited in operating voltage upper limit due to miniaturization of processes, and many of them operate at a low power supply voltage in a narrow power supply voltage range. Therefore, it can be said that they are suitable for this type.

According to each of the above embodiments, the operable voltage of the interchangeable lens is detected when the interchangeable lens is mounted, and the highest voltage among the operable voltages of the interchangeable lens is supplied, You can use old interchangeable lenses that operate only at high voltage and new interchangeable lenses that operate at low to high voltage, and operate at low voltage when it is determined that a new interchangeable lens has been installed. Therefore, it is possible to operate the entire camera system at a low voltage and save energy.

(Correspondence between Invention and Embodiment) In the present embodiment, the microcomputer 3 or 54 corresponds to the operating voltage detecting means, and the microcomputer 3 or 54 (the portion that executes the operation in FIG. 3) also corresponds to the present invention. It corresponds to a power supply voltage changing means.

The above is the correspondence relation between each configuration of the embodiments and each configuration of the present invention, but the present invention is not limited to the configurations of these embodiments, and the functions shown in the claims,
It goes without saying that any structure may be used as long as the functions of the embodiments can be achieved.

(Modification) In each of the above embodiments, when the interchangeable lens is attached to the camera body, the power supply voltage is once set to the operable voltage of the electric circuits of all the attachable lenses, After that, the operating voltage of the interchangeable lens is determined, and if a lens that can operate at a low voltage is attached, the power supply voltage is reduced.However, when the camera system is reset, the power supply voltage is also set in the same manner. By setting, it is possible to achieve energy saving even in the subsequent use.

In each of the above embodiments, an interchangeable lens is taken as an example of an accessory to be attached to the camera. However, in addition to this, when power is supplied from the camera to the strobe, a date function and a camera control function are provided. When supplying power to the replaceable back cover, power can be supplied in the same manner. Furthermore, the accessory can be similarly applied as long as it is an accessory that can be attached to the camera and supplies power from the camera side.

Further, in each of the above-mentioned embodiments, the camera is taken as an example of the device main body for supplying power,
An electronic device that has a power source in the device body and supplies power to an accessory to be operated to operate the accessory (for example, a ROM cartridge of a (portable) game machine or various external expansion devices of a personal computer (PCMCIA card, etc.) ], The same is applicable.

[0046]

As described above, according to the present invention,
When an accessory is attached to the electronic device, or
At the time of resetting the electronic device, all the accessories that can be attached to the electronic device are once supplied with a voltage at which the accessory can be operated, and then the operable voltage of the accessory that is attached is discriminated. If the accessory is operable at a low voltage, the power supply voltage supplied to the accessory is switched to the lowest operable voltage of the accessory.

Therefore, it is possible to use any accessory to be mounted and to save electricity when the accessory is used.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic circuit configuration of a camera system according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining a communication command performed between the microcomputer of the camera and the microcomputer of the lens of FIG.

FIG. 3 is a flowchart showing an operation when setting a power supply voltage in the camera system of FIG.

FIG. 4 is a block diagram showing a schematic circuit configuration of a camera system according to a second embodiment of the present invention.

[Explanation of symbols]

1,51 battery 2,53 DC / DC converter capable of switching output voltage 3,54 microcomputer 9,60 lens microcomputer 10,61 lens 11,62 motor drive circuit 52 DC / DC converter for outputting a constant voltage

Claims (4)

[Claims] 1. An electronic device for supplying a power supply voltage to an accessory to be mounted to bring the accessory into an operable state, when the accessory is mounted to the electronic device, all the accessories mountable to the electronic device are Once the operable voltage is supplied, then the operable voltage of the attached accessories is determined, and if all the accessories can be operated at a voltage lower than the operable voltage, the accessory is supplied to the accessory. An electronic device, characterized in that the power supply voltage is switched to the lowest operable voltage of the accessory. 2. An electronic device for supplying a power supply voltage to an attached accessory to make the accessory operable, an operating voltage detecting means for detecting an operable voltage of the attached accessory, and an accessory for the electronic device. When is attached, all accessories that can be attached to the electronic device are once supplied with a voltage at which they can operate, and then the operating voltage detection means can operate at a voltage lower than the voltage at which all the accessories can operate. Is detected,
An electronic device comprising: a power supply voltage changing unit that switches a power supply voltage supplied to the accessory to a lowest voltage at which the accessory can operate. 3. An electronic device for supplying a power supply voltage to an accessory to be attached to bring the accessory into an operable state, when all the accessories attachable to the electronic device are operable when the electronic device is reset. Once, then determine the operable voltage of the attached accessories, when all the accessories were operable at a voltage lower than the operable voltage, the power supply voltage to be supplied to the accessory, An electronic device, characterized in that the voltage is switched to the lowest operable voltage of the accessory. 4. An electronic device that supplies a power supply voltage to an accessory that is attached to make the accessory operable, and an operating voltage detection unit that detects an operable voltage of the attached accessory, and a reset of the electronic device. Sometimes, it is possible that all accessories that can be attached to the electronic device are once supplied with a voltage at which they can be operated, and then the operating voltage detection means can operate at a voltage lower than the voltage at which all the accessories can operate. An electronic device comprising a power supply voltage changing means for switching the power supply voltage supplied to the accessory to the lowest operable voltage of the accessory when detected.