Abstract: Across the entire operating temperature range, and without requiring a new transistor element, the constant voltage output by a constant voltage circuit can be controlled to a voltage greater than or equal to the stop-oscillating voltage and as low as possible. A resistance 11b that negatively feeds back a reference current Iref is connected between the gate and source of a depletion mode n-channel transistor 11a configured to produce the reference current Iref on which the constant voltage VREG is based. The resistance of resistance 11b has a gradient to temperature change of the same sign as the gradient of the difference between the constant voltage and the stop-oscillating voltage to temperature change when the gradient of the resistance value of the resistance to temperature change is 0.

Abstract: Across the entire operating temperature range, and without requiring a new transistor element, the constant voltage output by a constant voltage circuit can be controlled to a voltage greater than or equal to the stop-oscillating voltage and as low as possible. A resistance 11b that negatively feeds back a reference current Iref is connected between the gate and source of a depletion mode n-channel transistor 11a configured to produce the reference current Iref on which the constant voltage VREG is based. The resistance of resistance 11b has a gradient to temperature change of the same sign as the gradient of the difference between the constant voltage and the stop-oscillating voltage to temperature change when the gradient of the resistance value of the resistance to temperature change is 0.

Abstract: An analog electronic timepiece is an analog electronic watch capable of displaying a plurality of types of calendar information, and includes a first index adapted to indicate the type of the calendar information, and a second index adapted to indicate a value of the calendar information of the type indicated by the first index.

Abstract: An analog electronic timepiece is an analog electronic watch capable of displaying a plurality of types of calendar information, and includes a first index adapted to indicate the type of the calendar information, and a second index adapted to indicate a value of the calendar information of the type indicated by the first index.

Abstract: An analog electronic timepiece including: a second hand; a driver configured to drive the second hand; a current time display processor configured to control the driver to move the second hand at a first time interval such that the second hand indicates a second of a current time; and a measured time display processor configured to control the driver to move the second hand at a second time interval different from the first time interval such that the second hand indicates a second of a measured time.

Abstract: An analog electronic timepiece including: a second hand; a driver configured to drive the second hand; a current time display processor configured to control the driver to move the second hand at a first time interval such that the second hand indicates a second of a current time; and a measured time display processor configured to control the driver to move the second hand at a second time interval different from the first time interval such that the second hand indicates a second of a measured time.

Abstract: An electronic device comprising a power source, a piezoelectric actuator A, and a drive control apparatus 100 for controlling the driving of the piezoelectric actuator, wherein the drive control apparatus 100 is provided with a drive circuit 111 for supplying a drive signal SDR to the piezoelectric element of the vibrating body 12, a phase difference detection means 120 for detecting the phase difference indicating the vibration state of the vibrating body 12, a comparison voltage setting circuit 133 for correcting the target phase difference to be the target for the vibration state, and a drive frequency setting means 140 for comparing the phase difference with the target phase difference; and the piezoelectric actuator A can be driven with high efficiency independent of the drive voltage by modifying the drive frequency of the drive signal SDR so that the phase difference approaches the target phase difference based on the results of the above comparison.

Abstract: In an electronic device 1 comprising a battery 200 and a piezoelectric actuator A, a power source voltage before drive control is started is maintained by a sample holding circuit 102, a reference voltage is set by a reference voltage generating circuit 103 on the basis of the power source voltage, and a control circuit 106 stops driving when the power source voltage falls below a drive stop voltage as compared by a second comparison circuit 105, and begins driving the piezoelectric actuator A again when the power source voltage exceeds the reference voltage as compared by a first comparison circuit 104. Therefore, the device can be more easily reduced in size by using a small power source, and the driving time can be markedly reduced using an intermittent driving procedure that corresponds to the conditions of the battery voltage.

Abstract: An electronic device comprising a power source, a piezoelectric actuator A, and a drive control apparatus 100 for controlling the driving of the piezoelectric actuator, wherein the drive control apparatus 100 is provided with a drive circuit 111 for supplying a drive signal SDR to the piezoelectric element of the vibrating body 12, a phase difference detection means 120 for detecting the phase difference indicating the vibration state of the vibrating body 12, a comparison voltage setting circuit 133 for correcting the target phase difference to be the target for the vibration state, and a drive frequency setting means 140 for comparing the phase difference with the target phase difference; and the piezoelectric actuator A can be driven with high efficiency independent of the drive voltage by modifying the drive frequency of the drive signal SDR so that the phase difference approaches the target phase difference based on the results of the above comparison.

Abstract: A drive apparatus for a piezoelectric actuator prevents locking drive frequency in a state of resonance due to harmonics. There is no need to provide external components to filter, and circuitry can easily be reduced in size. The drive apparatus has a phase difference-DC conversion circuit to detect vibrating state of the vibrating body, a comparison circuit, a harmonics detection circuit to detect that the vibrating body is resonating due to harmonics and outputting a harmonics detection signal, an integration circuit to control the frequency of the drive signal supplied to the piezoelectric element of the vibrating body, a variable frequency oscillation circuit, and a drive circuit.

Abstract: A drive device for a piezoelectric actuator, wherein the time needed to achieve highly efficient drive conditions is shortened to reduce power consumption, and stabilized control can be performed. The device has a phase difference detection device (phase difference/voltage conversion circuit (51)) for detecting detection signals of longitudinal oscillation and bending oscillation from an oscillator (5) and detecting the phase difference between these two signals, frequency control devices (52 to 56) for comparing the phase difference detected by the phase difference detection device with a standard phase difference value and controlling the frequency of a drive signal sent to a piezoelectric element (17) on the basis of the results of this comparison, and an amplitude detection device (amplitude detection circuit (57)) for detecting the amplitude of the detection signal of the piezoelectric element (17).

Abstract: A time measurement device includes a power generator 2, secondary power source 31, current time counters 922 and 932, receiver circuit 42 for receiving a time standard radio wave, time display means 5 for displaying the current time, power detector 83 for outputting a power detection signal when the power generator 2 is in a power generating state or when a voltage stored in the secondary power source 31 is at a predetermined voltage value, operation mode switcher 874 switching, in response to the power detection signal, between a power saving mode in which time display is suspended and a standard mode in which time display is not suspended. The operation mode switcher 874 causes the time display means 5 to display the current time based on the time information counted by the time counters 922 and 932 and the time information received by the receiver circuit in response to the device being switched from the power saving mode to the standard mode.

Abstract: A drive apparatus for a piezoelectric actuator prevents locking drive frequency in a state of resonance due to harmonics. There is no need to provide external components to filter, and circuitry can easily be reduced in size. The drive apparatus has a phase difference-DC conversion circuit to detect vibrating state of the vibrating body, a comparison circuit, a harmonics detection circuit to detect that the vibrating body is resonating due to harmonics and outputting a harmonics detection signal, an integration circuit to control the frequency of the drive signal supplied to the piezoelectric element of the vibrating body, a variable frequency oscillation circuit, and a drive circuit.

Abstract: In an electronic device 1 comprising a battery 200 and a piezoelectric actuator A, a power source voltage before drive control is started is maintained by a sample holding circuit 102, a reference voltage is set by a reference voltage generating circuit 103 on the basis of the power source voltage, and a control circuit 106 stops driving when the power source voltage falls below a drive stop voltage as compared by a second comparison circuit 105, and begins driving the piezoelectric actuator A again when the power source voltage exceeds the reference voltage as compared by a first comparison circuit 104. Therefore, the device can be more easily reduced in size by using a small power source, and the driving time can be markedly reduced using an intermittent driving procedure that corresponds to the conditions of the battery voltage.

Abstract: A drive device for a piezoelectric actuator, wherein the time needed to achieve highly efficient drive conditions is shortened to reduce power consumption, and stabilized control can be performed. The device has a phase difference detection device (phase difference/voltage conversion circuit (51)) for detecting detection signals of longitudinal oscillation and bending oscillation from an oscillator (5) and detecting the phase difference between these two signals, frequency control devices (52 to 56) for comparing the phase difference detected by the phase difference detection device with a standard phase difference value and controlling the frequency of a drive signal sent to a piezoelectric element (17) on the basis of the results of this comparison, and an amplitude detection device (amplitude detection circuit (57)) for detecting the amplitude of the detection signal of the piezoelectric element (17).

Abstract: A time measurement device includes a power generator 2, secondary power source 31, current time counters 922 and 932, receiver circuit 42 for receiving a time standard radio wave, time display means 5 for displaying the current time, power detector 83 for outputting a power detection signal when the power generator 2 is in a power generating state or when a voltage stored in the secondary power source 31 is at a predetermined voltage value, operation mode switcher 874 switching, in response to the power detection signal, between a power saving mode in which time display is suspended and a standard mode in which time display is not suspended. The operation mode switcher 874 causes the time display means 5 to display the current time based on the time information counted by the time counters 922 and 932 and the time information received by the receiver circuit in response to the device being switched from the power saving mode to the standard mode.

Abstract: When an electronic timepiece is in a power-saving mode in which the current time display is suspended, it is determined whether or not the charge voltage supplied from a high-capacity capacitor is higher than a predetermined reference voltage, and if higher, enough electrical energy is stored in the high-capacity capacitor to return from the power-saving mode to the display mode, so that a current time restoration process is performed upon detecting power generation. On the other hand, if the charge voltage is less than or equal to the predetermined reference voltage, the supply of the power supply voltage to the control circuits is stopped to prevent the electrical energy stored in the high-capacity capacitor from being consumed needlessly. As a result, the electronic timepiece can be reactivated quickly when the power generating device begins to generate power.

Abstract: If a supply voltage reaches a voltage level that may lead to detection errors of a supply voltage detecting circuit, then a voltage detecting operation is prohibited if generation of power that can be charged into a high-capacity secondary power source is not detected, while the voltage detecting operation is continued if the generation of power that can be charged into the high-capacity secondary power source is detected.

Abstract: An oscillation circuit 80 produces an oscillation signal in accordance with the oscillation frequency of a quartz oscillator 81, and a frequency dividing circuit 90 divides the frequency of the oscillation signal to produce a sampling clock CKs having a duty ratio of 1/8. A constant-voltage circuit 70 is operated during the period in which the sampling clock CKs takes an “H” level, and is stopped during the period in which the sampling clock CKs takes an “L” level. During the period in which the constant-voltage circuit 70 stops the operation, a voltage Vreg affected by fluctuations in a second lower potential side voltage Vss2 is generated. However, since the cycle of the sampling clock CKs is short, a fluctuation width of the voltage Vreg is suppressed. Power consumption of the constant-voltage circuit 70 is reduced.

Abstract: To provide a portable electronic device which is easily shifted into a power save mode at the discretion of an operator, such as a user, and optimally reduces power consumption in accordance with the current use of the device. An operator can force an electronic device into a power save mode at the operator's discretion by manipulating a control. Electrical energy stored is thus reliably saved in accordance with the usage by the operator, and unnecessary power consumption is efficiently reduced, even more than in a method in which a device automatically stops the time display and is shifted into a power save mode in accordance with the presence or absence of power generation. Setting a time limit within which the operational state of the control needs to be complete, the operator is prevented from erroneously shifting into the power save mode, and the ease of use of the time measurement device is still assured.