JPH0449672B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an analog electronic timepiece having a step motor rotation detection circuit.

[Conventional technology]

A block diagram of a conventional analog electronic timepiece circuit is shown in FIG. Further, FIG. 3 is an example of a circuit diagram of a part of the drive circuit 5 and rotation detection circuit 6 shown in FIG. 1, and the simple operation and rotation detection principle will be explained below in order.

In FIG. 3, 10 is a drive circuit, and 11 is a part of a rotation detection circuit.

Below, a brief explanation of the conventional operation will be given in the order of the waveform diagram shown in FIG.

First, from the input terminal 13 shown in FIG.
The waveform shown in FIG. 5B is input to the input terminal 14, the waveform shown in FIG. 5C is input to the input terminal 15, and the waveform shown in FIG. Then, first, the waveforms shown in FIGS. 5a and 5b cause the transistor 1 shown in FIG.
7 and 18 are turned on, and current flows in the direction of A to the step motor 19. After a short period of time has elapsed after the step motor is driven, the transistors 20 and 21 are alternately turned on while the transistor 18 remains on to detect rotation.

After that, if it is determined that the rotation is not rotating through this rotation detection, a re-driving pulse as shown by the dotted line is immediately applied. Of course, if it is determined that there is rotation, no re-driving pulse is applied. When these series of operations are completed, the waveform shown in FIG. 5a is input to the input terminal 22, and the waveform shown in FIG.
5, the waveform shown in FIG. 5c is input to the input terminal 23, and the waveform shown in FIG.
The waveform of is inputted to the input terminal 14, and the same operation is performed. In this case, it goes without saying that the direction of the current flowing through the step motor 19 will be in the direction (b).

Repeat the above operation every second of the clock movement (for example, every second if the watch has a one-second movement),
Operate at regular intervals.

[Problem to be solved by the invention]

However, conventional electronic watches have had the following problems.

For example, when assembled as a clock (that is, the step motor 19 has a drive circuit 10 and six transistors 17, 18 for rotation 11 on both ends of the step motor 19,
20, 21, 24, 25 are connected)
If it is desired to measure the performance of the step motor as a single unit, the only way is to apply an alternating voltage as shown in FIG. 6 to both ends of the step motor 19 from the outside. However, the six transistors 17, 18, 20, 2 of the drive circuit and rotation detection circuit
If 1, 24, and 25 are in a floating state and the alternating voltage is applied, the potential of each gate is not fixed, so the current that flows will turn on one of the transistors, and furthermore, the parasitic effects peculiar to transistors will occur. It has been found through experiments that the diode effect also has an effect, and a current bypass circuit other than the step motor 19 is created, making it impossible to accurately measure the various characteristics of the step motor, such as current consumption. In other words, when actually performing these measurements, it is necessary to go through the process of removing the circuit block, applying the alternating voltage to the step motor, measuring various performances, and then reinstalling the circuit block. It's extremely inconvenient and inefficient.

There is also a method of measuring the characteristics of a step motor with a circuit block attached, but with this method, even if you try to measure only the characteristics of the step motor, the characteristics of the circuit block will be involved, so you cannot measure the characteristics of a pure step motor as a single unit. The problem was that it was not possible to measure

SUMMARY OF THE INVENTION In order to solve these conventional problems, the purpose of the present invention is to provide an analog electronic timepiece with a step motor, in which the performance of the step motor can be measured in the assembled state of the timepiece. .

[Means to solve the problem]

In order to solve the above problems, the present invention has a configuration including a control signal generation circuit that turns off a plurality of transistors of a drive circuit that causes current to flow through a step motor and a plurality of transistors of a rotation detection circuit that detects rotation of the step motor. This makes it possible to measure the performance of a step motor while assembled as an electronic clock.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

A block diagram of a circuit for an analog electronic timepiece according to the present invention is shown in FIG. 2, and a simple operating principle of the block diagram shown in FIG. 2 will be described below using the circuit diagram shown in FIG. 4.

This is a method in which a waveform as shown in FIG. 7 is input to the input terminal 27 before inputting the voltage waveform shown in FIG. 6 to both ends of the step motor 26 to measure the performance of the step motor 26. be. Then, after time t in the figure has elapsed, all the transistors 28 to 33 connected between the step motor 26 and the power source are turned off. (This is because the P-channel transistor receives a high level, and the N-channel transistor receives a low level via the inverter 34.) After setting the transistor in this state, the voltage is deformed as shown in FIG. is input to both ends of the step motor and various performance measurements are performed. In this way, the six transistors 28 to 33 connected to both ends of the step motor 26 are forced by the gate input signal.
Since it is turned OFF, the characteristics of the step motor as a single unit can be accurately measured without creating a current bypass circuit as described above. This fact has already been confirmed through experiments. However, if you want to accurately measure the above characteristics in the assembled state of a watch, you can install one input terminal outside the IC and connect it to the seventh input terminal without removing or attaching the circuit block. By inputting a control signal as shown in the figure, this can be done simply by maintaining the above state (all transistors OFF).
Note that providing one input terminal outside the IC results in only a slight increase in size when viewed from the overall IC configuration.

〔Effect of the invention〕

As described above, the present invention provides an electronic timepiece including a drive circuit having a plurality of transistors, a rotation detection circuit having a plurality of transistors, and a plurality of transistors of the drive circuit and a plurality of transistors of the rotation detection circuit in an OFF state. Since the present invention has a configuration including a control signal generation circuit for controlling the operation of the control signal generation circuit and an input terminal for inputting an external signal for controlling the operation of the control signal generation circuit, the following effects can be obtained.

After assembling the watch body, the performance of the step motor can be measured without removing the circuit block.

Measurement data of the performance of the step motor is not affected by the characteristics of the drive circuit, rotation detection circuit, etc., so the measurement accuracy is good.

It becomes possible to measure the performance of a step motor for a watch in which a circuit block and a coil block are integrally formed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional analog electronic timepiece circuit, and FIG. 2 is a block diagram of an analog electronic timepiece circuit according to the present invention. Further, FIG. 3 is a circuit diagram for a conventional electronic timepiece, and FIG. 4 shows an example of a circuit diagram for an electronic timepiece according to the present invention. Furthermore, FIG. 5 is a diagram showing drive and rotation detection waveforms applied to the gates of each transistor in FIGS. 3 and 4, and FIG. 6 is a diagram showing voltage waveforms applied to both ends of the step motor in FIGS. 3 and 4. , and FIG. 7 is a diagram showing control signals according to the present invention. DESCRIPTION OF SYMBOLS 1... Power supply, 2... Oscillation circuit, 3... Frequency division circuit, 4... Waveform synthesis circuit, 5... Drive circuit, 6...
... Rotation detection circuit, 7 ... Control circuit, 8 ... Step motor, 9 ... Control signal generation circuit, 10, 36
... Drive circuit, 11, 37 ... Rotation detection circuit, 3
8...Control signal generation circuit, 13, 14, 15, 1
6, 22, 23, 39, 40, 41, 42, 4
3, 44...Input terminal, 17, 18, 20, 2
1, 24, 25, 28, 29, 30, 31, 3
2, 33... Transistor, 19, 26... Step motor, 34... Inverter, 45, 46...
...OR gate, 47,48,49,50...AND gate, 35,51...Rotation detection resistor.

Claims (1)

[Scope of Claims] 1. A power source, a step motor, an oscillation circuit, a frequency dividing circuit that inputs the output of the oscillation circuit and divides the frequency, and an output of the frequency divider circuit that inputs the output and outputs a composite drive pulse. a waveform synthesis circuit connected to terminals at both ends of the step motor; a drive circuit having a plurality of transistors connected to terminals at both ends of the step motor to flow current to the step motor according to the drive pulse; a rotation detection circuit having a plurality of transistors that detect rotation of the motor; a control signal generation circuit that turns off all transistors connected between terminals at both ends of the step motor and the power supply; and the control signal An electronic timepiece characterized by having an input terminal for inputting an external signal for controlling the operation of a generating circuit.