JPS63276320A - Reset circuit - Google Patents

Abstract

PURPOSE:To decrease a power terminal voltage of an IC circuit rapidly to a threshold voltage or below by providing a detection means detecting the presence or absence of the loading of a battery and a discharge means discharging the electric charge of an internal circuit by an output of the detection means. CONSTITUTION:In loading a battery 3 to a battery box 2 in a reset circuit sending the voltage of the battery 3 and generating an initial value setting signal to an IC circuit 1, the voltage of the battery 3 is fed to a power terminal of the IC circuit 1. Then the voltage of the battery 3 is impressed to the input terminal of an inverter 5 in the inside of the IC circuit 1 and the initial value setting signal AC is outputted from the inverter 5. In removing the battery 3 from the battery box 2, a moving button 6 is moved in the direction A of arrow by a restoring force of a spring 9, contacts 8, 9 as charging means are connected and the charge stored in the capacitance in the IC circuit 1 and the charge in the capacitor 10 connected in parallel with the battery are discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reset circuit, and particularly to a reset circuit used in equipment that uses batteries as a power source.

[Conventional technology]

Conventionally, in a reset circuit for a device that uses a battery as a power source, as shown in FIG. By applying the voltage to the input terminal of the inverter 5 in the ICI through the capacitor 4, an initial value setting operation is performed when the power of the ICI is turned on.

That is, when the battery 3 is connected, a voltage is applied to the power terminal of the ICI as shown by the solid line A in FIG. As shown by the solid line B, a delayed rising voltage is applied.

As a result, the output terminal of the inverter 5 is as shown in FIG. 4(b).
As shown in FIG. 2, a high-level initial value setting signal AC is output from the time the battery is connected until the input voltage of the inverter 5 exceeds the threshold voltage of the inverter 5. The counter, RAM, etc. in the ICI are reset by the initial value setting signal AC.

[Problem that the invention seeks to solve]

In the conventional reset circuit described above, there is no means for discharging the charge on the IC when the battery as a power supply is disconnected.
If the capacitance of the inverter itself or the capacitance connected between the power supply terminals is large, it will take time for the potential of the charged charge to drop below the threshold voltage of the inverter, so as shown by the solid line C in Figure 5 (a), If the battery is connected again before the potential of the charged charge falls below the threshold voltage, as shown in Figure 5(b), the initial value setting signal shown by the broken line is not generated and the internal There is a problem that counters and RAM cannot be set to initial values.

[Means for solving problems]

The reset circuit of the present invention detects the voltage of a battery used as a power source and generates an initial value setting signal to an internal circuit of a device, and includes a detection means for detecting whether or not the battery is attached, and a detection means for detecting whether or not the battery is attached. and discharging means for discharging the charge in the internal circuit by output.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of a first embodiment of the present invention.

As shown in FIG. 1, when the battery 3 is inserted into the battery box 2, the voltage of the battery 3 is supplied to the power terminal of the ICI, which is the internal circuit of the device, and the voltage of the battery 3 is supplied to the ICI power supply terminal through the capacitor 4.
The initial value setting signal AC is applied to the input terminal of the inverter 5 in the inverter 5, and the initial value setting signal AC is output from the inverter 5 as described above.

When the battery 3 is removed from the battery box 2, the movable button 6 as the detection means moves in the direction of the arrow A by the restoring force of the spring 9, and the contact pieces 8 and 9 as the charging means are connected.
The charge accumulated in the capacitor in the CI and the charge in the capacitor 10 inserted in parallel with the battery are discharged.

In this way, by short-circuiting or opening the power supply terminal of the ICI depending on the presence or absence of the battery 3, even if the battery is replaced in a short time, the charge accumulated in the ICI can be rapidly discharged and the potential can be lowered. can be done.

FIG. 2 is a sectional view of a battery box used in a second embodiment of the present invention.

As shown in FIG. 2, one electrode 12 of the battery box 11
A spring 13 and a contact portion 14 are incorporated in the spring 13 and the contact portion 14 .

The contact portion 14 is not electrically connected to the electrode 12 when the battery is inserted, and is electrically conductive when the battery is removed.

According to the second embodiment, since the detection means and the discharge means are incorporated into the battery box, there is an advantage that the circuit can be miniaturized.

[Effects of the Invention] As explained above, the reset circuit of the present invention includes a detection means for detecting whether or not a battery is attached, and an I/O when the battery is removed.
By adding a discharging means to rapidly release the charge accumulated in the capacitor connected between the power supply terminals or the power supply terminals, the I
Since the voltage between the power supply terminals of the IC can be rapidly lowered to below the threshold voltage, the initial value setting signal is output even when the battery is reinserted after a short period of time, ensuring that the internal circuit of the IC returns to the initial value. This has the effect of being configurable.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention, FIG. 2 is a sectional view of a battery box used in the second embodiment of the present invention,
Figure 3 is a block diagram of an example of a conventional reset circuit, and Figure 4 is a block diagram of an example of a conventional reset circuit.
In the figures, (a) and (b) are timing diagrams of the voltage applied to the IC and the output voltage of the inverter, respectively, to explain the operation of the reset circuit in Figure 3 when a battery is connected, and Figure 5.
a'>- and (b) are timing diagrams of the IC power supply voltage and the inverter output voltage, respectively, for explaining the operation of the reset circuit of FIG. 3 during battery replacement. 1...IC52...Battery box, 3...Battery,
4... Capacitor, 5... Inverter, 6... Movable button, 7.8... Contact piece, 9... Spring,
1o river capacitor, 11... battery box, 12...
- Electrode, 13... Spring, 14... Contact part. Agent Patent Attorney Susumu Uchihara 15.1gu “No 1 Suge Song 152 Fig. 4 (Ka

Claims (1)

[Claims] In the reset circuit that detects the voltage of the battery used as a power source and generates an initial value setting signal to the internal circuit of the device,
A reset circuit comprising: a detection means for detecting whether or not the battery is attached; and a discharge means for discharging the charge in the internal circuit based on the output of the detection means.