JPS6330835B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reset circuit device effective for electronic equipment equipped with a remote control circuit.

An electronic device equipped with a remote control circuit usually includes a first power source for a receiving section of the remote control circuit and a second power source for the electronic device itself. The first power source is used to maintain the remote control circuit in a standby state at all times, and the second power source is used to substantially operate the main body of the electronic device.

FIG. 1 shows a remote control circuit section 11,
FIG. 2 is a configuration diagram showing an electronic device main body section 12. FIG. The remote control circuit section 11 includes a first power supply circuit 14, a first reset circuit 15, a first processing circuit 16, etc., and the electronic device main body section 12 includes:
second power supply circuit 17, second reset circuit 18,
It is composed of a second processing circuit 19 and the like. 13
is a plug that is connected to a commercial power source. When this plug is connected to a commercial power source, the remote control circuit section 11 is powered on, and the first reset circuit 15, first processing circuit 16, etc. are powered on. Supplied.

The first processing circuit 16 includes a receiving circuit for remote control. The reset circuits 15 and 18 obtain set and reset outputs, respectively, in response to the rise and fall of the outputs of the corresponding power supply circuits 14 and 17, and set and reset the corresponding processing circuits 16 and 19, respectively. The operating waveforms of these circuits are normally expressed as shown in FIGS. 2a to 2d. It should be noted that all the waveforms shown in FIG. 2 are exaggerated to make the explanation easier to understand. 2a shows the operating waveforms of the first power supply circuit 14, FIG. 2b shows the operating waveforms of the first reset circuit 15, and FIG. 2c shows the operating waveforms of the second power supply circuit 1.
7, the operating waveform of FIG. 2d is the second reset circuit 1.
This is the operating waveform of No. 8. In this operating waveform diagram,
Time t ₁ is when the plug 13 is connected to the commercial power source. When the plug 13 is connected to a commercial power supply, the first power supply circuit 14 becomes stable at time _t2 .
When this becomes stable, the first reset circuit 15
becomes set at time _t3 . The remote control circuit section 11 is now in a standby state.
Can receive remote control signals.

Next, a remote control operation is performed,
When there is a command to turn on the electronic device main body 12, a control signal is supplied from the first processing circuit 16 to the second power supply circuit 17. Now this time t ₄
Then, the second power supply circuit 17 is in a stable state between time _t4 and time _t5 . Once this is stable, the second reset circuit 18 enters the set state at time _t6 . In this state, the electronic device main body 12 can obtain its original function.

Next, when an operation is performed using the remote control to turn off the power on the electronic device main body 12 side, the second power supply circuit 17 is turned off by a control signal from the first processing circuit 16 . When this second power supply circuit 17 is turned off, the output of this circuit decreases to zero as shown at time _t7 to _t9 , but
In the middle of this (time t ₈ ), the second reset circuit 18 enters the reset state. Then, only the remote control circuit section 11 side is placed in a standby state, and the electronic device main body 12 side is turned off. here,
When trying to turn off all power sources, the plug 13 is pulled out from the commercial power source. (Time t ₁₀ ) Then, while the output of the first power supply circuit 14 is falling (Time t ₁₁ ), the second reset circuit 15 enters the reset state. Time _t12 is when the output of the power supply circuit 14 becomes zero.

In the above-mentioned reset means, if the second power supply circuit 17 is on and for some reason, the power cord or the like is connected and the plug 1 is disconnected from the outlet.
If plug 13 is pulled out and plug 13 is inserted into the outlet immediately, plug 1
3 is pulled out and then turned on again after a short period of time, but in this case, the first reset circuit 15 is not reset because the current consumption on the remote control circuit side is generally small and the power supply time constant is large. Therefore, an output from the first processing circuit 16 is generated, and the second power supply circuit 17 is turned on again. In other words, pulling out the plug 13 means turning off all power supplies once, so if the power is turned off once, the remote control circuit section 11
Even though the electronic device main unit 12 must be turned on again after receiving a new remote control signal, it automatically restarts without passing the control command of the remote control signal. This results in a malfunction in which the second power supply circuit 17 is turned on, which is different from the prescribed original power-on procedure.

This invention was made to deal with the above-mentioned situation, and when there is a processing circuit that has first and second power supply circuits and operates on the first and second power supply circuits, the second To provide a reset circuit device capable of preventing malfunction of a processing circuit on the first power supply circuit side by supplying a reset output obtained when a power supply circuit is turned off to the first power supply circuit side. With the goal.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 shows an embodiment of the present invention, and the same parts as in FIG. It has a control means 20 for inputting information to the reset circuit 15 of. In Figure 3, 21
22 is a line that supplies the output power of the power supply circuit 14 to the first reset circuit 15 and the processing circuit 16;
is a line that supplies the output power of the power supply circuit 17 to the second reset circuit 18 and the processing circuit 19.

Figures 4a-d are sequential waveforms of the above device. That is, from time t ₁ to t ₂ , the plug 13 is connected to the commercial power supply and the first power supply circuit 14
This is a period in which the voltage is stabilized, and time _t3 is the timing at which the first reset circuit 15 enters the set state.
After this, when an operation is performed to turn on the power on the electronic device main body 12 side by remote control operation, a control signal is output from the processing circuit 16. Then, as shown from time _t4 to time _t5 , there is a rising period of the second power supply circuit 17. When the output of the second power supply circuit 17 becomes stable, the output state of the second reset circuit 18 becomes the set state.

Next, when a remote control operation is performed to turn off the power on the electronic device main body 12 side, a control signal is generated in the processing circuit 16 and supplied to the second power supply circuit 17 . As a result, the output of the second power supply circuit 17 finally becomes zero after a falling period as shown from time _t7 to _t10 .

Here, while the output of the second power supply circuit 17 is decreasing, a reset output (FIG. 4d) is obtained from the second reset circuit 18 as shown at time _t8 . As a result, the processing circuit 19 on the electronic device main body 12 side is reset, but in the case of the present invention, the reset output is also input to the first reset circuit 15 on the remote control circuit section 11 side. Therefore, this first reset circuit 1
The set output of 5 is as shown in Figure 4b.
During the period shown from _t8 to _t9 , it is inverted to the reset state.

As a result, on the remote control circuit section 11 side, once the electronic device main body 12 side is controlled from the power on state to the off state,
A reset process is performed to the initial state (same as when the plug is plugged into a commercial power source). As this operation start information, the output of the second reset circuit 18 is used, and the set output of the first reset circuit 15 is temporarily switched to the reset output for an appropriate period. Note that the sequential waveform from time t ₁₁ to t ₁₃ is the same as that described in FIG. 2.

As described above, the present invention is characterized in that an output as shown in FIG. 4b is obtained from the first reset circuit 15, and an example of means for obtaining this output is specifically It is constructed as shown in FIG.

The output of the second power supply circuit 17 is a circuit including a resistor R ₁ , a capacitor C ₁ , a resistor R ₂ , and a capacitor C ₃ .
It sets the base bias of transistor Tr ₁ and is also supplied to the collector of transistor Tr ₂ via resistor R ₄ . The output of the first power supply circuit 14 is supplied to the collector of the transistor Tr ₁ via a resistor R ₃ . The collector of transistor Tr ₁ is
It is connected to the base of transistor Tr ₂ , and the emitters of each transistor Tr ₁ and Tr ₂ are grounded.

The collector of the transistor _Tr2 is connected to a buffer circuit 24 via a resistor _R5 , and the output of the buffer circuit 24 is used as the output of the second reset circuit. One electrode of a capacitor C 2 is connected to the connection point between the resistor R ₅ and the input terminal of the buffer circuit 24, and the other electrode of the capacitor C ₂ is connected to the first power supply circuit 14 via a resistor R _{6 .} The buffer circuit 23 is connected to the output terminal of the buffer circuit 23 . The output of this buffer circuit 23 is the first
Used as the output of the reset circuit. Note that the diode D ₁ , D ₂ resistor R ₇ constitutes a protection circuit.

The above circuit operation will be explained. First, the period from time t ₁ to t ₃ shown in FIG. 4 is as follows. Transistor Tr ₁ is turned off and transistor Tr ₂ is turned on. Therefore, capacitor C ₂ is (R ₅ +
It is charged with a time constant of R ₆ )×C ₂ (where R ₅ <<R ₄ , R ₆ ). Then, the voltage at the connection point between the resistor _R6 and the capacitor _C2 gradually increases, and a set output appears at the output of the buffer circuit 23 when it exceeds the threshold level.

Next, the second
When the power supply circuit 17 is turned on, the time shown in Fig. 4
During the period from _t4 to _t6 , the transistor _Tr1 is turned on and the transistor _Tr2 is turned off.
Then, the capacitor _C2 is charged with a time constant of ( _R4 + _R5 )× _C2 , and the potential at the connection point between the resistor _R5 and the capacitor _C2 gradually increases. When the potential at this connection point exceeds the threshold level of the buffer circuit 24, a set output appears at its output.

Next, the second
When _the power supply circuit 17 is turned off, from time t ₇ to t ₁₀ shown in FIG _.
turns on. Therefore, the collector potential of transistor Tr ₂ decreases, and since R ₅ << R ₆ is selected, both terminals of capacitor C ₂ decrease to the ground level, and then gradually resistor R ₆ and capacitor C ₂
The potential at the connection point increases. During this operation period, the buffer circuit 23 has a period in which its input potential is below the threshold level, so a reset pulse from time _t8 to time _t9 shown in FIG. 4b is obtained at its output. In this embodiment, one end of the resistor _R4 was connected to the collector of the transistor _Tr2 , and the other end was connected to the second power supply circuit 17, but the other end of the resistor _R4 was connected to the first power supply circuit. It may be connected to the 14 side.

As described above, the present invention detects the reset output obtained from the second reset circuit on the second power supply circuit side and once switches the set output of the first reset circuit to the reset state. It is possible to provide a reset circuit device that can reliably keep the processing circuit on the side of the first power supply circuit in a reset state and can prevent unnecessary malfunctions when the next remote control operation or the like is performed.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the configuration of an electronic device equipped with a conventional remote control circuit, and Figures 2 a to d are
FIG. 3 is a configuration explanatory diagram showing an embodiment of the present invention. FIGS. 4 a to d are operation waveform diagrams of the device of the present invention. FIG. 5 is an example of the main part of the present invention. FIG. 2 is a circuit diagram showing a specific circuit. 14, 17...first and second power supply circuits, 15,
18...first and second reset circuits, 16, 19
. . . first and second processing circuits, 20 . . . control means.

Claims (1)

[Claims] 1 A first processing circuit driven by a first power supply circuit; when the first power supply circuit is turned on, a set output is applied to the first processing circuit, and when the first power supply circuit is turned off, a set output is applied to the first processing circuit; Therefore, there is a first reset circuit that applies a reset output, a second power supply circuit that is on/off controlled by the output of the first processing circuit, and a second power supply circuit that is driven by the second power supply circuit.
a second reset circuit that applies a set output to the second processing circuit when the second power supply circuit is turned on and a reset output when the second power supply circuit is turned off; A reset circuit device comprising means for temporarily switching the set output of the first reset circuit to the reset output for an appropriate period using the reset output of the second reset circuit.