JPH0636667B2 - Display switching semiconductor switch element control circuit - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention controls a semiconductor switch element provided in a power supply path to a load such as a motor for a washing machine, and a display control for controlling a lighting state of a display associated therewith. The present invention relates to a dual-purpose semiconductor switch element control circuit.

Conventional configuration and its problems As a method of igniting a bidirectional semiconductor switch element that intermittently supplies power to a load such as a motor, a method of near the zero phase of the power supply voltage, direct current ignition, or pulse ignition is conventionally known. However, all of them have the drawback that the ignition circuit is expensive.

Further, in order to turn off the display and stop the power supply to the load when an instantaneous power failure occurs, the instantaneous power failure detection circuit provided outside has conventionally detected the instantaneous power failure. Therefore, there is a problem that the circuit configuration is complicated and expensive.

OBJECT OF THE INVENTION It is an object of the present invention to ignite a semiconductor switching element at a low cost with a simple circuit configuration, light an indicator with a small amount of power consumption, and reduce the burden on the power supply unit. It is an object of the present invention to provide a semiconductor switch element control circuit that also serves as a display control and can perform a simple circuit configuration for detection.

Configuration of the Invention: A semiconductor switch element control circuit also used for display control according to the present invention includes a power supply synchronization pulse generation circuit for generating a power supply synchronization pulse, a clock pulse generation circuit for generating a clock pulse having a frequency higher than the power supply synchronization pulse, and the power supply. A counter that is set / reset by a synchronization pulse to generate an output each time the clock pulse is counted by a certain number, a display that lights according to the output of the counter, and a switch that is fired according to the output of the counter to conduct. And a semiconductor switch element that counts the output of the counter and generates an output when the count value exceeds a predetermined value, and the counter in response to the output of the instantaneous power failure detection counter. And a shutoff means for shutting off the output of the power to the display and the semiconductor switch element. It is the one.

Description of Embodiments FIG. 1 is a circuit diagram of a display control / semiconductor switch element control circuit according to an embodiment of the present invention. Reference numeral ₁ is a power supply synchronization pulse generation circuit that generates a power supply synchronization pulse P ₁ synchronized with a commercial power supply, and 2 is a clock pulse generation circuit that generates a clock pulse P ₂ having a frequency sufficiently higher than the power supply synchronization pulse P ₁ . Reference numeral 3 denotes a storage unit for storing the sequential operation, and the display control terminals T _{11 to} T ₁₃ , depending on the stored contents by inputting the power supply synchronizing pulse P ₁ and the clock pulse P ₂ .
The output states of T _{21 to} T ₂₃ and switch control terminals T _{31 to} T ₃₃ are sequentially changed. 4 is a ternary counter which is set and reset by the power-supply sync pulses P ₁ applied through the storage unit 3 counts the clock pulses P _2, and generates a pulse from the output terminal T ₄₁ through T ₄₃ according to the count value. 5 is a power supply synchronizing pulse P ₁ applied through the storage unit 3.
A counter that is set / reset by and counts pulses from a specific output terminal of the ternary counter 4, for example, T ₄₁ , and is output when the count value exceeds the number of pulses included in one cycle of the power supply synchronization pulse P _1. Changes from high level to low level. Reference numeral 6 is a display control terminal T _{11 to} T of the storage unit 3.
Six AND gates AN _{11 to} AN ₁₃ and AN ₂₁ to which the outputs of ₁₃ · T _{21 to} T ₂₃ are respectively applied to one input terminal and the output of the counter 5 is commonly applied to the other input terminal
A group of gates consisting of AN ₂₃ . In reference numeral 7, the outputs of the switch control terminals T _{31 to} T ₃₃ of the storage unit 3 are applied to the first input terminal and the output pulse of the output terminal T ₄₁ of the ternary counter 4 is applied to the second input terminal in common. AND gate AN ₃₁ to which the output of the counter 5 is commonly applied to the third input terminal
It is a gate group consisting of AN ₃₃ . 8 is Andgate AN ₁₁ ~
The outputs of AN ₁₃ , AN _{21 to} AN ₂₃ are applied to one input terminal respectively, and the pulses from the output terminals T _{41 to} T _{43 of the} ternary counter are applied to the other input terminal. NAND gates NA ₁₁ to NA ₁₃ ,
A gate group consisting of NA _{21 to} NA ₂₃ . 9 and gate
Inverter IN ₁ to which outputs from AN _{31 to} AN ₃₃ are added respectively
~ IN _{3 is} a driver group. 10 is a NAND gate
NA ₁₁ ~NA _13, a display unit group consisting of light emitting diodes LED ₁ ~LED ₆ to light up in response to the output of the NA ₂₁ ~NA _23. 11 is a semiconductor switching element group consisting of bidirectional triode thyristor SCR ₁ ~SCR ₃ are respectively ignition at the output of inverter IN ₁ to IN _3. 12 resistor group consisting of current-limiting resistors R ₁ to R ₆ of the light emitting diodes LED ₁ ~LED _6, 13 is a resistance group composed of the gate resistor R ₇ to R ₉ in the bidirectional triode thyristor SCR ₁ ~SCR _3.

FIG. 2 shows a specific circuit diagram of the power supply synchronization pulse generation circuit 1. In the figure, E is a commercial power source and a transformer T
R is connected. The secondary output of the transformer TR is a resistor R ₁₀ ~
It is divided by R ₁₁ and smoothed by diode D and capacitor C, the divided voltage of resistors R ₁₀ and R ₁₁ is applied to the base of transistor Q, and the voltage across capacitor C is applied to the collector of transistor Q via resistor R _12.・
Applied between emitters. Therefore, the transistor Q
Power supply synchronization pulse P ₁ synchronized with commercial power supply E from the collector of
Will be output.

In FIG. 1, when the portion surrounded by the broken line is composed of a microcomputer, the storage unit 3 is a read only memory, the ternary counter 4 and the counter 5 are soft counters provided in the random access memory, and the gate group 6 is provided. ~
8 can be realized by an internal logic circuit section, a read-only memory and an output port.

Next, the operation will be described in detail with reference to FIGS. 3 and 4. Figure 3 from the power supply synchronization pulse generator 1
A power supply synchronizing pulse P ₁ as shown in (A) is output, the counter 2 is set / reset by this power supply synchronizing pulse P _1, and the clock pulse from the clock pulse generating circuit 2 as shown in FIG. 3 (B). P ₂ is counted, and the output terminals T _{41 to} T _{43 of} the respective count values output 1/3 duty whose phases are sequentially shifted by 1/3 cycle as shown in FIGS. 3 (C), (D), and (E). Output each pulse. By these pulses, the light emitting diodes LED _{1 to} LED ₆ are time-dividedly fed, and are brought into a state in which intermittent lighting can be sequentially performed in 1/3 cycle. Ternary period of the counter 4 at that time, that is, for example Figure 3 cycles of pulses (C) is sufficiently smaller than the period of the power-supply sync pulses P _1, ternary counter in one period of the power-supply sync pulses P ₁ 4 operates multiple times, and each of the light emitting diodes LED _{1 to} LED ₆ is ₁ of the power supply synchronizing pulse P ₁ .
It can be turned on multiple times during the cycle.

On the other hand, the storage unit 3 changes the output states of the display control terminals T _{11 to} T ₁₃ and T _{21 to} T ₂₃ according to the stored contents, and, for example, the output of the display control terminal T ₁₁ is at a high level. At this time, the light emitting diode LED ₁ is intermittently turned on at the timing of the pulse shown in FIG. 3 (C), and similarly, the other display control terminals T ₁₂ , T ₁₃ ,
When any of T _{21 to} T ₂₃ is at a high level, the light emitting diodes LED _{2 to} LFD ₆ are intermittently turned on at any timing of the pulses of FIGS. 3 (C) to (E). It should be noted that even though intermittent lighting is performed, the cycle is extremely short, and therefore it appears to be continuously lighting when viewed with the naked eye.

The storage unit 3 changes the output states of the switch control terminals T _{31 to} T ₃₃ according to the stored contents. For example, when the output of the switch control terminal T ₃₁ is at a high level, the ternary counter 4 is used.
The pulse at the output terminal T ₄₁ of the bidirectional bidirectional 3-terminal thyristor via the AND gate AN ₃₁ , the inverter IN ₁ and the resistor R _7.
Input to the gate of CSR ₁ , bidirectional 3-terminal thyristor SC
R ₁ is pulse fired and becomes conductive. The same applies when the other switch control terminals T ₃₂ and T ₃₃ are at a high level.

However, if the commercial power source E momentarily fails, it will be
The power supply synchronizing pulse P ₁ having a waveform as shown in FIG. 4 (A) does not fall as shown in FIG. 4 (B) and remains in the high level output state. As a result, the ternary counter 4 and the counter 5
Will no longer be set and reset, for example, the output pulse of the terminal T ₄₁ of the ternary counter 4 is continuous over FIG. 4 (C) in one period or more power-supply sync pulses P _1, as shown, the pulse of the output terminal T ₄₁ The counter 5 also counts over one cycle or more, the count value of the counter 5 becomes a certain value or more, and the output changes from the high level state to the low level state. As a result, the outputs of the gate groups 6 and 7 become low level, the control signal from the storage unit 3 is cut off, and the light-emitting diodes LED _{1 to} LED ₆ and the bidirectional 3-terminal thyristors CSR _{1 to} SCR ₃ are energized. Is stopped,
Is bidirectional triode thyristor SCR ₁ ~SCR ₃ blocking with light emitting diodes LED ₁ ~LED ₆ is turned off.

Power supply to a load such as a motor is controlled by the conduction and interruption of the bidirectional triode thyristor SCR ₁ ~SCR _3.

Thus, this embodiment has six light emitting diodes LED ₁
~ LED ₆ can be time-divided power supply, and any _{one of} the light emitting diodes LED _{1 to} LED ₆ is intermittently turned on in response to a control signal from the storage unit 3, so that the light emitting diodes LED _{1 to} LED ₆ The power consumption can be reduced, and the load on the power supply unit can be reduced. Also light emitting diode
A ternary counter 4 for lighting LEDs _{1 to 6} in a time division manner
Output terminal T ₄₁ pulse is bidirectional 3-terminal thyristor SC
Since the firing pulse of R _{1 to} SCR ₃ is used, another firing circuit is unnecessary, the circuit configuration for firing is simplified, and cost reduction can be achieved. Further, since the counter 5 set / reset by the power supply synchronizing pulse P ₁ generates the output when the output of the ternary counter 4 counts a certain value or more, the instantaneous power failure can be detected easily and inexpensively. It is also possible to detect that the width of the power supply synchronization pulse is more than a certain value and consider it as an instantaneous power failure.
The configuration is simple as compared with such a configuration.

In the above embodiment it was used ternary counter 4, n-ary counter according to one the number of the light emitting diodes LED ₁ ~LED ₆ (n is an integer) may be used. Further, in the embodiment, the pulse of the output terminal T ₄₁ of the ternary counter 4 is input to the gate group 7, but the clock pulse P ₂ may be input.

EFFECTS OF THE INVENTION According to the present invention, the display can be intermittently lit to reduce the power consumption of the display to reduce the load on the power supply unit, and the circuit for intermittently illuminating the display can be provided as a semiconductor switch element. It can be commonly used for ignition, a special ignition circuit is not required, the circuit configuration for ignition is simplified, and the cost can be reduced. Moreover, with the configuration that counts the output of the counter with the instantaneous power failure detection counter,
Instantaneous power failure can be detected with a simple and inexpensive configuration.

[Brief description of drawings]

FIG. 1 is a block diagram of a display control / semiconductor switch element control circuit according to an embodiment of the present invention, FIG. 2 is a detailed circuit diagram of its essential parts, FIGS. 3 (A) to (E) and FIG. 4 (A). ) To (C) are waveform charts of the respective parts. 1 ... Power supply synchronization pulse generation circuit, 2 ... Clock pulse generation circuit, 3 ... Storage unit, 4 ... Ternary counter, 5 ...
Counters, 6 to 8 ... Gate group, 10 ... Display group, 1
1 ... Semiconductor switch element group

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sadayuki Tamae 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-58-89064 (JP, A)

Claims (1)

[Claims] 1. A power supply synchronization pulse generation circuit for generating a power supply synchronization pulse, a clock pulse generation circuit for generating a clock pulse having a frequency higher than this power supply synchronization pulse, and the clock pulse set / reset by the power supply synchronization pulse. A counter that generates an output each time a certain number of is counted, and a display that lights according to the output of this counter,
A semiconductor switch element that is ignited in accordance with the output of the counter and becomes conductive, an instantaneous power failure detection counter that counts the output of the counter and generates an output when the count value exceeds a predetermined value, and this instantaneous A display control / semiconductor switch element control circuit, comprising: a shutoff means for shutting off the output of the counter from being supplied to the display and the semiconductor switch element in response to the output of the power failure detection counter.