JPWO2012117472A1 - Input circuit and integrated circuit of the input circuit - Google Patents

Abstract

An input circuit corresponding to NPN open collector control, PNP open collector control, and relay control and suppressing power consumption and an integrated circuit of the input circuit are provided. In the input circuit 100 according to the present invention, the anode of the diode D1 is connected to the input terminal IN, one end side of the resistor R1 is connected to the cathode side of the diode D1, and one end side of the resistor R2 is connected to the other end side of the resistor R1. One end of the resistor R3 is connected to the other end of the resistor R2, the other end of the resistor R3 is grounded, the other end of the resistor R2, and the anode of the diode D2 is connected to one end of the resistor R3, and the diode D2 Is connected to the input terminal IN, the cathode of the diode D3 is connected to one end of the resistor R1, the internal power supply terminal V2in is provided to the anode of the diode D3, and the light emitting element HD is connected in parallel with the resistor R1. The light receiving element PD is connected to face the light emitting element HD.

Description

  The present invention relates to an input circuit corresponding to various signal systems of a control device and an integrated circuit of the input circuit.

  Conventionally, three types of signals such as NPN open collector control, PNP open collector control, and relay control have been used as various signals of a control device such as a PLC (programmable logic controller).

  Patent Document 1 discloses an input circuit in which an NPN switching element and a PNP switching element are mixed and connected simultaneously.

  In the input circuit described in Patent Document 1, an AC input is applied to the first external terminal to which the switching element can be connected, the first resistor and the second resistor, and the first input terminal and the second input terminal. The first input terminal is connected to the first external terminal, and the second input terminal is connected to one polarity part of the power supply part via the first resistor. And connected to the other polar part of the power supply part via the second resistor.

  Patent Document 2 discloses a control board that can easily cope with a case where the specifications of a terminal block such as a screw terminal and a thrust terminal are different, and obtain a control board with good workability.

  In the control board described in Patent Document 2, a control board, a control board for mounting the control section, a control board having a connector, a control board having a connector, a terminal block, a sink specification or a source specification are provided. A detachable terminal block board having a connector, and a detachable terminal block board having a connector, and a control board connector and the detachable terminal block board connector connected to each other It is composed.

  Patent Document 3 includes a storage unit that stores the determination result determined by the determination unit during the previous operation, and the determination result stored in the storage unit and the determination result determined during the current operation by the determination unit. And a comparison means for comparing the difference between the determination result of the previous operation and the determination result of the current operation when it is determined that the determination result is different. An interface circuit that can reduce the manufacturing cost and prevent the occurrence of erroneous operation as much as possible while disclosing the configuration of any of the source inputs is disclosed.

  In the interface circuit described in Patent Document 3, in an interface circuit having an input terminal for capturing an input signal such as a contact input or logic, a connection state in which a pull-up resistor is connected to the input terminal and a connection state in which a pull-down resistor is connected Switching means for switching, determination means for determining whether the switching connection state of the switching means is a sink input or a source input, and a signal obtained by inverting the input signal based on the determination result of the determination means The signal switching means for switching between the signal output state for outputting the signal and the signal output state for outputting the input signal as it is, the storage means for storing the determination result determined at the previous operation by the determination means, and the storage means Comparison means for comparing the discrimination result determined by the discrimination means with the discrimination means during the current driving, In which the result and the determination result of the present operation is different is a notification means for notifying the difference when it is determined.

JP 2005-143002 A JP 2005-142595 A Japanese Patent No. 3557335

As described above, Patent Document 1 has a problem that power consumption during standby is increased because control of the current flowing through the photocoupler is performed mainly on the resistance.
In any of Patent Documents 1 to 3, there are documents that can be considered for NPN open collector control and PNP open collector control, but relay control is not supported. In particular, Patent Document 3 has a problem that a switch is required and the switch needs to be mounted, which is expensive in terms of manufacturing cost. In addition, when the switch is mounted, there is a fear that a manufacturing cost (manufacturing man-hour) and solder scraps are generated.

  An object of the present invention is to provide an input circuit corresponding to NPN open collector control, PNP open collector control, and relay control and suppressing power consumption, and an integrated circuit of the input circuit.

(1)
An input circuit according to one aspect is an input circuit for supplying a signal input from a control device via an input terminal to a control target device, and capable of AC input from the input terminal via a first resistor. And a first circuit connected to the power supply unit via the first diode, a photocoupler from the input terminal via the first resistor, and a second circuit grounded via the Zener diode. is there.

In the input circuit, when an NPN open collector output or relay output is connected to the input terminal, the NPN open connected to the input terminal from the internal power supply applied to the internal power supply terminal via the first diode, photocoupler, and first resistor A current can be passed to the GND side of the collector output or the relay output.
Further, when a PNP open collector output is connected to the input terminal, a current can flow from the external power source applied to the input terminal in the order of the first resistor, the photocoupler, the Zener diode, and the ground.
As a result, the input circuit can cope with any of the PNP open collector output, the NPN open collector output, and the relay output, and can further reduce power consumption during standby.
Moreover, since the number of parts can be minimized, an increase in manufacturing cost can be suppressed.

(2)
In the input circuit, a second resistor is inserted between the photocoupler and the first diode of the first circuit, and a third resistor is inserted between the photocoupler and the zener diode of the second circuit.

  By inserting the second resistor and the third resistor, the current can be easily adjusted.

(3)
In the input circuit, the first diode is a Zener diode.

By using a Zener diode, a current can be flowed at a constant voltage, so that current adjustment becomes easy.

(4)
An input circuit according to still another aspect is an input circuit for supplying a signal input from a control device via an input terminal to a control target device, and an anode of a fourth diode is connected to the input terminal side, One end of the fourth resistor is connected to the cathode side of the diode, one end of the fifth resistor is connected to the other end of the fourth resistor, one end of the sixth resistor is connected to the other end of the fifth resistor, The other end side of the resistor is grounded, the other end side of the fifth resistor, the anode of the fifth diode is connected to one end side of the sixth resistor, the cathode of the fifth diode is connected to the input terminal side, and the fourth The cathode of the sixth diode is connected to one end of the resistor, the internal power supply terminal is provided on the anode side of the sixth diode, the light emitting element is connected in parallel with the fourth resistor, and the light receiving element is opposed to the light emitting element. It is connected.

In the input circuit, when an NPN open collector output or a relay output is connected to the input terminal, the NPN connected to the sixth diode, the light emitting element, the fifth resistor, the fifth diode, and the input terminal from the internal power supply applied to the internal power supply terminal. A current can be passed to the GND side of the open collector output or the relay output.
In addition, when a PNP open collector output is connected to the input terminal, a current is allowed to flow from the external power supply applied to the input terminal in the order of the fourth diode, light emitting element or fourth resistor, fifth resistor, sixth resistor, and ground. it can.
As a result, the input circuit can cope with any of the PNP open collector output, the NPN open collector output, and the relay output, and can further reduce power consumption during standby.

(5)
In the input circuit, the resistance value of the fifth resistor may be lower than the resistance value of the sixth resistor.

  When an NPN open collector output or a relay output is connected to the input terminal, current can be prevented from flowing through the sixth resistor, and the voltage across the fourth resistor can satisfy the forward voltage of the light emitting element. As a result, the secondary circuit of the light receiving element can be turned on.

(6)
In the input circuit, the fourth resistor may have a resistance value that prevents at least a current from flowing through the light emitting element when an input signal to the input terminal is not input.

  In this case, since the resistance value of the fourth resistor is set so that no current flows to the light emitting element when no input signal is input to the input terminal, the secondary side circuit (light receiving element) is in a standby state of the input circuit. Can be turned off, and power consumption during standby can be suppressed.

(7)
The input circuit may further include an internal power supply applied to the internal power supply terminal, and the internal power supply may have a lower voltage than an external power supply in the control device.

  In this case, since the internal power supply is set at a voltage lower than that of the external power supply of the control device, a larger current can flow through the fourth resistor than when no input signal is input, and the current flows through the light emitting element. The secondary circuit (light receiving element) can be turned on.

(8)
An integrated circuit according to another aspect is obtained by integrating one or a plurality of input circuits according to any one of claims 1 to 7 into an element.

  In this case, since the input circuit corresponding to all of the PNP open collector output, the NPN open collector output, or the relay output is integrated into an element, it can be used as a single component with a small space. Further, when a plurality of input circuits are integrated and formed into a device, a common internal power supply terminal can be used, and the cost can be reduced.

It is a schematic diagram which shows an example of the input circuit which concerns on the 1st Embodiment of this invention. It is a schematic diagram which shows an example of the input circuit which concerns on the 2nd Embodiment of this invention. It is a schematic diagram which shows an example of the input circuit which concerns on the 3rd Embodiment of this invention. It is a schematic diagram which shows an example of the input circuit which concerns on the 2nd Embodiment of this invention. FIG. 5 is a schematic diagram illustrating another example of the input circuit in FIG. 4. It is a schematic diagram for demonstrating the indicator lamp containing the input circuit which concerns on this invention. It is a schematic diagram for demonstrating the indicator lamp containing the input circuit which concerns on this invention. It is a schematic diagram for demonstrating the case where several input circuits are integrated. It is a schematic diagram for demonstrating the audio | voice output system containing the input circuit which concerns on this invention. It is a schematic diagram for demonstrating the audio | voice output system containing the input circuit which concerns on this invention.

100, 101, ..., 105 Input circuit 110 Integrated circuit IN Input terminal C Capacitor D1, D2, D3 Diode HD Light emitting element PD Light receiving element R1, R2, R3 Resistor V2in Internal power supply terminal

  Embodiments according to the present invention will be described below with reference to the drawings. In the present embodiment, description will be given while showing an example of an input circuit.

(First embodiment)
FIG. 1 is a schematic diagram showing an example of an input circuit 100 according to the first embodiment of the present invention.

  As shown in FIG. 1, an input circuit 100 mainly includes an input terminal IN, output terminals OUT1 and OUT2, a diode D1, a Zener diode ZD1, resistors R1 and R2, a photocoupler PC capable of AC input, an internal power supply terminal V2in, and a capacitor. C.

In the input circuit 100 of FIG. 1, one end of a resistor R1 is connected to the input terminal IN side, and one end of a photocoupler PC capable of AC input is connected to the other end of the resistor R1. The cathode side of the diode D1 is connected to the other end side of the photocoupler PC capable of AC input, and the internal power supply terminal V2in is provided on the anode side of the diode D1.
Further, the cathode side of the Zener diode ZD1 is connected to the other end side of the photocoupler PC capable of AC input, and the anode side of the Zener diode ZD1 is grounded (GND).
A resistor R2 and a capacitor C are provided in parallel with the photocoupler PC capable of AC input. Output terminals OUT1 and OUT2 are provided at both ends of the light receiving terminal. A secondary circuit (not shown) outside the input circuit 100 is connected to the output terminals OUT1 and OUT2.

Next, design conditions for each parameter of the input circuit 100 will be described.
In the input circuit 100 of FIG. 1, the external power supply V1 and the internal power supply V2 are designed to have a relationship of internal power supply V2 <external power supply V1. This is important for ON / OFF control of the photocoupler PC, and the Zener voltage VZ1 of the Zener diode ZD1 is smaller than the external power supply V1 and larger than the internal power supply V2.
That is, when the PNP open collector output is connected to the input terminal IN, since the external power supply V1 is larger than the Zener voltage VZ1 of the Zener diode ZD1, a current flows through the photocoupler PC, and the photocoupler PC is turned on. On the other hand, when the NPN open collector output is connected to the input terminal IN, since the internal power supply V2 is smaller than the Zener voltage VZ1 of the Zener diode ZD1, no current flows through the Zener diode ZD1, and current flows through the photocoupler PC. PC turns on. When neither the PNP open collector output nor the NPN open collector output is connected to the input terminal IN, no current flows through the photocoupler PC, and the photocoupler PC maintains the OFF state.
When the PNP open collector output is connected to the input terminal IN, the forward voltage VFP is applied to the photocoupler PC, the Zener voltage VZ1 is applied to the Zener diode ZD1, and the NPN open collector output is connected to the input terminal IN. The resistor R1 has such a resistance value that the forward voltage VFP is applied to the photocoupler PC.

  In this embodiment, the NPN open collector output is applied to the input terminal IN because of the relationship among the internal power supply V2, the forward voltage Vfd of the diode D1, the forward voltage Vfp of the photocoupler PC, and the resistors R1 and R2. When connected, the primary current Ifpmin for turning on the photocoupler PC is designed to satisfy {(V2−Vfd−Vfp) / R1} − (Vfp / R2)> Ifpmin.

  Further, when the PNP open collector output is connected to the input terminal IN due to the relationship between the external power supply V1, the Zener voltage Vz1 of the Zener diode ZD1, the forward voltage Vfp of the photocoupler PC, and the resistors R1 and R2, the photo The primary current Ifpmin for turning on the coupler PC is designed to satisfy {(V1−Vfp−Vz1) / (R2)} − (Vfp / R1)> Ifpmin.

  Specific examples will be given according to the above conditions. For example, when the external power supply V1 is 24 volts (V), the internal power supply V2 is set to 5 volts (V).

  The resistor R1 is set to 820 ohms (Ω), and the resistor R2 is set to 4.7 kiloohms (kΩ).

(When input signal is OFF)
When an input signal is not applied to the input terminal IN, in the input circuit 100, since the resistor R1 is in an open state, no voltage is applied to the photocoupler PC, and the photocoupler PC is not turned ON. Also, no current flows from the internal power supply V2 to the GND side due to the action of the Zener diode ZD1.

(In case of NPN open collector output or relay output connection)
As shown in FIG. 1, when an NPN open collector output or a relay output is connected to the input terminal IN, in the input circuit 100, the internal power supply V2, the diode D1, the photocoupler PC and the resistor R2, the resistor R1, and the external A current flows through the GND path of the voltage V1. Further, when the NPN open collector is operated by a leakage current, the photocoupler PC is turned on due to the influence, and the resistance value of the resistor R2 is set so that the secondary side circuit is not turned on.

(PNP open collector output connection)
As shown in FIG. 1, when a PNP open collector output is connected to the input terminal IN, the input circuit 100 includes an external power supply V1, a resistor R1, a photocoupler PC and a resistor R2, a Zener diode ZD1, and an internal voltage GND. Current flows along the route.
The Zener diode ZD1 does not operate at the internal voltage V2. However, the Zener voltage VZ1 is set to be sufficiently smaller than the external voltage V1, and the Zener diode ZD1 has a current flowing toward the GND of the internal voltage V2 by the external voltage V1. Flowing. At this time, the forward voltage Vfp of the photocoupler PC is satisfied, and the secondary side circuit is turned on.

As described above, as shown in FIG. 1, the input circuit 100 can handle any of PNP open collector output, NPN open collector output, and relay output.
Further, the current output from the secondary side of the photocoupler PC is unidirectional regardless of which of the PNP open collector output, the NPN open collector output, and the relay output is connected.
Note that all of the NPN open collector output, PNP open collector output, and relay output shown in FIG. 1 are machine tools, production line sensors, sequencers (PLCs, etc.), car wash machines, elevators, escalators, and other control devices. A light emitting device having a secondary circuit, a signal indicator lamp, a lighting device, a sound notification device, an information display device (LED, dot matrix display) ), An arbitrary device such as an interface converter and a communication converter is connected.

(Other examples)
FIG. 2 is a schematic diagram showing another example of the input circuit of FIG. Hereinafter, differences between the input circuit 100 of FIG. 2 and the input circuit 100 of FIG. 1 will be described.

  As shown in FIG. 2, the input circuit 100 includes a Zener diode ZD2 instead of the diode D1 of the input circuit 100 of FIG.

Next, design conditions for each parameter of the input circuit 100 will be described.
In the input circuit 100 of FIG. 2, unlike the input circuit of FIG. 1, the external power supply V1 and the internal power supply V2 are designed to have a relationship of internal power supply V2 ≦ external power supply V1.
In order to make the standby current as close as possible to 0 (standby current≈0), the relationship between the internal power supply V2, the Zener voltage Vz1 of the Zener diode ZD1, and the Zener voltage Vz2 of the Zener diode ZD2 is as follows: Internal voltage V2> Vz1 + Vz2 It becomes a condition. Further, when the relationship of internal power supply V2 = external power supply V1 is satisfied, the relationship between the Zener voltage Vz1 of the Zener diode ZD1 and the Zener voltage Vz2 of the Zener diode ZD2 is preferably the same. For example, even if the internal voltage is 5V or 12V, the above condition is satisfied if the Zener voltage is about 7V.

  In the present embodiment, the NPN open collector output is applied to the input terminal IN because of the relationship between the internal power supply V2, the Zener voltage Vz2 of the Zener diode ZD2, the forward voltage Vfp of the photocoupler PC, and the resistors R1 and R2. When connected, the primary current Ifpmin for turning on the photocoupler PC is designed to satisfy {(V2-Vz2-Vfp) / R1}-(Vfp / R2)> Ifpmin.

  Further, when the PNP open collector output is connected to the input terminal IN due to the relationship between the external power supply V1, the Zener voltage Vz1 of the Zener diode ZD1, the forward voltage Vfp of the photocoupler PC, and the resistors R1 and R2, the photo The primary current Ifpmin for turning on the coupler PC is designed to satisfy {(V1−Vfp−Vz1) / (R2)} − (Vfp / R1)> Ifpmin.

  As a result, the input circuit 100 illustrated in FIG. 2 can perform the same operation as the input circuit 100 illustrated in FIG.

(Still other examples)
FIG. 3 is a schematic diagram showing still another example of the input circuit of FIG. Hereinafter, differences between the input circuit 100 of FIG. 3 and the input circuit 100 of FIG. 1 will be described.

  As shown in FIG. 3, the input circuit 100 is provided with a resistor R3 between the diode D1 of the input circuit 100 of FIG. 1 and the photocoupler PC, so that the Zener diode ZD1 and the photocoupler PC of the input circuit 100 of FIG. A resistor R4 is provided between them.

Next, design conditions for each parameter of the input circuit 100 will be described.
In the input circuit 100 of FIG. 3, as in the input circuit of FIG. 1, the external power supply V1 and the internal power supply V2 are designed to have a relationship of internal power supply V2 <external power supply V1.

  In this embodiment, the NPN open collector output is connected to the input terminal IN from the relationship among the internal power supply V2, the forward voltage Vfd of the diode D1, the forward voltage Vfp of the photocoupler PC, and the resistors R1, R2, and R3. , The primary current Ifpmin for turning on the photocoupler PC is designed to satisfy {(V2−Vfd−Vfp) / (R1 + R3)} − (Vfp / R2)> Ifpmin.

  Further, when the PNP open collector output is connected to the input terminal IN due to the relationship among the external power supply V1, the Zener voltage Vz1 of the Zener diode ZD1, the forward voltage Vfp of the photocoupler PC, and the resistors R1, R2, and R4. The primary current Ifpmin for turning on the photocoupler PC is designed such that Ifpmin satisfies {(V1−Vfp−Vz1) / (R1 + R4)} − (Vfp / R2)> Ifpmin.

  As a result, the input circuit 100 illustrated in FIG. 3 can perform the same operation as the input circuit 100 illustrated in FIG.

(Second Embodiment)
Next, FIG. 4 is a schematic diagram showing an example of the input circuit 100 according to the second embodiment of the present invention.

  As shown in FIG. 4, the input circuit 100 mainly includes an input terminal IN, output terminals OUT1 and OUT2, diodes D1, D2, and D3, resistors R1, R2, and R3, a photocoupler PC, an internal power supply terminal V2in, and a capacitor C. Become.

  In the input circuit 100 of FIG. 4, the anode of the diode D1 is connected to the input terminal IN side, and one end side of the resistor R1 is connected to the cathode side of the diode D1. One end of the resistor R2 is connected to the other end of the resistor R1, the one end of the resistor R3 is connected to the other end of the resistor R2, and the other end of the resistor R3 is grounded (GND).

  The anode of the diode D2 is connected between the resistor R2 and the resistor R3, and the cathode of the diode D2 is connected to the input terminal IN side. The cathode of the diode D3 is connected to one end side of the resistor R1, and the internal power supply terminal V2in is provided on the anode side of the diode D3.

  A capacitor C and a photocoupler PC are provided in parallel with the resistor R1. The photocoupler PC includes a light emitting element HD and a light receiving element PD provided to face the light emitting element HD. Output terminals OUT1 and OUT2 are provided at both ends of the light receiving terminal PD. A secondary circuit (not shown) outside the input circuit 100 is connected to the output terminals OUT1 and OUT2.

Next, design conditions for each parameter of the input circuit 100 will be described.
In the input circuit 100 of FIG. 4, the external power supply V1 and the internal power supply V2 are designed to have a relationship of internal power supply V2 <external power supply V1. This is because the voltage across the resistor R1 satisfies the forward voltage Vfp of the photocoupler PC when the PNP open collector output is connected to the input terminal IN.

  In the present embodiment, the diodes D1, D2, and D3 are the same. Here, from the relationship between the forward voltage Vfd of the internal power supply V2 and the diodes D1, D2, and D3 and the resistors R1, R2, and R3, any output signal of the PNP open collector output, the NPN open collector output, and the relay output In consideration of the case where the photocoupler PC is not input to the input terminal IN, the primary side voltage Vfpmin for turning off the photocoupler PC is designed to satisfy (V2−Vfd) × R1 / (R1 + R2 + R3) <Vfpmin.

  Also, the NPN open collector output is connected to the input terminal IN because of the relationship among the internal power supply V2, the forward voltage Vfd of the diodes D1, D2, and D3, the forward voltage Vfp of the photocoupler PC, and the resistors R1 and R2. In this case, the primary side current Ifpmin for turning on the photocoupler PC is designed to satisfy {(V2-2Vfd−Vfp) / R2} − (Vfp / R1)> Ifpmin.

  Furthermore, the PNP open collector output is connected to the input terminal IN from the relationship among the external power supply V1, the forward voltage Vfd of the diodes D1, D2, and D3, the forward voltage Vfp of the photocoupler PC, and the resistors R1, R2, and R3. When connected, the primary current Ifpmin for turning on the photocoupler PC is designed to satisfy {(V1−Vfd−Vfp) / (R2 + R3)} − (Vfp / R1)> Ifpmin.

  Specific examples will be given according to the above conditions. For example, when the external power supply V1 is 24 volts (V), the internal power supply V2 is set to 5 volts (V).

  The resistor R1 is set to 820 ohms (Ω), the resistor R2 is set to 560 ohms (Ω), and the resistor R3 is set to 4.7 kiloohms (kΩ).

(When input signal is OFF)
When an input signal is not supplied to the input terminal IN, in the input circuit 100, the forward voltage Vfp of the photocoupler PC is limited by the resistor R1, and no current flows through the photocoupler PC. Therefore, a current flows through the path of the internal power supply V2, the diode D3, the resistor R1, the resistor R2, and the resistor R3. The current value is (5V−0.6V) /560Ω+4.7 kΩ + 820Ω≈0.72 mA. This current value is the current that always flows in the standby state. Further, the voltage value at both ends (one end side and the other end side) of the resistor R1 is 0.72 mA × 820Ω = 0.59 volts (V), and the voltage at both ends of the photocoupler PC is also equal to this, so that the photocoupler The value of PC forward voltage Vfp is not satisfied. As a result, the secondary side circuit is not turned ON.

(In case of NPN open collector output or relay output connection)
As shown in FIG. 4, when an NPN open collector output or a relay output is connected to the input terminal IN, in the input circuit 100, the internal power supply V2, the diode D3, the photocoupler PC, the resistor R1, the resistor R2, and the diode A current flows through the GND path of D2 and the external voltage V1. Here, since the resistance value of the resistor R3 is set large, almost no current flows to the resistor R3. Then, when a current flows toward the GND of the external voltage V1, the voltage at both ends (one end side and the other end side) of the resistor R1 satisfies the forward voltage Vfp of the photocoupler PC, and the secondary side circuit is turned on.

(PNP open collector output connection)
As shown in FIG. 4, when the PNP open collector output is connected to the input terminal IN, in the input circuit 100, the external power supply V1, the diode D1, the photocoupler PC and the resistor R1, the resistor R2, the resistor R3, the internal voltage Current flows through the GND path. Here, a current flows through the resistor R3 set to a large resistance value, but the external voltage V1 is larger than the internal voltage V2, and therefore, compared with the case where no input signal is given to the input terminal IN. A large current flows. Thereby, the voltage at both ends (one end side and the other end side) of the resistor R1 satisfies the forward voltage Vfp of the photocoupler PC, and the secondary side circuit is turned on.

As described above, as shown in FIG. 4, the input circuit 100 can handle any of PNP open collector output, NPN open collector output, and relay output. Further, since the value of the resistor R3 is set to be larger than the value of the resistor R2, it is possible to suppress power consumption that flows in a standby state when no input signal is given to the input terminal IN. Further, even if any of the PNP open collector output, the NPN open collector output, and the relay output is connected, the current flowing through the photocoupler PC is unidirectional, so that either a bipolar or unipolar photocoupler can be used.
Note that all of the NPN open collector output, PNP open collector output, and relay output shown in FIG. 4 are machine tools, production line sensors, sequencers (PLC, etc.), car washers, elevators, escalators, and other control devices. A light emitting device having a secondary circuit, a signal indicator lamp, a lighting device, a sound notification device, an information display device (LED, dot matrix display) ), An arbitrary device such as an interface converter and a communication converter is connected.

(Other embodiments)
FIG. 5 is a schematic diagram showing another example of the input circuit of FIG. Hereinafter, differences between the input circuit 100 of FIG. 5 and the input circuit 100 of FIG. 4 will be described.

  As shown in FIG. 5, the input circuit 100 may be provided with a Zener diode ZD instead of the resistor R3 of the input circuit 100 of FIG.

Next, design conditions for each parameter of the input circuit 100 will be described.
The relationship between the external power supply V1 and the internal power supply V2 when the PNP open collector output is connected to the input terminal IN, and the primary current for turning on the photocoupler PC when the NPN open collector output is connected to the input terminal IN The relation of Ifpmin is the same as that of the input circuit 100 in FIG.

  On the other hand, considering the case where none of the PNP open collector output, the NPN open collector output, and the relay output are input to the input terminal IN, the primary current Ifpmin for turning off the photocoupler PC is the reverse current Ir of the zener diode ZD. It is a condition that it is larger than.

  Further, from the relationship among the external power supply V1, the forward voltage Vfd of the diodes D1, D2, and D3, the forward voltage Vfp of the photocoupler PC, the voltage Vz of the Zener diode VZ, and the resistors R1 and R2, the PNP open collector When the output is connected to the input terminal IN, the primary side current Ifpmin for turning on the photocoupler PC satisfies {(V1−Vfd−Vfp−Vz) / R2} − (Vfp / R1)> Ifpmin. Designed.

  As a result, the input circuit 100 illustrated in FIG. 5 can perform the same operation as the input circuit 100 illustrated in FIG.

  Next, FIG. 6 or FIG. 7 is a schematic diagram for explaining the indicator lamp 200 including the input circuits 101 to 105 according to the present invention.

  As shown in FIGS. 6 and 7, the indicator lamp 200 includes an input circuit 101 ˜, an input circuit 105, a blinking unit 201, a buzzer unit 202, display units 203, 204, 205 (first stage, second stage, third stage, Stage).

  The input circuits 101, 102, 103, 104, and 105 shown in FIGS. 6 and 7 have the same circuit configuration as the input circuit 100 shown in FIGS.

  As shown in FIG. 6, the blinking unit 201 of the indicator lamp 200 is provided so as to be connectable with the PNP open collector output of the blinking unit output via the input circuit 101. Similarly, the buzzer unit 202 is provided so as to be connectable to the PNP open collector output of the buzzer unit output via the input circuit 102.

  The display unit (third stage) 203 is provided so as to be connectable to the PNP open collector output of the display unit (third stage) output via the input circuit 103, and the display unit (second stage) 204 is connected to the input circuit 103. The PNP open collector output of the display unit (third stage) output can be connected via the 104, and the display unit (first stage) 205 is connected to the PNP of the display unit (third stage) output via the input circuit 105. Provided to be connectable to the open collector output.

  In this way, the indicator lamp 200 including the input circuits 101 to 105 can be directly connected to the PNP open collector output without changing any switches or control devices.

  On the other hand, as shown in FIG. 7, the blinking unit 201 of the indicator lamp 200 is provided so as to be connectable to the NPN open collector output of the blinking unit output via the input circuit 101. Similarly, the buzzer unit 202 is provided so as to be connectable to the NPN open collector output of the buzzer unit output via the input circuit 102.

  The display unit (third stage) 203 is provided so as to be connectable to the NPN open collector output of the display unit (third stage) output via the input circuit 103, and the display unit (second stage) 204 is connected to the input circuit. The display unit (first stage) 205 is connected to the display unit (third stage) output NPN open collector output via 104, and the display unit (first stage) 205 is connected via the input circuit 105 to the display unit (third stage) output NPN. It is provided so that it can be connected to an open collector output.

  As described above, the indicator lamp 200 can be directly connected to the NPN open collector output without changing any switches or control devices. Therefore, the indicator lamp 200 can be directly connected to either the PNP open collector output or the NPN open collector output.

  As described above, PNP open collector output is mainstream in various parts of Europe such as Europe, and NPN open collector output is mainstream in Japan. Therefore, the input circuits 100, 101,..., 105 according to the present invention can be applied in any region, so that it is not necessary to change the model for each use region, smooth inventory holding, and cost reduction. be able to.

  In addition, as shown in FIG. 8, the input circuits 101 to 105 may be integrally provided as an integrated circuit 110. In this case, the circuit unit configuration can be simplified and simplified.

  Next, FIGS. 9 and 10 are schematic diagrams for explaining an audio output system 500 including input circuits 101 to 104 according to the present invention.

  As shown in FIGS. 9 and 10, the audio output system 500 includes input circuits 101 to, an input circuit 105, and an audio output device 300. The audio output device 300 includes a recording device 310.

  Note that the input circuits 101, 102, 103, and 104 shown in FIGS. 9 and 10 have the same circuit configuration as the input circuit 100 shown in FIGS.

  As shown in FIGS. 9 and 10, in the audio output system 500, the input circuit 101 is connected to the PNP open collector output. For example, when the PNP open collector output sets a flag according to the work start time (when there is an input signal), the input circuit 101 is turned on (ON), and the predetermined recording recorded from the audio output device 300 to the recording device 310 The message “Conveyor starts automatic operation” is pronounced.

  Similarly, when the input circuit 102 is connected to the PNP open collector output and the PNP open collector output sets a flag according to the working end time (when there is an input signal), the input circuit 102 is turned on (ON). Then, a predetermined message recorded in the recording device 310 from the audio output device 300 is pronounced “conveyor will automatically stop”.

  Similarly, when the input circuit 103 is connected to the PNP open collector output and the PNP open collector output detects an abnormality in the conveyor line, a flag is set (when there is an input signal), the input circuit 103 is turned on. (ON), a predetermined message recorded in the recording device 310 from the audio output device 300 is pronounced “conveyor line error”, and a flag is set in response to detection of intrusion in the conveyor line by the PNP open collector output. If there is an input signal from a sensor or the like, the input circuit 104 is turned on (ON), and a predetermined message recorded on the recording device 310 from the audio output device 300 “Please do not enter any further” Pronounced.

<Other examples>
1 to 5, the internal power supply terminal V2in is provided. However, the internal power supply V2 may be included in the input circuit 100 and the internal power supply terminal V2in may be omitted.

  Further, in the description of FIG. 9 and FIG. 10, a message is generated according to each of the input circuits 101,..., 104, but the present invention is not limited to this. When is turned on, another predetermined message may be pronounced.

  In the input circuit 100 and the integrated circuit 110 according to the present embodiment, the input terminal IN corresponds to the input terminal, the input circuits 100, 101 to 105 correspond to the input circuit, and the integrated circuit 110 corresponds to the integrated circuit. The diode D1 corresponds to the fourth diode, the resistor R1 corresponds to the fourth resistor, the resistor R2 corresponds to the fifth resistor, the resistor R3 or the Zener diode ZD corresponds to the sixth resistor, and the diode D2 corresponds to the fifth resistor. The diode D3 corresponds to the sixth diode, the internal power supply terminal V2in corresponds to the internal power supply terminal, the light emitting element HD corresponds to the light emitting element, the light receiving element PD corresponds to the light receiving element, and the internal power supply V2 Corresponds to the internal power supply, the external power supply V1 corresponds to the external power supply, and control devices such as machine tools, production line sensors, sequencers, car wash machines, elevators, escalators, etc. , Corresponds to the control device, the light emitting device, sound reporting device, information display device, inter Feisu converter and the like are equivalent to the control target device.

  From the above, the input circuits 100, 101,..., 105 and the integrated circuit 110 can cope with any of the PNP open collector output, the NPN open collector output, or the relay output, and the input signal is applied to the input terminal IN. Is set so that no current flows through the light-emitting element, the secondary circuit can be turned off in the standby state of the input circuit 100, and power consumption during standby can be suppressed.

  In addition, the integrated circuit 110 in which the input circuit 100 corresponding to all of the PNP open collector output, the NPN open collector output, and the relay output is integrated as an element can be used as a space-saving and one component. When a plurality of circuits are integrated, a common internal power supply terminal V2in can be used. Thus, the present invention can be applied to all products having an input circuit.

The preferred embodiment of the present invention is as described above, but the present invention is not limited thereto. It will be understood that various other embodiments may be made without departing from the spirit and scope of the invention. Furthermore, in this embodiment, although the effect | action and effect by the structure of this invention are described, these effect | actions and effects are examples and do not limit this invention.

Claims (8)

An input circuit for giving a signal input from a control device via an input terminal to a control target device,
A photocoupler capable of AC input from the input terminal via a first resistor; a first circuit connected to a power supply unit via a first diode;
An input circuit comprising: the photocoupler from the input terminal via the first resistor; and a second circuit grounded via a Zener diode. A second resistor is inserted between the photocoupler and the first diode of the first circuit;
The input circuit according to claim 1, wherein a third resistor is inserted between the photocoupler and the zener diode of the second circuit.   The input circuit according to claim 1, wherein the first diode is a Zener diode. An input circuit for giving a signal input from a control device via an input terminal to a control target device,
The anode of the fourth diode is connected to the input terminal side, the one end side of the fourth resistor is connected to the cathode side of the fourth diode, the one end side of the fifth resistor is connected to the other end side of the fourth resistor, One end of the sixth resistor is connected to the other end of the resistor, and the other end of the sixth resistor is grounded.
The anode of the fifth diode is connected to the other end side of the fifth resistor, one end side of the sixth resistor, and the cathode of the fifth diode is connected to the input terminal side;
A cathode of a sixth diode is connected to one end of the fourth resistor, and an internal power supply terminal is provided on the anode of the sixth diode;
An input circuit, wherein a light emitting element is connected in parallel with the fourth resistor, and a light receiving element is connected to face the light emitting element.   The input circuit according to claim 4, wherein a resistance value of the fifth resistor is lower than a resistance value of the sixth resistor.   6. The input circuit according to claim 4, wherein the fourth resistor has a resistance value that prevents at least a current from flowing through the light emitting element when an input signal to the input terminal is not input.   The input circuit according to claim 1, further comprising an internal power supply applied to the internal power supply terminal, wherein the internal power supply has a lower voltage than an external power supply in the control device. 8. An integrated circuit, wherein one or a plurality of the input circuits according to claim 1 are integrated to form an element.

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