CN217721157U - Signal conversion circuit - Google Patents
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- CN217721157U CN217721157U CN202221791118.7U CN202221791118U CN217721157U CN 217721157 U CN217721157 U CN 217721157U CN 202221791118 U CN202221791118 U CN 202221791118U CN 217721157 U CN217721157 U CN 217721157U
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Abstract
The embodiment of the utility model discloses signal conversion circuit, including the relay, the electrical power unit, steady voltage unit and status indication unit, the first input end of relay and the first input node coupling of circuit, two outputs of relay respectively with two output node couplings of circuit, the second input end coupling of electrical power unit and relay, the one end of steady voltage unit and the second input end coupling of relay, the other end ground connection of steady voltage unit and with the second input node coupling of circuit, status indication unit connects in parallel at first input and second input both ends, control power unit, the relay, the voltage parameter of steady voltage unit. The utility model discloses a signal conversion circuit can compatible passive node input and the active node input of not distinguishing polarity to unify the passive node output for the relay, reduced connect the wrong line, connect the inconvenience that the reverse line brought.
Description
Technical Field
The utility model relates to a signal processing field particularly, relates to a signal conversion circuit.
Background
Sensors are usually required to be connected into a low-voltage switch cabinet, and two normal signals are provided, wherein one is a dry node, namely a passive node, namely the on-off of the node; the other is a wet node, i.e., an active node (DC 24V). The equipment in the switch cabinet processes the signals, so that whether a preset scene occurs or not is judged, and relevant coping operations are adopted.
In the prior art, for a signal receiving device that needs to access a signal, it is necessary to know whether the signal is an active node or a passive node in advance, and determine the signal by using a corresponding detection method according to the type of the node. The traditional detection mode is as follows: when the passive node is accessed, the on-off of the optical coupler is used for isolation and detection, and when the active node is accessed, the mode of directly driving the relay or the mode of AD sampling of the active node is used for processing. In practical operation, the conventional detection mode may cause problems of wrong connection, reverse connection and the like when detection circuits of different nodes are arranged.
SUMMERY OF THE UTILITY MODEL
A primary object of the present invention is to provide a signal conversion circuit, which solves the above-mentioned problems existing in the prior art.
To achieve the above object, the present invention provides a signal conversion circuit, including:
a relay, a first input terminal of the relay being coupled to a first input node of the circuit, two output terminals of the relay being coupled to two output nodes of the circuit, respectively;
a power supply unit coupled with a second input of the relay;
one end of the voltage stabilizing unit is coupled with the second input end of the relay, and the other end of the voltage stabilizing unit is grounded and coupled with the second input node of the circuit;
the output voltage of the power supply unit is within the action voltage range of the relay, the output voltage is lower than the regulated voltage of the voltage regulation unit, and the difference between the high voltage in the active node signal received by the circuit and the regulated voltage is within the action voltage range.
In some embodiments, the power supply unit includes a power supply, a self-recovery fuse, and an anti-reverse diode coupled in sequence, and a cathode of the anti-reverse diode is coupled to the second input terminal.
In some embodiments, the voltage regulation unit is a bidirectional voltage regulation unit, the relays are electrodeless relays, and the differences between the high voltages in the active node signals received by the circuit and the bidirectional voltage regulation voltages of the bidirectional voltage regulation unit are within the action voltage range.
In some embodiments, the bidirectional regulator block comprises two zener diodes of the same regulation parameter connected in series in opposite directions.
In some embodiments, the circuit further comprises:
the state indicating unit is connected in parallel to two ends of the first input end and the second input end;
when the relay acts due to voltages of different polarities, the state indicating unit provides different state indications.
In some embodiments, the status indication unit comprises:
a current limiting unit, one end of which is coupled with the second input end;
the anode of the first unidirectional conduction light-emitting unit is coupled with the first input end, and the cathode of the first unidirectional conduction light-emitting unit is coupled with the other end of the current-limiting unit;
the anode of the second unidirectional conduction light-emitting unit is coupled with the other end of the current-limiting unit, and the cathode of the second unidirectional conduction light-emitting unit is coupled with the first input end;
the providing different status indications by the status indicating unit when the relay is operated by voltages of different polarities comprises:
when the relay is operated due to the positive polarity voltage between the first input end and the second input end, the first one-way conduction light-emitting unit emits light;
when the relay acts because of the negative voltage between the first input end and the second input end, the second one-way conduction light-emitting unit emits light.
In some embodiments, the first and second unidirectional conducting light emitting units are both light emitting diodes.
In some embodiments, the current limiting unit is composed of a first current limiting resistor, a second current limiting resistor and a third current limiting resistor;
one end of the first current-limiting resistor and one end of the third current-limiting resistor after being connected in parallel are coupled with the second input end, the other end of the first current-limiting resistor and one end of the second current-limiting resistor are connected in series, and the other end of the second current-limiting resistor is coupled with the cathode of the first one-way conduction light-emitting unit and the anode of the second one-way conduction light-emitting unit.
In some embodiments, the status indication unit further comprises:
and one end of the bidirectional TVS is coupled with the first input end, and the other end of the bidirectional TVS is coupled with one end of the second current-limiting resistor.
In some embodiments, the first input node of the circuit is coupled to the first input terminal through an i-inductor.
The embodiment of the utility model provides a signal conversion circuit adopts the relay as actuating mechanism to circuit structure such as cooperation voltage stabilizing unit can compatible active node input and passive node input, and unify to relay output. The signal receiving equipment does not need to consider the type of the signal any more and processes the signal uniformly according to the passive signal. Furthermore, the utility model discloses a signal conversion circuit's steady voltage unit is two-way steady voltage unit, need not to distinguish active node's input polarity, can be compatible not distinguish the active node input of polarity. The utility model discloses a signal conversion circuit significantly reduced connect wrong line, connect the inconvenience that the reverse line brought.
Drawings
Fig. 1 is a diagram illustrating an upstream-downstream connection relationship of a signal conversion circuit according to an embodiment of the present invention.
Fig. 2 is a circuit diagram of a signal conversion circuit according to an embodiment of the present invention.
The realization, the functional characteristics and the advantages of the utility model are further explained by combining the embodiment and referring to the attached drawings.
Detailed Description
The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is to be understood that the embodiments described are only some of the embodiments of the present invention, and not all of them. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts all belong to the protection scope of the present invention. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The utility model discloses a signal conversion circuit is applied to the low-voltage switchgear, specifically, as shown in fig. 1, the utility model discloses a signal conversion circuit can be applied to the processing of well fire control signal in the low-voltage switchgear, and signal conversion circuit is used for the active and passive fire control signal in compatible receipt upper reaches to the fire control signal receiving equipment of output for the low reaches. The utility model discloses do not restrict signal conversion circuit's application range, except the fire control signal, signal conversion circuit still can be applied to other active signal and passive signal's processing.
Referring to fig. 2, fig. 2 is a circuit diagram of a signal conversion circuit according to an embodiment of the present invention.
The signal conversion circuit has two input nodes and two output nodes, respectively: a first input node S _ IN +, a second input node S _ IN-, a first output node S _ OUT +, and a second output node S _ OUT-. The signal conversion circuit further comprises a relay K1, a power supply unit and a voltage stabilizing unit.
Relay K1 has four pins, and wherein, 4 feet and 1 foot are relay K1's first input and second input respectively, and 2 feet and 3 feet are relay K1's first output and second output respectively. The relay K1 is an electrodeless relay, the input of the pin 1 and the pin 4 do not distinguish polarity, and the relay K1 can act after the action voltage of the relay K1 is applied between the pin 1 and the pin 4, namely the pin 2 and the pin 3 of the relay K1 are conducted.
The first input node S _ IN + is coupled with the 4 pins of the relay K1, the power supply unit is coupled with the 1 pin of the relay K1, the first output node S _ OUT + is coupled with the 2 pins of the relay K1, and the second output node S _ OUT-is coupled with the 3 pins of the relay K1. One end of the voltage stabilizing unit is coupled with the pin 1 of the relay K1, and the other end of the voltage stabilizing unit is grounded and coupled with the second input node S _ IN-. IN this embodiment, the direction of the voltage stabilizing unit is not limited, and one end coupled to pin 1 of the relay K1 may be used as the input end of the voltage stabilizing unit, or one end coupled to the second input node S _ IN-may be used as the input end of the voltage stabilizing unit.
The output voltage of the power supply unit is within the action voltage range of the relay K1, the output voltage is lower than the regulated voltage of the voltage stabilizing unit, and the difference between the high voltage and the regulated voltage in the active node signal received by the signal conversion circuit is within the action voltage range of the relay K1.
The signal conversion circuit of the present embodiment can cause the relay K1 to operate and complete the output when facing both the dry node input and the wet node input, and the specific operation principle is as follows.
When the input node of the signal conversion circuit is a dry node (i.e., a passive node):
if the first input node S _ IN + and the second input node S _ IN-are open-circuited, the potentials of the pin 1 and the pin 4 of the relay K1 are both the potentials output by the power supply unit, so that no voltage drop exists between the pin 1 and the pin 4, the relay K1 does not act, the pin 2 and the pin 3 of the relay K1 are open-circuited, and the first output node S _ OUT + and the second output node S _ OUT-are open-circuited;
if the first input node S _ IN + and the second input node S _ IN-are short-circuited, the output voltage of the power supply unit is applied between pin 1 and pin 4 of the relay K1, at the moment, pin 4 is 0V, pin 1 is the potential output by the power supply unit, therefore, the voltage drop between pin 1 and pin 4 is that the output voltage of the power supply unit is IN the action voltage range of the relay K1, the relay K1 acts, the pin 2 and pin 3 of the relay K1 are short-circuited, and the first output node S _ OUT + and the second output node S _ OUT-are short-circuited.
When the input node of the signal conversion circuit is a wet node (i.e., an active node):
if the active node signal is input to 0V, namely the first input node S _ IN + is 0V and the second input node S _ IN-is 0V, the potentials of the pin 1 and the pin 4 of the relay K1 are the potentials output by the power supply unit, so that no voltage drop exists between the pin 1 and the pin 4, the relay K1 does not act, the pin 2 and the pin 3 of the relay K1 are open-circuited, and the first output node S _ OUT + and the second output node S _ OUT-are open-circuited;
if the active node signal is inputted with a high voltage, if the second input node S _ IN-is at a high level, the first input node S _ IN + is 0V, and the end coupled to the second input node S _ IN-is used as the input end of the voltage stabilizing unit. The voltage stabilizing unit is stabilized at a stabilized voltage, pin 1 of the relay K1 is the difference between the high voltage in the active node signal and the stabilized voltage, pin 4 is 0V, the voltage drop between pin 1 and pin 4 is within the action voltage range of the relay K1, the relay K1 acts, pin 2 and pin 3 of the relay K1 are in short circuit, and the first output node S _ OUT + and the second output node S _ OUT-are in short circuit.
If the active node signal is inputted with a high voltage, if the first input node S _ IN + is at a high level, the second input node S _ IN-is at 0V, and the end coupled to pin 1 of the relay K1 is used as the input end of the voltage stabilizing unit. The voltage stabilizing unit is stabilized at a stabilized voltage, pin 1 of the relay K1 is the difference between a high voltage in the active node signal and the stabilized voltage, pin 4 is a high potential, the voltage drop between pin 4 and pin 1 is within the action voltage range of the relay K1, the relay K1 acts, pin 2 and pin 3 of the relay K1 are in short circuit, and the first output node S _ OUT + and the second output node S _ OUT-are in short circuit.
In the embodiment, the signal conversion circuit can be compatible with active node input and passive node input and is unified into relay output. Subsequent signal receiving equipment does not need to consider the type of the signal any more and processes the signal uniformly according to the passive signal.
In some embodiments, the voltage regulation unit is a bidirectional voltage regulation unit, that is, both ends of the voltage regulation unit can be used as input ends, and the difference between the high voltage in the active node signal received by the signal conversion circuit and the bidirectional voltage regulation voltage of the bidirectional voltage regulation unit is within the operation voltage range of the relay K1. Specifically, the bidirectional voltage stabilizing unit comprises two voltage stabilizing diodes with the same specification, namely a first voltage stabilizing diode D2 and a second voltage stabilizing diode D3, which are connected in series in an inverted manner. The difference between the high voltage in the active node signal received by the signal conversion circuit and the regulated voltage of the first voltage-regulator diode D2 is within the operating voltage range of the relay K1, and the difference between the high voltage in the active node signal received by the signal conversion circuit and the regulated voltage of the second voltage-regulator diode D3 is within the operating voltage range of the relay K1. As a possible way, the cathode of the first zener diode D2 and the cathode of the second zener diode D3 are coupled.
In some embodiments, the power supply unit includes a power supply, a self-recovery fuse F1, and an anti-reverse diode D1 coupled in sequence. When the zener diode D3 is in a short-circuit failure mode, the self-recovery fuse F1 can prevent the 12V power supply from being damaged. The cathode of the reverse-connection preventing diode D1 is coupled with the pin 1 of the relay K1.
In some embodiments, the signal conversion circuit further comprises a status indication unit connected in parallel across pins 1 and 4 of the relay K1 for providing different status indications when the relay K1 is activated by voltages of different polarities.
The status indication unit in this embodiment includes: the LED lamp comprises a first unidirectional conduction light emitting unit D5, a second unidirectional conduction light emitting unit D10, a first current limiting resistor R1, a second current limiting resistor R2, a third current limiting resistor R3 and a bidirectional transient suppression diode (TVS) D4. Since the one-way conduction light-emitting unit has an anode and a cathode, when a rated voltage is applied between the anode and the cathode, the one-way conduction light-emitting unit emits light, and when the voltage is reversed, the one-way conduction light-emitting unit does not emit light, the embodiment uses the first one-way conduction light-emitting unit D5 and the second one-way conduction light-emitting unit D10 to indicate the operating state of the signal conversion circuit. Specifically, the first one-way conduction light emitting unit D5 and the second one-way conduction light emitting unit D10 may be a single circuit element, or may be formed by a plurality of circuit elements together, and in this embodiment, for simplicity of description, light emitting diodes are used as the one-way conduction light emitting units, that is, the first one-way conduction light emitting unit D5 is a first light emitting diode, and the second one-way conduction light emitting unit D10 is a second light emitting diode. One end of the first current limiting resistor R1 and the third current limiting resistor R3 which are connected in parallel is coupled with 1 pin of the relay K1, the other end of the first current limiting resistor R1 is coupled with one end of the second current limiting resistor R2 and one end of the bidirectional TVS D4, the other end of the second current limiting resistor R2 is coupled with the cathode of the first light emitting diode D5 and the anode of the second light emitting diode D10, and the other end of the bidirectional TVS D4, the anode of the first light emitting diode D5 and the cathode of the second light emitting diode D10 are coupled to 4 pins of the relay K1. The first current limiting resistor R1, the second current limiting resistor R2, and the third current limiting resistor R3 together form a current limiting unit to provide current limiting for the first light emitting diode D5 and the second light emitting diode D10, and the bidirectional TVS D4 can prevent the voltages at the two ends of the first light emitting diode D5 and the second light emitting diode D10 from being too high.
IN some embodiments, the first input node S _ IN + is coupled to the 4-pin of the relay K1 through the i-inductor L1, and when the input node is an active node, the i-inductor L1 may perform a current limiting function at the moment of power-on.
In some embodiments, the active signal input is DC24V, the i-inductor L1 is 10mH, the first zener diode D2 and the second zener diode D3 are 14V zener diodes, the relay K1 is a 12V relay, and ± 9V to 15.6V is applied between pin 1 and pin 4 of the relay K1 to enable the relay to operate (i.e., pin 2 and pin 3 are turned on), the power supply in the power module is a 12V power supply, the first current limiting resistor R1 and the third current limiting resistor R3 are both 2K Ω, the second current limiting resistor R2 is 1K Ω, and the bidirectional TVS D4 is a 5V bidirectional TVS.
The signal conversion circuit of the embodiment can cause the relay K1 to operate and complete output when facing both dry node input and forward and reverse wet node input, and the specific working principle is as follows.
When the input node of the signal conversion circuit is a dry node (i.e., a passive node):
if the first input node S _ IN + and the second input node S _ IN-are open-circuited, the pin 1 and the pin 4 of the relay K1 are both +12V, no voltage drop exists between the pin 1 and the pin 4 of the relay K1, the first light-emitting diode D5 and the second light-emitting diode D10 cannot be lightened, the relay K1 does not act, the pin 2 and the pin 3 of the relay K1 are open-circuited, and the first output node S _ OUT + and the second output node S _ OUT-are open-circuited;
if the first input node S _ IN + and the second input node S _ IN-are short-circuited, the +12V of the power supply unit is applied between the pin 1 and the pin 4 of the relay K1 through the self-recovery fuse F1 and the anti-reverse connection diode D1, at the moment, the pin 4 is 0V, the pin 1 is +12V, the first light-emitting diode D5 cannot be lightened, the second light-emitting diode D10 is lightened, the voltage drop 12V between the pin 1 and the pin 4 is positioned IN the action voltage range of the relay K1, the relay K1 acts, the pin 2 and the pin 3 of the relay K1 are short-circuited, and the first output node S _ OUT + and the second output node S _ OUT-are short-circuited.
When the input node of the signal conversion circuit is a wet node (i.e., an active node):
if the active node signal is input by 0V, namely the first input node S _ IN + is 0V and the second input node S _ IN-is 0V, the potentials of the pin 1 and the pin 4 of the relay K1 are both +12V of the power supply unit, no voltage drop exists between the pin 1 and the pin 4, the first light-emitting diode D5 and the second light-emitting diode D10 cannot be lightened, the relay K1 does not act, an open circuit exists between the pin 2 and the pin 3 of the relay K1, and an open circuit exists between the first output node S _ OUT + and the second output node S _ OUT-;
if the first input node S _ IN + inputs high voltage, namely the first input node S _ IN + is 24V and the second input node S _ IN-is 0V, the second voltage-stabilizing diode D3 is rapidly broken down and stabilized at 14V, at the moment, the voltage drop between the pin 4 and the pin 4 of the relay K1 is +24V, the pin 1 is +14V, the voltage drop between the pin 1 and the pin 4 is more than 9V, the first light-emitting diode D5 is lightened, the second light-emitting diode D10 is not lightened, the relay K1 is actuated, the pin 2 and the pin 3 of the relay K1 are short-circuited, and the first output node S _ OUT + and the second output node S _ OUT-are short-circuited;
if the second input node S _ IN-is inputted with a high voltage, i.e., the second input node S _ IN-is 24V and the first input node S _ IN + is 0V, the first zener diode D2 is rapidly broken down and stabilized at 14V, pin 4 of the relay K1 is 0V, pin 1 is +10V, the voltage drop between pin 1 and pin 4 is greater than 9V, the first led D5 is not lit, the second led D10 is lit, the relay K1 is operated, the pin 2 and pin 3 of the relay K1 are shorted, and the first output node S _ OUT + and the second output node S _ OUT-are shorted.
It can be seen that, no matter the first input node S _ IN + is 24V, the second input node S _ IN-is 0V, or the second input node S _ IN-is 24V, and the first input node S _ IN + is 0V, the signal conversion circuit of the present embodiment can achieve relay output, that is, the signal conversion circuit of the present embodiment does not need to distinguish the polarity of the active input.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrases "comprising a," "8230," "8230," or "comprising" does not exclude the presence of other like elements in a process, method, article, or system comprising the element.
The above embodiment numbers of the present invention are only for description, and do not represent the advantages and disadvantages of the embodiments.
The above is only the preferred embodiment of the present invention, and not the scope of the present invention, all the equivalent structures or equivalent flow changes made by the contents of the specification and the drawings or the direct or indirect application in other related technical fields are included in the patent protection scope of the present invention.
Claims (10)
1. A signal conversion circuit, comprising:
a relay, a first input terminal of the relay being coupled to a first input node of the circuit, two output terminals of the relay being coupled to two output nodes of the circuit, respectively;
a power supply unit coupled with a second input of the relay;
one end of the voltage stabilizing unit is coupled with the second input end of the relay, and the other end of the voltage stabilizing unit is grounded and coupled with a second input node of the circuit;
the output voltage of the power supply unit is within the action voltage range of the relay, the output voltage is lower than the regulated voltage of the voltage stabilizing unit, and the difference between the high voltage in the active node signal received by the circuit and the regulated voltage is within the action voltage range.
2. The circuit of claim 1, wherein the power supply unit comprises a power supply, a self-recovery fuse, and an anti-reverse diode coupled in sequence, a cathode of the anti-reverse diode being coupled to the second input terminal.
3. The circuit of claim 1, wherein the voltage regulation unit is a bi-directional voltage regulation unit, the relays are electrodeless relays, and the difference between the high voltage of the active node signal received by the circuit and the bi-directional regulated voltage of the bi-directional voltage regulation unit is within the operating voltage range.
4. The circuit of claim 3, wherein the bi-directional regulator block includes two zener diodes of the same regulation parameter connected in anti-series.
5. The circuit of claim 3, wherein the circuit further comprises:
the state indicating unit is connected in parallel to two ends of the first input end and the second input end;
when the relay acts due to voltages of different polarities, the state indicating unit provides different state indications.
6. The circuit of claim 5, wherein the status indication unit comprises:
a current limiting unit, one end of the current limiting unit being coupled with the second input terminal;
the anode of the first unidirectional conduction light-emitting unit is coupled with the first input end, and the cathode of the first unidirectional conduction light-emitting unit is coupled with the other end of the current-limiting unit;
the anode of the second one-way conduction light-emitting unit is coupled with the other end of the current limiting unit, and the cathode of the second one-way conduction light-emitting unit is coupled with the first input end;
when the relay acts due to voltages with different polarities, the state indicating unit provides different state indications, including:
when the relay acts because a positive polarity voltage exists between the first input end and the second input end, the first one-way conduction light-emitting unit emits light;
when the relay acts because of the negative voltage between the first input end and the second input end, the second one-way conduction light-emitting unit emits light.
7. The circuit of claim 6, wherein the first and second unidirectionally conducting light emitting units are both light emitting diodes.
8. The circuit of claim 6, wherein the current limiting unit is comprised of a first current limiting resistor, a second current limiting resistor, a third current limiting resistor;
one end of the first current limiting resistor and one end of the third current limiting resistor after being connected in parallel are coupled with the second input end, the other end of the first current limiting resistor and one end of the second current limiting resistor are connected in series, and the other end of the second current limiting resistor is coupled with the cathode of the first one-way conduction light-emitting unit and the anode of the second one-way conduction light-emitting unit.
9. The circuit of claim 8, wherein the status indication unit further comprises:
and one end of the bidirectional TVS is coupled with the first input end, and the other end of the bidirectional TVS is coupled with one end of the second current-limiting resistor.
10. The circuit of any of claims 1-9, wherein the first input node of the circuit is coupled to the first input terminal through an i-inductor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221791118.7U CN217721157U (en) | 2022-07-12 | 2022-07-12 | Signal conversion circuit |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202221791118.7U CN217721157U (en) | 2022-07-12 | 2022-07-12 | Signal conversion circuit |
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| CN217721157U true CN217721157U (en) | 2022-11-01 |
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| CN202221791118.7U Active CN217721157U (en) | 2022-07-12 | 2022-07-12 | Signal conversion circuit |
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