Direct-current (DC) solid-state relay

Abstract

The invention discloses a direct-current (DC) solid-state relay, and belongs to the relay field. The relay is composed of an input circuit, an isolating circuit and an output circuit which are sequentially connected together, wherein, the input circuit and the output circuit are respectively composed of a resistor, a switching tube and a diode, and a photoelectric coupler is adopted in the isolating circuit. The DC solid-state relay has the advantages that a positive feedback circuit is introduced into the input circuit so that the break-over voltage value and the cut-off voltage value of the relay are separated from each other and a certain margin is reserved; the relay has hysteresis characteristic, thus avoiding a critical jitter phenomenon; relay output is not affected by load, and ports are relatively independent; and the relay can accurately work in the case of an operation critical value, thus improving the operating stability.

Description

technical field [0001] The invention relates to a solid-state relay, in particular to a DC solid-state relay with hysteresis characteristics, and belongs to the field of relays. Background technique [0002] In the existing relay technology, most of the DC relays are electromagnetic relays. This type of relays generally attracts the armature through the magnetic effect generated by the coil to achieve the function of conducting and disconnecting the circuit. Since this electromagnetic relay adopts the electromagnetic principle, it is easily disturbed by the outside world. In addition, long-term use of the contacts of this relay will inevitably cause wear, especially in circuits with large currents. The arc formed by long-term conduction and disconnection will oxidize the contacts of the relay and affect the conduction and shutdown capabilities, thereby affecting To the proper effect and function of the circuit. Relatively speaking, because it has no movable mechanical cont...

AI Technical Summary

Problems solved by technology

[0003] The existing solid state relays have approximately the same critical voltage for turn-on and turn-off, and the action is inaccurate near the critical voltage, which is likely to cause misoperation

At the same time, the output of the relay is often affected by the size of the load. For a circuit with a changing load, the output voltage of the DC solid state relay will drift, resulting in unstable operation of the relay and reduced reliability.

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