CN211785950U

CN211785950U - Switch type signal detection circuit for preventing electrostatic interference

Info

Publication number: CN211785950U
Application number: CN201921937118.1U
Authority: CN
Inventors: 伍喆
Original assignee: Zhejiang Viewshine Intelligent Meter Co Ltd
Current assignee: Zhejiang Viewshine Intelligent Meter Co Ltd
Priority date: 2019-11-12
Filing date: 2019-11-12
Publication date: 2020-10-27
Anticipated expiration: 2029-11-12

Abstract

The utility model discloses a prevent electrostatic interference's on-off signal detection circuit. The utility model discloses a singlechip chip MCU, pull-up resistance R25, resistance R34, binding post P6, triode D10, filter capacitor C24. A 2 nd pin of the wiring terminal P6 and one end of the filter capacitor C24; the 1 st pin of the wiring terminal P6 is connected with the other end of the filter capacitor C24, one end of the pull-up resistor R25 and the M _ DETECT1 pin of the MCU; the other end of the pull-up resistor R25 is connected with one end of a resistor R34 and an M _ POW pin of the single chip microcomputer MCU; the other end of the resistor R34 is connected with the base of the triode D10, the collector of the triode D10 is connected with the 2 nd pin of the connecting terminal P6, and the emitter of the triode D10 is grounded. The utility model discloses thereby reduce instrument's trouble and damage, reduced the field maintenance cost.

Description

Switch type signal detection circuit for preventing electrostatic interference

Technical Field

The utility model belongs to the technical field of instrument and meter intelligent control, a triode, an electric capacity and two resistances are related to, through when detecting external switch signal, the switching on of control triode reaches the purpose that prevents electrostatic interference with cutting off the return circuit.

Background

Along with the development of the internet of things technology, instruments are also gradually intelligentized and connected into the internet of things, so that the intelligentization of the instrument industry is higher and higher, the production efficiency of enterprises is improved by applying the intelligent internet of things instruments, the convenience is brought to the lives of people, and the development of the society is greatly facilitated.

Meter electronics generally require a service life of 10 years or more, and therefore require products with good reliability. The gas meter MCU is used as a core component of the instrument and meter, and needs to ensure reliability and stability when used under working conditions. The switch signal detection circuit generally needs an external interface lead, and the tip of the lead is easy to cause electrostatic discharge, so that the MCU is reset and even damaged.

Disclosure of Invention

The utility model aims at providing a prevent electrostatic interference's switch mode signal detection circuit.

The utility model provides a technical scheme that its technical problem adopted as follows:

the utility model discloses a singlechip chip MCU, pull-up resistance R25, resistance R34, binding post P6, triode D10, filter capacitor C24.

A 2 nd pin of the wiring terminal P6 and one end of the filter capacitor C24; the 1 st pin of the wiring terminal P6 is connected with the other end of the filter capacitor C24, one end of the pull-up resistor R25 and the M _ DETECT1 pin of the MCU; the other end of the pull-up resistor R25 is connected with one end of a resistor R34 and an M _ POW pin of the single chip microcomputer MCU; the other end of the resistor R34 is connected with the base of the triode D10, the collector of the triode D10 is connected with the 2 nd pin of the connecting terminal P6, and the emitter of the triode D10 is grounded.

The model of the single chip microcomputer MCU is R7F0C019L2 DFB.

The type of the wiring terminal P6 is PH 2.0-2P.

The utility model discloses the circuit at first has the switch signal and DETECTs the function, and when needs detected switch signal, singlechip chip MCU's M _ POW pin provides the power for the circuit, opens the circuit simultaneously to ground return circuit, and singlechip chip MCU's M _ DETECT1 DETECTs the pin and then is invalid signal if detecting the high level, DETECTs the low level and then is valid signal, and detection time is less than 1 second usually. And after the detection is finished, the M _ POW pin of the MCU of the singlechip chip is powered off, and meanwhile, a circuit to ground loop is powered off. After the ground loop is cut off, the electrostatic energy release loop is cut off, so that the interference of static electricity on the MCU and the system of the singlechip chip is prevented.

The utility model discloses beneficial effect as follows:

the utility model discloses the circuit primary function is for detecting external switch signal, for example the valve detects signal etc. that targets in place. A detection port of the common switching signal detection circuit forms a loop with a system through an MCU pin all the time, and when static electricity is released, the energy can cause the reset or damage of the single chip microcomputer through the release of the system loop. The circuit realizes that a loop is formed only at the moment of detecting a signal by the detection circuit through circuit design, the loops are in a high-resistance and turn-off state in other time, and the loop for releasing the static electricity is cut off, so that the probability that the MCU is interfered by the static electricity is greatly reduced, the faults and damages of instruments and meters are reduced, and the field maintenance cost is reduced.

Drawings

FIG. 1 is a circuit diagram of the present invention;

the specific implementation mode is as follows:

in order to explain technical contents, structural features, and achieved effects of the present invention in detail, the following detailed description is made with reference to the accompanying drawings in combination with the embodiments.

As shown in fig. 1, the utility model discloses a singlechip chip MCU, pull-up resistance R25, resistance R34, binding post P6, triode D10, filter capacitor C24.

The utility model discloses the working process is as follows:

when a switching signal needs to be detected, the singlechip pin M _ POW outputs a high level to supply power to the 2 nd pin of a connecting terminal P6 in the detection circuit, meanwhile, the base electrode of the triode D10 is the high level, and if the switch connected with the connecting terminal P6 is conducted at the moment, the emitting junction of the triode D10 is forward biased, the polar junction is reverse biased, and the triode is conducted; the single chip pin M _ DETECT1 DETECTs the low level of the effective signal; if the switch connected to the connection terminal P6 is not turned on at this time, the single chip pin M _ DETECT1 DETECTs that the inactive signal generated through the pull-up resistor R25 is at a high level. The time of the whole detection process is less than 1 second, when the circuit does not need to detect signals, the triode D10 is always in an off state, a loop required by electrostatic discharge is not formed, and the system and the single chip microcomputer are protected from electrostatic interference.

Claims

1. A switch type signal detection circuit for preventing electrostatic interference is characterized by comprising a single chip Microcomputer (MCU), a pull-up resistor R25, a resistor R34, a wiring terminal P6, a triode D10 and a filter capacitor C24;