Reliable working circuit of disposable environment-friendly lithium battery for liquid crystal display electric energy meter

Abstract

The invention relates to a reliable working circuit of a disposable environment-friendly lithium battery for a liquid crystal display electric energy meter. The reliable working circuit is characterized by comprising a single-chip U1, wherein the single-chip U1 is connected with a short connection point K3 through a resistor R51; the resistor R51 is connected with a resistor R46; the other end of the resistor R46 is grounded; the short connection point K3 is sequentially connected with a resistor R64, a diode D10 and a resistor R65; the other end of the resistor R65 is connected with a pin 73 of the single-chip U1; the short connection point K3 is connected with a diode D5; a voltage division circuit formed by the resistors R51 and R46 is connected with a pin 50 of the single-chip U1 to detect a lithium battery voltage; and the resistors R64 and R65 and the diode D10 are connected with the pin 73 of the single-chip U1 to form a discharging circuit of the lithium battery. When the liquid crystal display electric energy meter works normally, a low level signal is output by the single-chip to the lithium battery in timing to discharge, the lithium battery is in a working state during discharging, and the lithium battery does not discharge when the single-chip outputs a high level. The reliable working circuit of the disposable environment-friendly lithium battery for the liquid crystal display electric energy meter can provide a stable back-up power supply for the energy meter and ensure the correctness of a liquid crystal display electric energy meter clock and the power failure display function.

Description

technical field [0001] The invention relates to the technical field of metering, and relates to a reliable working circuit of a disposable environment-friendly lithium battery for a liquid crystal display electric energy meter. Background technique [0002] Disposable environmentally friendly lithium batteries, hereinafter referred to as lithium batteries, the positive electrode active material thionyl chloride of the lithium battery is in direct contact with the negative electrode active material metal lithium, and a dense lithium chloride passivation film will be formed on the surface of the metal lithium. On the one hand, this layer of passivation film can effectively protect the lithium surface from further corrosion, so that the lithium battery can be stored for a long time and has an excellent storage life. But on the other hand, because this layer of passivation film is an ion conductor and an electronic insulator, when the external circuit is connected, according to ...

AI Technical Summary

Problems solved by technology

The clock circuit in the liquid crystal display electric energy meter needs to be powered by a lithium battery to ensure the accuracy of the time after the mains power supply stops. stage requires a discharge current of a dozen milliamperes

In the previous liquid crystal display electric energy meter lithium battery circuit, only the lithium battery voltage detection circuit was used, and the influence due to the characteristics of the lithium battery itself was not considered.

If the liquid crystal display electric energy meter has been in operation for 1 year or longer in the field, the passivation film of the lithium battery will form. As a result, the lithium battery cannot provide a stable and reliable power supply voltage in a short period of time, resulting in insufficient power supply voltage for the clock circuit, affecting the stable operation of the clock circuit, and seriously causing the clock circuit to stop working for a short time. At this time, the time will return to an initial value

After the power supply is restored, the time in the liquid crystal display energy meter will start to run from a certain initial time. Since the time after the power supply is restored is not the real time recorded at that time, the data stored in the continuous operation is recorded at the wrong time. It will be executed according to the correct time, which means that the energy meter program will save the data according to the wrong time, then the execution time of each rate of the liquid crystal display electric energy meter will deviate from the normal setting value, and the data will not be recorded at the same time The data loses its authenticity

In addition to causing the displayed time and date to be incorrect, it will also cause non-settling on the settlement date, wrong rate execution, and many other problems such as electricity disputes for users

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