The hottest patent - a single-phase electronic key

Patent - a single-phase electronic keyboard prepaid watt hour meter

unlimited creativity, great instrument invention. Today, I will introduce a national invention authorized patent - a single-phase electronic keyboard prepaid watt hour meter. The patent was applied for by Zhejiang Chint Instrument Co., Ltd. and was authorized and announced on July 11, 2017

background of invention

it is very difficult to coordinate the two. At present, prepaid watt hour meters used in the market use various technologies to achieve the purpose of recharge and payment, such as contact IC card recharge, non-contact RF card recharge, and remote communication recharge. The above recharge methods have their own shortcomings: contact IC card recharge requires inserting the IC card into the card slot to realize the charging business, However, the slot of the contact IC card is easy to be maliciously damaged, resulting in failure to recharge; To recharge a contactless RF card, you only need to put the RF card within the RF range to realize the recharge business. Although the contactless RF card does not need to insert the RF card into the card slot, the contactless RF card is vulnerable to the surrounding electromagnetic interference, which leads to card reading errors and affects its use; Remote communication recharge realizes the recharge business through remote communication. Although this method avoids the shortcomings that the card slot is easy to be maliciously damaged and subjected to surrounding electromagnetic interference, data transmission may make mistakes in communication, and the stability and reliability of this method need to be improved

a new prepayment method is widely used by power users in the Middle East. The management system combines the user information and power purchase information to generate a set of encryption codes. The users themselves transmit the obtained encryption codes to the meter through the digital keyboard on the meter. After the meter is decrypted correctly, the stored power or amount is obtained and saved. This payment method is usually called keyboard prepaid watt hour meter because it uses the keyboard provided by the watt hour meter to recharge. Keyboard prepaid electric energy meter prepaid electric energy meter is provided to users in code form, which on the one hand avoids the problem that data transmission may make mistakes in remote communication recharge, on the other hand, it does not need to use card recharge, and there is no need for external interface on its electric energy meter, which has good sealing and prevents man-made damage. However, how the keyboard prepaid watt hour meter detects the power failure of the keyboard prepaid watt hour meter has not been disclosed at present

in order to solve the above technical problems, the invention is realized through the following technical scheme: a single-phase electronic keyboard prepaid watt hour meter, including SOC interface circuit, power supply circuit and power failure detection circuit, wherein, the power supply circuit includes an output terminal that provides DC power to the outside; The SOC interface circuit includes a control end. When the control end receives the on signal, the SOC interface circuit operates normally; When the control end receives the interrupt signal, the SOC interface circuit performs a power down data saving action; The power down detection circuit includes an input end and an output end. The input end of the power down detection circuit is connected with the output end of the power supply circuit for receiving the DC power provided by the power supply circuit; The output end of the power down detection circuit is connected with the control end of the SOC interface circuit; The power down detection circuit is used to detect the DC power provided by the power supply circuit in real time, and send the detection result to the control end of the SOC interface circuit; When the power down detection circuit detects that the DC current is greater than or equal to the preset voltage threshold, the power down detection circuit outputs an on signal to the SOC interface circuit; When the power down detection circuit detects that the DC is less than the preset voltage threshold, the power down detection circuit outputs an interrupt signal to the SOC interface circuit

the figure is the structural diagram of the single-phase electronic keyboard prepaid watt hour meter of the invention

the single-phase electronic keyboard prepaid watt hour meter, and the SOC interface circuit includes the system level chip att7035au and its peripheral circuits. The single-phase electronic keyboard prepaid watt hour meter, the power circuit includes ac/dc power conversion circuit and system working power circuit, the ac/dc power conversion circuit is used to provide DC power, and the system working power circuit is used to provide the working power of the system; The ac/dc power conversion circuit includes varistor rv1, transformer Tc1, diodes D23, D24, D25 and D26, and the diodes D23, D24, D25 and D26 form a full bridge rectifier; The working power supply circuit of the system includes capacitors C2, C4, C7, C8, C9, polar capacitors C1, C3, power regulator chip 7805, voltage regulator xc624p332pr; Alternating current is connected to the primary coil of the transformer Tc1 through the varistor rv1, the secondary coil of the transformer Tc1 is connected to the input end of the full bridge rectifier, and the output end of the full bridge rectifier is used as the output end of the ac/dc power conversion circuit to provide input signals to the power down detection circuit; The output end of the full bridge rectifier, the positive pole of the polar capacitor C1 and one end of the capacitor C2 are connected together to the in pin of the power regulator chip 7805, and the negative pole of the polar capacitor C1 is connected to the nano friction and wear tester at the other end of the capacitor C2 and then grounded together; One end of the positive pole of the polarity capacitor C3 and the capacitors C4 and C9 is connected and connected to the out pin of the power regulator chip 7805 and the VIN pin of the voltage regulator xc624p332pr at the same time. The negative pole of the polarity capacitor C3 is connected to the other end of the capacitors C4 and C9 and grounded together; The GND pin of the voltage regulator xc624p332pr and the power regulator chip 7805 is grounded, one end of the capacitors C7 and C8 is grounded after being connected in parallel, and the other end is connected to the Vout pin of the voltage regulator xc624p332pr

the single-phase electronic keyboard prepaid watt hour meter also includes a relay control circuit, which includes an l-phase relay control circuit and an n-phase relay control circuit; The l-phase relay control circuit and the n-phase relay control circuit have the same structure, wherein the l-phase relay control circuit and the n-phase relay control circuit both include triodes V4, V5, V8, V9, V12, V13, resistors R7, R8, R11, R12, R15, R16, R19, R20, R23, R24, R27, R28, diodes D6, D7, D10, D11 and magnetic holding relay

the single-phase electronic keyboard prepaid watt hour meter also includes a storage circuit for the ability of data storage materials to resist various deformation and damage. The data storage circuit includes a storage chip br24g128fj-we2, a capacitor C15, resistors R34, R35, one end of the capacitor C15, the 8 pin of the storage chip br24g128fj-we2, one end of the resistor R34 and one end of the resistor R35 are connected together to the 92 pin of the att7035au, The 6 pin of the memory core br24g128fj-we2 is connected with the other end of the resistor R34 and then connected with the 1 pin of the att7035au together. The 5 pin of the memory chip br24g128fj-we2 is connected with the other end of the resistor R35 and then connected with the 2 pin of the att7035au together. The other end of the capacitor C15 is connected with the 1 pin, 2 pin, 3 pin, 4 pin and 7 pin of the memory chip br24g128fj-we2 and then grounded together

compared with the prior art, the above technical scheme of the invention has the following advantages: (1) the single-phase electronic keyboard prepaid watt hour meter described in the invention includes SOC interface circuit, power supply circuit and power down detection circuit. The power down detection circuit detects the DC output of the power supply circuit. When the power down detection circuit detects that the DC output of the power supply circuit is greater than or equal to the preset voltage threshold, The power down detection circuit outputs the on signal to the SOC interface circuit, and the SOC interface circuit operates normally. When the power down detection circuit detects that the DC output from the power supply circuit is less than the preset voltage threshold, the power down detection circuit outputs the off signal to the SOC interface circuit, although the employees are in the weekend break time, the SOC interface circuit performs the power down data saving action. The power down detection circuit of the single-phase electronic keyboard prepaid watt hour meter provided by the invention can accurately detect the output DC power of the power supply circuit and ensure the reliability of the operation of the single-phase electronic keyboard prepaid watt hour meter. (2) The single-phase electronic keyboard prepaid watt hour meter described in the invention includes a system level chip att7035au, which, as an SOC system level chip, integrates a metering module, a clock circuit module, an LCD drive module and CPU resources, with a high degree of integration. (3) The single-phase electronic keyboard prepaid watt hour meter of the invention includes a relay control circuit, which controls the voltage polarity and current direction of the driving coil of the magnetic holding relay. (4) The single-phase electronic keyboard prepaid watt hour meter described in the invention includes a communication circuit, a keyboard circuit, a meter cover and an end button cover opening detection circuit, an AC sampling circuit, a strong magnetic detection circuit, a backlight screen control circuit, a buzzer alarm circuit, an active pulse output circuit, a second power pulse output circuit, and a data storage circuit. Compared with the prior art, it has higher integration, low cost, and simple and reliable design, Capable of mass production