Circuit and method for improving maximum working field strength of UHF RFID tag chip

Abstract

The invention discloses a circuit and a method for improving the maximum working field strength of an ultra-high frequency RFID tag chip. The circuit includes: an antenna for transmitting and receiving wireless AC signals; Under the control of the control signal output by the hysteresis comparator array, a certain capacitor branch is selectively connected to change the impedance of the circuit; an AC-DC converter is used to convert the wireless signal received by the antenna into a DC voltage VDD for the label chip to work The voltage detection network detects the DC voltage VDD by detecting the magnitude of the current flowing through the leakage circuit to obtain n+1 output voltages; the hysteresis comparator array is used to compare the n+1 voltage outputs of the voltage detection network to By outputting n control signals to the capacitor array, the invention can realize the improvement of the maximum working field intensity of the RFID tag chip.

Description

technical field [0001] The invention relates to a radio frequency identification (Radio Frequency Identification, RFID) technology, in particular to a circuit and a method for increasing the maximum working field strength of a UHF RFID tag chip. Background technique [0002] For a UHF RFID tag, when the tag chip is very close to the reader, the voltage of the circuit obtained through the rectifier will be far greater than the voltage that the device can withstand, which will cause the device to break down and fail. The most commonly used solution now is to design a bleeder circuit in the tag chip so that the output voltage of the rectifier can be effectively controlled within the voltage that the integrated device can withstand. However, the disadvantage of this method for ordinary UHF RFID chip tags is that it will cause chip heating and disturbance of the internal signal of the chip, which will affect the life of the device, the stability of the circuit and the reliability...

AI Technical Summary

Problems solved by technology

However, the disadvantage of this method for ordinary UHF RFID chip tags is that it will cause chip heating and disturbance of the internal signal of the chip, which will affect the life of the device, the stability of the circuit and the reliability of the memory data. For a temperature sensor As far as UHF RFID tags are concerned, in addition to the above problems, the measured temperature will also be inaccurate, so it is necessary to propose a technical means to solve the above problems

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