| 摘要 |
The present invention relates to the field of radio frequency identification, in particular to a temperature measurement and calibration circuit and a passive radio frequency identification tag. Meanwhile, the present invention further relates to a method for performing temperature measurement by using the tag. The temperature measurement and calibration circuit of the tag generates an upper reference voltage value limit and a lower reference voltage value limit, which do not change with temperature, then calibrates the upper reference voltage value limit and the lower reference voltage value limit to a uniform upper voltage value limit and a uniform lower voltage value limit, and eliminates the problem of different reference voltages of tags due to the power supply voltage fluctuation and process deviation. Meanwhile, a temperature measurement voltage generator circuit of the tag generates a calibration voltage value under a uniform calibration temperature. After the calibration voltage value is subjected to translational calibration, the calibration voltage values of the tags to be measured are equal, so that the consistency of temperature values of different tags is ensured. The circuit and tag provided by the present invention may be widely applied to ambient temperature detection, animal temperature detection, cold chain temperature detection or other fields, and have high accuracy of measurement. |
| 主权项 |
1. A temperature measurement and calibration circuit, comprising:
a reference voltage generator circuit, the input/output end of which is connected to an external detection device and the output ends of which are connected to a first amplifier circuit and a second amplifier circuit, respectively, configured to generate a first bandgap reference voltage signal, i.e., an upper reference voltage value limit, to the first amplifier circuit and a second bandgap reference voltage signal, i.e., a lower reference voltage value limit, to the second amplifier circuit, wherein the first bandgap reference voltage signal and the second bandgap reference voltage signal do not change with temperature or process parameters; a temperature measurement voltage generator circuit, the output end of which is connected to the external detection device and a voltage translation regulator circuit, configured to generate a voltage value which linearly changes with temperature; the voltage translation regulator circuit, the input end of which is connected to the external detection device and the temperature measurement voltage generator circuit, configured to translate and then output the temperature measurement value upon receiving a voltage translation regulation indication signal input from the external detection device; three amplifier circuits, wherein both the first amplifier circuit and the second amplifier circuit are connected like a unity-grain buffer and configured to separately adjust and then output the upper reference voltage value limit and the lower reference voltage value limit to an analog-to-digital converter circuit, and the third amplifier circuit is connected in such a way that the grain amplification factor is adjustable and configured to amplify the temperature measurement voltage value output by the voltage translation regulator circuit, adjust this temperature measurement voltage value to be between the upper reference voltage value limit and the lower reference voltage value limit, and output this temperature measurement voltage value to the analog-to-digital converter circuit; and the analog-to-digital converter circuit, configured to convert the upper reference voltage value limit and the lower reference voltage value limit into digital signals and convert the temperature measurement voltage value, which is output by the third amplifier circuit and between the upper reference voltage value limit and the lower reference voltage value limit, into a digital signal, wherein the digital signal is indicative of the temperature. |
