Title :
Circuit design and implementation for digital temperature and humidity measurement and control
Author :
Hui, Cao ; Junnai, Huang
Author_Institution :
Microelectron. Dept., Fudan Univ., Shanghai, China
Abstract :
This paper describes a mixed signal, low power circuit design for temperature and humidity measurement and control. Temperature and humidity are sensed using a thermistor sensor and a hygrometer sensor. The theory of an RC oscillator is used to convert sensor resistance into a frequency signal. A ROM (Read Only Memory) is used to map the Schmitt trigger frequency onto temperature and humidity. The control block can control the outer device to implement some demand according to the value of measurement. This circuit can measure temperature to an accuracy of 1 V in the range of -20°C to 60°C and measure humidity to an accuracy of 10%RH in the range of 40%RH to 90%RH
Keywords :
convertors; digital control; digital instrumentation; humidity control; humidity measurement; integrated circuit design; low-power electronics; mixed analogue-digital integrated circuits; read-only storage; temperature control; temperature measurement; -20 to 60 degC; ASIC design; RC oscillator; ROM; Schmitt trigger frequency; digital humidity measurement; digital temperature measurement; humidity control; hygrometer sensor; low power circuit design; mixed signal circuit design; read only memory; resistance/frequency conversion; temperature control; thermistor sensor; Circuit synthesis; Electrical resistance measurement; Humidity control; Humidity measurement; Read only memory; Temperature control; Temperature measurement; Temperature sensors; Thermal sensors; Thermistors;
Conference_Titel :
ASIC, 2001. Proceedings. 4th International Conference on
Conference_Location :
Shanghai
Print_ISBN :
0-7803-6677-8
DOI :
10.1109/ICASIC.2001.982610
