We offer the Grove Temperature Sensor, which uses a thermistor to return the ambient temperature in the form of a resistance value, which is then used to alter Vcc (5V with our Seeeduinos). Our board then converts this voltage value measured by an analog input pin to a temperature. The operating range is -40 to 125°C, with an accuracy of 1.5°C. For this price, it's hard to beat!
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