Sunday, November 22, 2009

AVR Based Diode Temperature Meter

Temperature MeterThis is Multi channel diode temperature meter project with Microcontroller AVR AT90S2333 as main controller. It can be use to replace thermister temperature meter.

Front end of the temperature sensor and amplifier circuit consists of constant current. Approximately a constant current of 63µA sensor (diode) in the sink, a diode voltage drop of 3-fold amplification and A / D converter (10bit, 3.3V/fs) type. Drift in this block is the main cause of measurement error, the components must be selected as the low temperature drift.

Where an adjustment is not analog, EEPROM calibration parameters are calculated from the temperature to make sure that you store in it. The calibration process is required for proper equipment such as computer terminals instead of the driver. Some cases, ISP via cable (N81, 38.4kbps) has been to enter the calibration mode is turned on and connected.

Schematic and source code

Tag: Temperature Meter, Microcontroller AVR project, electronic project (src)