i am having a problem in calculating the output value from the lm335 precision temperature sensor where its output value is the input of ADC0804. With increase in temperature the value decreases instead of increasing.What might be the problem?
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2Please add a schematic of how you have the LM335 connected. – Anindo Ghosh Nov 27 '12 at 21:10
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Without a schematic, it is difficult to surmise what might be the problem.
At a guess, the device is not connected as shown in Figure 4 or 5 of the datasheet, fed from the circuit's Vcc through a an appropriate resistor (R1 in those figures), as described in the datasheet.
R1 is calculated such that current through the device is 1 mA (or up to 5 mA) with a voltage drop across the device for your ambient temperature, much like the calculation of current limiting resistors for LEDs.
The voltage drop calculation is provided on Page 8 of the datasheet.
Anindo Ghosh
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