An industrial sensor used to measure temperature, the Rosemount 214C from Emerson, has a nominal resistance of 100 ohms at 0 𝑜C, with a temperature coefficient of resistance (alpha) equal to 3.85*10 -3 / oC. It is used to measure temperatures ranging from – 45 oC to 455 oC. An alarm is to be raised when the temperature rises above 400 oC – a red LED, with a cut-in voltage of 1.8 V is to light up to indicate this status. If the maximum current through the LED is to be 10 mA, while that through the RTD is limited to 100 A, design an appropriate circuit for this purpose, so that the output voltage will not be greater than 5 V. You are provided with + 15 V supplies and may assume that all components are ideal.
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