Methods and apparatus to detect leakage current in a resistance temperature detector

An apparatus comprising:

• a resistance temperature detector circuit to measure a temperature of an environment;
• a first resistance circuit;
• a second resistance circuit;
• and
• a comparator to determine a difference value corresponding to a comparison of a first voltage drop across the first resistance circuit under an applied current with a second voltage drop across the second resistance circuit under the applied current and to determine whether a current leak exists in the resistance temperature detector circuit based on the difference value.

A tangible machine readable storage medium comprising machine readable instructions, which when executed, cause a machine to at least:

• measure a first voltage at a first resistance circuit coupled to a resistance temperature detector circuit, measuring the first voltage being in response to applying a first current to the first resistance circuit;
• measure a second voltage at a second resistance circuit coupled to the resistance temperature detector circuit, measuring the second voltage being in response to applying a second current to the second resistance circuit;
• compare the first and second voltages to determine a difference value;
• and
• determine whether a current leak exists in the resistance temperature detector circuit based on whether the difference value is within a first range.