Avoiding saturation-to-zero of heaters in temperature regulators

A method is provided for avoiding heater saturation-to-zero in the design of automatic temperature regulators where both thermoelectric coolers (TEC) and heaters are used. The analysis is developed around a lumped parameter thermal model and the results are given for steady-state conditions. The particular case in which TEC commands should be found to avoid heater saturation is considered. A practical example is included.