3.5 Peltier Power Management

To control power, a switching FET is used to gate the flow of current through the Peltier element. Since a lot of current is passing through the circuit, it is critical that the transistor is fully saturated, and is not operating in the linear region. To ensure this occurs, a TC1413N MOSFET gate driver is used to switch the FET from the provided enable signal. The enable signal is set/cleared in software by the periodic self-check that manages the system. If a fault occurs, then the system disables the FET, which cuts off power to the Peltier. There’s an additional fuse inline with the Peltier circuit in the event of a more severe fault.