Patent ID: 11921531
Assignee: HAMILTON SUNDSTRAND CORPORATION
Field: Control (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A power supply system comprising:
a direct current (DC) power source;
a protection circuit having an input and an output, wherein the input is operably coupled to the DC power source so that, in operation, it receives DC power from the DC power source,
wherein the protection circuit includes:
a resistive first path formed of resistors and that has a first resistance; and
a transistor controlled second path that is in parallel with the resistive first path;
wherein both the resistive first path and the transistor controlled second path both electrically couple the input to the output, wherein the transistor controlled second path has a lower resistance than the first resistance;
wherein current passes, in operation, primarily through the resistive first path when a voltage at the input is greater than a threshold voltage related to a Zener diode in the second path and primarily through the second path when the voltage at the input is below the threshold voltage; and
a voltage regulator having an input coupled to the output of the protection circuit.