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

Claim 9:
10. A method of extending an operational range of a power supply comprising:
providing a direct current (DC) power source;
providing 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 resistive elements and a transistor controlled second path, wherein 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 a resistance of the first path;
passing current 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
passing current primarily through the transistor controlled second path when the voltage at the input is below the threshold voltage.