Overvoltage protection circuits
November 3, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3181033 3436601 Overvoltage protection means for protecting low power semiconductor components Voltage stabilizer suitable for a telephone set Overvoltage protection for a line circuit Voltage controlled transient protection unit Electrical circuit for protection against surge overvoltage of transients Overvoltage protection circuit Fault protection for integrated subscriber line interface circuits Protector circuit InventorAssigneeApplicationNo. 410439 filed on 09/21/1989US Classes:379/412, Protective circuit361/91.7, Protection by snubber circuitry361/119, In communication systems379/331, Having protective circuit379/413Power supply (e.g., battery feed)ExaminersPrimary: Dwyer, James L.Assistant: Shehata, Magdy W. Attorney, Agent or FirmInternational ClassesH02H 009/04H04M 007/00 Foreign Application Priority Data1988-11-11 GBAbstractAn overvoltage protection circuit for a pair of conductors carrying a balanced signal includes two similar protection elements connected in series between the conductors and two equal value resistors respectively connected in parallel with the elements, so that the junction point of the two elements is at a voltage midway between the voltages on the conductors and the protection elements present equal capacitances to the conductors. A third protection element is connected from the junction point of the two elements to ground to protect against excessive voltages relative to ground on the conductors. The voltage division provided by the resistors may be adjusted to improve the balance of the capacitances presented by the two protection elements. | |
