Koninklijke Philips Corporation N.V.

North American Philips Corporation

Harold Garth Hanson

Jeffrey Alma West

Alma Stephenson Anderson

Brian C Martin

David William Oehler

The invention provides a clock sensor that can be operated at very low current and power. This sensor can also detect an input clock signal with a very small amplitude to detect the presence of clock inputs. According to one embodiment of the invention, a clock sensor comprises an input circuit configured to receive an input clock signal; a biasing circuit configured to receive the input clock signal and to provide biasing voltages; and a switching circuit configured to receive the biasing voltage and in response to the input clock signal, to provide a switching signal for switching an output circuit to generate an output clock signal. The input clock signal may have a small amplitude and the output clock signal has a full amplitude.

Low current clock sensor

Output overvoltage protection circuitry for circuits operating at low voltages (e.g., 3 v) interfacing to a higher voltage operating circuit (e.g., 5 v bus). To prevent problems with a pull-up PMOS device at the output when the bus is pulled-up to the higher voltage, a voltage node is provided in the circuit which follows the output voltage or the low supply voltage, whichever is higher, and a sub-circuit is provided to generate logic signals indicating when the bus is pulled too high. The PMOS device is then shut-down to prevent damage to the circuit.

Growing community of inventors

Albuquerque, NM, United States of America

Harold Garth Hanson