Clewett

David Clewett, Wotton Bassett GB

Patent application number	Description	Published
20090315410	Ultra-low current push-button switch interface circuit - Circuits and methods to achieve a switch interface circuit for a single pole, single throw (SPST) momentary push-button switch consuming a few tens of nanoamps whilst the push-button switch is closed, having low impedance input path when the switch is open in order to eliminate RFI interference have been achieved. The two states of the push-button switch, open and closed, maintain a low impedance path to one of the power supplies. The supply current is minimized whilst the switch is closed. The edge triggered detection of the switch event allows an extended switch-closed operation.	12-24-2009

Patent application number	Description	Published
20090261888	AUTONOMOUS CONTROL OF MULTIPLE SUPPLY VOLTAGE GENERATORS FOR DISPLAY DRIVERS - Circuits and methods to operate an arrangement of one or more charge pumps with two or more power supplies where each supply is able to vary over a range of voltages, and where any one supply can be of a higher or lower voltage than any of the others have been achieved. In a preferred embodiment the output of the arrangement of charge pumps is used to drive an electronic display. The strongest power supply available is selected and the arrangement of one or more charge pumps is reconfigured according to the value of the actual strongest supply voltage. In case of a change of a source of supply voltage the operation of the charge pumps during the short time required for reconfiguration. While the charge pump is running it can be suspended, reconfigured and released or restarted in the case of a change of supply source, or simply reconfigured on-the-fly without suspending in the case of a selected supply voltage change.	10-22-2009

Patent application number	Description	Published
20080197252	Dual release locking system for a sign supporting stand - A dual release locking system for locking and unlocking the foldable leg members of a sign supporting stand. For deployment, a locking pin can be retracted by the stepping action of a worker's foot or pulled by hand. Consequently, this same pin can be retracted for retrieval by a kicking action of a worker's foot or pulled by hand.	08-21-2008