Abstract: A control logic of a switched DC-to-DC converter allows continuous switching to bring the DC-to-DC converter to a final output value during a startup phase, it allows skipping of clock switching pulses if they are not needed and allows burst mode of switching pulses dependent on a load applied to the output voltage of the DC-to-DC converter. No digital or analog regulator is required for the control logic.

Abstract: Systems and methods to achieve a switched DC-to-DC converter having an improved efficiency have been disclosed. A control logic allows continuous switching to bring the DC-to-DC converter to a final output value during a startup phase, it allows skipping of clock switching pulses if they are not needed and allows burst mode of switching pulses dependent on a load applied to the output voltage of the DC-to-DC converter. No digital or analog regulator is required for the control logic.

Abstract: 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.

Abstract: 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.

Abstract: A compression and de-compression arrangement is provided for a display device having a display memory and a display. The arrangement includes a colour processor which reduces the colour samples by processing a pair of pixels to produce first and second luminance values and forming first and second output chrominance values from the pair of pixels. The first and second output chrominance values are formed by calculating for each pixel the corresponding U and V chrominance values and forming the first and second chrominance values (U, V) from the average of the values for each pixel. Forming the compressed representation of the colour image provides an advantage when recovering the original image, particularly for example where the image contains detail and/or text. The image processing apparatus of the system receives the group of colour component signal samples from the display memory and generates first and second output pixels, each comprising three colour component values (R, G, B), from each group.

Abstract: A dental mouthrinse is provided which is in the form of a clear solution saturated with respect to brushite and preferably also containing a source of fluoride ions such as to provide for example 3 to 20 ppm fluoride ions and a buffer with a molarity of for example 0.15 to 0.3M to provide a pH of 5.8 to 7.0. The mouth rinse is prepared by adding solid brushite to water to provide a solution containing excess solid brushite at a temperature of from 0.degree. to 15.degree. C, the solution is separated from excess brushite to provide a clear solution and the clear solution is allowed to come to an ambient temperature greater than 15.degree. C. Further ingredients of the mouth rinse may be added together with the solid brushite or to the clear solution after it has been allowed to come to ambient temperature. The mouth rinse is capable of recalcifying both dentine and tooth enamel and is particularly suitable for recalcifying early decayed areas in teeth.