Abstract: A system includes an inductor having first and second terminals. First and second transistors have first terminals connected to the first and second terminals of the inductor, respectively, and second terminals connected to a power supply and a common potential, respectively. Third and fourth transistors have first terminals connected to the first and second terminals of the inductor, respectively, and second terminals providing first and second output voltages of first and second polarities, respectively. First and second feedback circuits generate first and second feedback signals based on the first and second output voltages, respectively. A first control circuit controls the first and third transistors based on the second feedback signal and not based on the first feedback signal. A second control circuit controls the second and fourth transistors based on the first feedback signal and not based on the second feedback signal.

Abstract: A step-up/step-down switching regulator control method for a regulator having an inductor with first and second leads, a first switch for controllably coupling the first lead to a source of power, a first device between the first lead and a circuit ground, a second switch for controllably coupling the second lead to the circuit ground, and a second device between the second lead and a regulator, the method comprising operating the switches in a sequence of phases when the source of power has a voltage exceeding the regulator output and in the same sequence of phases when the source of power has a voltage less than the regulator output, the phases being phase 1 with the first and second switches closed, phase 2 with the first switch closed and the second switch open, and phase 3 with both switches open. The first and second devices may be switches or diodes. Various embodiments are disclosed.

Abstract: In order to be able to cut short workpieces by means of a multiple blade circular sawing machine a separate depresser member is provided for each saw blade. This depresser member has a slot which extends in the longitudinal direction of this member and through which the respective saw blade projects. A depresser member is so connected to an associated displacer head that together therewith it is displaceable to a defined position and is fixable in this position. Furthermore, at least one presser roller is provided in each depresser blade on both sides of the saw blade in the sawing region and the workpiece to be sawn is pressed thereby against a conveyor chain.