Ng V.W.,Volterra |
Sanders S.R.,University of California at Berkeley
IEEE Transactions on Power Electronics | Year: 2013
The traditional inductor-based buck converter has been the default design for switched-mode voltage regulators for decades. Switched capacitor (SC) dc-dc converters, on the other hand, have traditionally been used in low-power (<10 mW) and low conversion ratio (<4:1) applications where neither regulation nor efficiency is critical. This study encompasses the complete successful design, fabrication, and test of a CMOS-based SC dc-dc converter, addressing the ubiquitous 12-1.5 V board-mounted point-of-load application. In particular, the circuit developed in this study attains higher efficiency (92% peak, and >80% over a load range of 5 mA to 1 A) than surveyed competitive buck converters, while requiring less board area and less costly passive components. The topology and controller enable a wide input range of 7.5-13.5 V. Controls based on feedback and feedforward provide tight regulation under worst case line and load step conditions. This study shows that the SC converter can outperform the buck converter, and thus, the scope of SC converter application can and should be expanded. © 1986-2012 IEEE.
Volterra | Date: 2014-03-14
A voltage regulator has an input terminal and a ground terminal. The voltage regulator includes a high-side device, a low side device, and a controller. The high-side device is coupled between the input terminal and an intermediate terminal. The high-side device includes first and second transistors each coupled between the input terminal and the intermediate terminal, such that the first transistor controls a drain-source switching voltage of the second transistor. The low-side device is coupled between the intermediate terminal and the ground terminal. The controller drives the high-side and low-side devices to alternately couple the intermediate terminal to the input terminal and the ground terminal.
Volterra | Date: 2014-03-17
An inductor includes a core formed of a magnetic material and a foil winding wound at least partially around or through at least a portion of the core. A first end of the winding extends away from the core to form an extended output tongue configured and arranged to supplement or serve as a substitute for a printed circuit board foil trace. A second end of the winding forms a solder tab. At least a portion of the extended output tongue and the solder tab are formed at a same height relative to a bottom surface of the core. Another inductor includes a core formed of a magnetic material, a winding wound at least partially around or through at least a portion of the core, and a ground return conductor attached to the core. The core does not form a magnetic path loop around the ground return conductor.
Volterra | Date: 2015-07-13
An integrated circuit includes a semiconductor die including one or more switching circuits, a magnetic core having length and width, first and second metallic leads, and integrated circuit packaging material. The first metallic lead forms a first winding turn around a portion of the magnetic core, and the first metallic lead is electrically coupled to the semiconductor die. The second metallic lead forms a second winding turn around a portion of the magnetic core. The first and second winding turns are offset from each other along both of the width and length of the magnetic core. The integrated circuit is, for example, included in an integrated electronic assembly.
Volterra | Date: 2015-06-29
A semiconductor package can include a semiconductor die having an integrated circuit, a first die surface, and an opposite second die surface. A packaging can be attached to the die and have a holder surface opposite the first die surface. A heat spreader can be configured to cover the second die surface and the packaging surface and can be attached thereto by a layer of adhesive positioned between the heat spreader and the semiconductor die. A semiconductor package array can include an array of semiconductor dies and a heat spreader configured to cover each semiconductor die. A conductive lead can be electrically connected to the integrated circuit in a semiconductor die and can extend from the first die surface. Manufacturing a semiconductor package can include applying thermally conductive adhesive to the heat spreader and placing the heat spreader proximate the semiconductor die.