Abstract: A current bias, current sense magneto-resistive preamplifier for a hard disk drive and related methods preferably includes an MR sensor responsive to a current bias for sensing a change in magnetic data flux and responsively providing a change in electrical resistance. A preamplifying circuit is preferably connected to the MR sensor for providing the current bias thereto and for amplifying a detected change in electrical resistance. The preamplifying circuit includes a sensor biasing circuit for providing the current bias to the MR sensor and an amplifying output circuit for providing an amplified output signal representative of the detected change in current bias to the MR sensor. The sensor biasing circuit preferably includes a current source, a first amplifying circuit connected to the MR sensor for sensing the change in electrical resistance therefrom, and a second amplifying circuit having a first input connected to the first amplifying circuit and a second input connected to the current source.
Abstract: This invention is a method for boosting the voltage level of a wordline in a DRAM having bitlines, sense amplifiers, isolation devices, bitline loads, an X decoder device and a Y select device. In the preferred method, when the wordline level reaches VDD, the decoder is disabled causing the wordline to stay at the VDD level. The sensing amplifier is also caused to be isolated so as to allow the wordline voltage to track the bitline voltage through capacitive coupling across the access MOSFET of the memory cell being read or written to. As a result, the wordline voltage is increased to a supervoltage as the bitline voltage increases. After the supervoltage is reached on the wordline, the sensing amplifier is connected causing feedback from the amplifier to drive the wordline voltage toward the VDD level and the disabled bit toward GND during this time. At the end of the wordline clock signal, the voltage is at GND and each of the bitlines are returned to their neutral mid-voltage level.
Abstract: An integrated circuit capacitor ladder which uses a differential pair of capacitors for each step in the ladder. By pairing a square with a rectangle of equal perimeter, the contributions of edge and corner elements can be canceled out. This adds area and complexity, but greatly increases the precision of scaling.