Abstract: A resistor string that may have two resistor matrices laid out back-to-back with selected or all nominally equipotential nodes of the two matrices being interconnected. In certain applications, the matrix may have switch connections at each node, with the second matrix being an inactive matrix that may have the same number or different number, typically fewer resistors than the first matrix. In another embodiment, separate matrices may be used, and the inactive matrix may be smaller and have fewer resistors of a lower value to minimize the effect of gradients across the substrate. Preferred matrices and node connection switch configurations, as well as various embodiments of these and other features of the invention are disclosed.

Abstract: Continuous linear regulated zero dropout charge pump with high efficiency load predictive clocking scheme AND method. The method of pumping charge includes amplifying the difference between a feedback signal from the charge pump output and a reference, and alternately switching between: a) coupling a first flying capacitor between first and second power supply terminals, and coupling a second flying capacitor between the amplified difference and the charge pump output; and b), coupling the second flying capacitor between first and second power supply terminals, and coupling the first flying capacitor between the amplified difference and the charge pump output. Preferably the switching is done before the amplifier saturates. Various alternate embodiments and method and apparatus for starting the charge pump are described.

Abstract: A low power, high speed D type flip flop is disclosed. The D type flip flop uses four inverters and four transmission gates to store and output the data states. The flip flop comprises two memory elements wherein each memory element is made up of a transmission gate and two inverters. Each of the four inverters contained in the flip flop is referred to as a bypass current limiting inverter. Each of the four inverters contains biasing circuitry to limit current flow and thereby save power. Additionally, each inverter has switching circuitry that enables the current limiting features to be automatically and advantageously bypassed thereby allowing for large currents and fast response times whilst simultaneously retaining the low power performance.

Abstract: A resistor string that may have two resistor matrices laid out back-to-back with selected or all nominally equipotential nodes of the two matrices being interconnected. In certain applications, the matrix may have switch connections at each node, with the second matrix being an inactive matrix that may have the same number or different number, typically fewer resistors than the first matrix. In another embodiment, separate matrices may be used, and the inactive matrix may be smaller and have fewer resistors of a lower value to minimize the effect of gradients across the substrate. Preferred matrices and node connection switch configurations, as well as various embodiments of these and other features of the invention are disclosed.

Abstract: Enhanced linearity, low switching perturbation resistor string matrices. The resistor strings are arranged in an array of a plurality of rows of resistive elements and electrically arranged with rows equally spaced above and below the physical centerline of the array being coupled together in an opposite sense. Preferably also physically adjacent rows are equally spaced from the center of the electrical order of rows. This connection prevents accumulation of errors due to vertical and horizontal resistance gradients over the array. Also node selection by controlling node select transistors coupled to column select lines to select one node in each row, and also controlling row select transistors to select the row of the desired node minimizes settling time after a tap change by inducing equal and opposite voltage changes at points close together along the resistor string, whether in the array of the present invention or in the snake configuration.

Abstract: Enhanced linearity, low switching perturbation resistor string matrices. The resistor strings are arranged in an array of a plurality of rows of resistive elements and electrically arranged with rows equally spaced above and below the physical centerline of the array being coupled together in an opposite sense. Preferably also physically adjacent rows are equally spaced from the center of the electrical order of rows. This connection prevents accumulation of errors due to vertical and horizontal resistance gradients over the array. Also node selection by controlling node select transistors coupled to column select lines to select one node in each row, and also controlling row select transistors to select the row of the desired node minimizes settling time after a tap change by inducing equal and opposite voltage changes at points close together along the resistor string, whether in the array of the present invention or in the snake configuration.

Abstract: Segmented resistor string digital-to-analog converters using a resistor string primary converter segment and a current source secondary. The primary converter segment provides conversion of the most significant bits to an analog voltage form and the current source provides conversion of the least significant bits to an analog current form. An output circuit combines the two into a single analog output. Various embodiments are disclosed.