Abstract: A pipelined analog-to-digital converter in which signal value samples are represented differentially by pairs of charges and which uses charge-coupled-devices (CCDs) for delay and arithmetic operations on the charges is presented. In the pipeline, each successive stage resolves an equal or smaller charge difference. After a certain number of pipeline stages, the common-mode component of the signal-charge pair is reduced. The pipeline stages following this common-mode-charge reduction stage have a reduced charge capacity and size, allowing more sensitive charge comparison. The result is improved A/D converter resolution and reduced power consumption.

Abstract: A phased array ultrasound scanning apparatus includes a one-dimensional (1-D) array of ultrasound transducer elements having transmit and receive elements. The 1-D array is responsive to a transmitter configured to energize the transmit elements for generating a transmit acoustic beam directed into a region of interest. A receive beamformer, operatively connected to the 1-D array, synthesizes receive beams, in response to echoes of the transmit acoustic beam received from the region of interest. The receive beamformer includes analog random access memory (ARAM) delay elements configured to delay signals received from the receive elements and provide the delayed signals on an output of the receive beamformer as a beamformed RF output. The beamformed RF output is suitable for use in forming an image of the region of interest.

Abstract: A portable, configurable and scalable ultrasonic imaging system uses a phased ultrasonic transducer array coupled to a portable, configurable and scalable ultrasonic processor to develop ultrasonic images. When used in conjunction with a sector phased array, the portable, configurable and scalable ultrasonic imaging system uses a processing channel associated with each element in the transducer array to develop the ultrasonic image. When used with a linear or curved linear transducer array, the portable, configurable and scalable ultrasonic processor uses fewer processing channels than transducer elements to develop the ultrasonic image. Since the portable, configurable and scalable ultrasonic processor is scalable, it is able to use a variety of processors, software and transducer arrays to develop a number of different ultrasonic output images.

Abstract: A simple, low cost ultrasound beamforming system uses an analog random access memory (RAM) element for each beamforming channel. The system includes a processor and an ultrasonic transducer array. The ultrasonic transducer array includes a plurality of transducer elements, each transducer element associated with one of a plurality of channels. The system also includes a beamformer adapted to receive an output signal from each of the plurality of transducer elements, and a delay element located in the beamformer and associated with each of the channels, where the delay element comprises an analog random access memory element.

Abstract: A micro-machined ultrasonic transducer (MUT) having aperture, elevation and apodization controlled by apparatus located on the same substrate as the transducer, or by bias voltage control applied to MUT elements, allows for an efficient and compact ultrasonic probe. The control apparatus may take the form of field effect transistors (FET's), micro-machined relays, or doped regions on the substrate, or any other apparatus that may be located on the same substrate as that of the transducer, or by bias voltage sources connected to the MUT elements.

Abstract: A delay generator for a beamformer in a phased array ultrasound imaging system is provided. The beamformer processes received signals from an array of transducer elements to form a receive beam. The beamformer includes a delay generator corresponding to each transducer element for delaying the received signal. The delay generator includes a delay unit and a delay controller. The delay is variable in response to a change delay signal supplied by the delay controller at discrete times during reception of ultrasound energy. According to one feature of the invention, the delay represents an exact solution, within the quantization error of the delay unit, to the delay equation for the delay at a given steering angle, transducer element and focal depth. According to another feature of the invention, the delay controller generates a change delay signal that steers the receive beam to a dynamically variable steering angle and dynamically focuses the receive beam during reception of ultrasound energy.

Abstract: An ultrasound transducer apparatus for use with an ultrasound imaging system which includes signal transmission and signal receiving circuitry coupled to the transducer through a cable. The transducer apparatus includes a transducer for converting ultrasonic energy into electronic signals and a variable gain amplifier circuit having an input coupled to the transducer and an output coupled to the cable for amplifying the electronic signals at a gain determined by a gain control signal from the imaging system. The transducer apparatus is typically hand-held, and the variable gain amplifier circuit is preferably mounted in the hand-held unit in close proximity to the transducer element. The variable gain amplifier circuit preferably includes a preamplifier and a variable gain amplifier. Preferably, the transducer is a transducer array including a plurality of transducer elements, each having a preamplifier and a variable gain amplifier associated with it.

Abstract: A bipolar memory circuit having a storage cell including a single bipolar transistor whose collector-base junction acts to provide a capacitor for capacitive charge storage; a charging means coupled to the emitter or collector to charge the collector-base capacitor of the transistor, the charged condition of that capacitor indicating a first memory state; a discharging means including at least one PN junction series coupled with the base-collector junction of the transistor, the discharging means including an input means coupled through the PN junction for discharging the charge stored in the collector-base junction without need for avalanching the transistor, the discharged condition of the capacitor being indicative of the opposite state of the memory storage cell; a pulse supply for applying sensing pulses between the emitter and the collector electrodes of the transistor; and a signal-detecting circuit at one of the collector or emitter electrodes of the transistor for determining what state the memory ce

Abstract: A double-diffused, lateral transistor structure is fabricated utilizing an etch resistant mask to provide self-aligning positional accuracy for formation of active areas of the transistor. The lateral structure includes semiconductor material having at least one substantially flat surface, and the structure includes at least one region of insulating material formed adjacent the flat surface, the top surface of the insulating material being substantially coplanar with said one surface. A collector is formed in the semiconductor material adjacent first portions of both the flat surface and the insulating material, while an emitter is formed in the semiconductor material adjacent second portions of both the flat surface and the insulating material. A base separates the collector from the emitter.