INTEGRATED LOW VOLTAGE TRANSMIT/RECEIVE SWITCH FOR ULTRASONIC IMAGING SYSTEM

• Main Authors: FISHER RAYETTE A, WODNICKI ROBERT G
• Format: Patent
• Language: English
• Published: 21.07.2005
• Edition: 7
• Subjects: ACCESSORIES THEREFOR; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USINGWAVES OTHER THAN OPTICAL WAVES; APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FORPROJECTING OR VIEWING THEM; CINEMATOGRAPHY; DIAGNOSIS; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; ELECTROGRAPHY; FOR PERFORMING MECHANICAL WORK IN GENERAL; GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL; HOLOGRAPHY; HUMAN NECESSITIES; HYGIENE; IDENTIFICATION; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; MEDICAL OR VETERINARY SCIENCE; METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICALVIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY; PERFORMING OPERATIONS; PHOTOGRAPHY; PHYSICS; SURGERY; TESTING; TRANSMISSION; TRANSPORTING

PROBLEM TO BE SOLVED: To protect a sensitive low voltage electronic circuit from high voltage pulse signals used for driving an ultrasonic transducer. SOLUTION: This low voltage transmit/receive switch (14) includes a series resistance (24) and a parallel MOSFET pair (M5, M6). The parallel MOSFETs are low voltage devices. The low voltage transmit/receive switch is placed between the output of a high voltage pulse generating circuit (M3, M4) and a receive preamplifier (16). If a dual high- and low voltage pulse generating circuits are used, low voltage pulse generating circuits (M1, M2) are connected so as to be protected from high voltage pulse signals by the low voltage transmit/receive switch. In an alternative embodiment, the low voltage pulse generating circuit and the receive preamplifier are protected from high voltage pulse signals by a high voltage transmit/receive switch (M7, M8). COPYRIGHT: (C)2005,JPO&NCIPI