A fully integrated self-calibrating transmitter/receive IC for anultrasound presence detector microsystem

A fully integrated transmitter/receiver ASIC for an ultrasound presence detection microsystem is described. The transducers consist of thermally excited silicon membranes which are fabricated using a standard silicon circuit technology plus one additional etching step. The mixed-signal chip is realized with no external components. It can be configured as either the transmitter or the receiver of the microsystem. As a transmitter, the silicon transducer is used as an electromechanical resonator to emit ultrasound at 80 kHz. In receive mode, the sensor sensitivity is automatically maximized by a self-calibrating scheme which tunes the receiver membrane resonant frequency to that of the transmitter     

Implementation of high peak-current IGBT gate drive circuits inVLSI compatible BiCMOS technology

A BiCMOS integrated gate-drive (IGD) application specific integrated circuit (ASIC) has been implemented in a 18 V, 3 μm BiCMOS technology for insulated gate bipolar transistor- (IGBT-) based intelligent power modules (IPM). It features various monitoring and control functions such as linear dV/dt feedback and master-slave control of IGBT's, and is capable of delivering 16-18 A peak current to high capacitive loads. Classic formulas on the current capability of bipolar junction transistors (BJT's), MOSFET's, and metal conductors are briefly reviewed and additional experiments are presented in the context of our application