Abstract: An apparatus is disclosed that provides an estimate of the semiconductor junction temperature of a semiconductor device as a function of the electrical current flowing across the corresponding semiconductor junction. The apparatus includes a current sensor that samples and measures the current flowing across the semiconductor junction and provides an output signal indicative of the measured value to a current-to-temperature converter. The current-to-temperature converter estimates the temperature of the semiconductor junction using equations that include constants empirically derived for the particular device configuration including cooling and mounting methods used with it. The current-to-temperature converter provides an output temperature signal that is compared to a predetermined temperature threshold value, and in the event that the output temperature signal exceeds the predetermined temperature threshold value, an alarm signal is set.

Abstract: An apparatus is disclosed that provides an estimate of the semiconductor junction temperature of a semiconductor device as a function of the electrical current flowing across the corresponding semiconductor junction. The apparatus includes a current sensor that samples and measures the current flowing across the semiconductor junction and provides an output signal indicative of the measured value to a current-to-temperature converter. The current-to-temperature converter estimates the temperature of the semiconductor junction using equations that include constants empirically derived for the particular device configuration including cooling and mounting methods used with it. The current-to-temperature converter provides an output temperature signal that is compared to a predetermined temperature threshold value, and in the event that the output temperature signal exceeds the predetermined temperature threshold value, an alarm signal is set.

Abstract: An antenna for transmitting electromagnetic signals having a frequency less than 500 Hz includes a beam of dielectric material and a conductive sheet wound in a helical pattern around the beam of dielectric material. The antenna further includes a core fabricated from a silicon and iron alloy, the cote disposed between the beam of dielectric material and the conductive sheet. With such an arrangement, a magnetic dipole antenna is provided capable of providing a magnetic moment of approximately 10.sup.6 to 10.sup.7 Am.sup.2.