Abstract: An integrated substrate comprising a heatsink base, and a multilayer circuit board bonded thereto, the multilayer circuit board having the capability to interconnect both power and control semiconductor elements and efficiently dissipate heat therefrom. A thermally conductive and electrically insulating bonding material having excellent thermal properties bonds the multilayer circuit board to the base. One or more thick electrically conductive foil patterns are formed intermediate the top surface of the circuit board and the heatsink base, the thick foil pattern(s) adapted to interconnect high power semiconductor elements. Also included intermediate the top surface of the circuit board and the heatsink base are one or more interconnect patterns which wire control semiconductor elements.

Abstract: There is disclosed herein a wristwatch size cardiac monitoring apparatus which is worn on the wrist of one arm. A conductive material housing acts as one electrode when held firmly in contact with the wrist of the arm on which it is worn. A finger of the other limb is placed on a receiving electrode of the casing which acts as the second electrode. Together, these two electrodes provide a Lead I electrocardiac signal to electronics within the housing. The second electrode consists of a metal layer on which is placed a dielectric material and when the finger is placed on top of the dielectric material, a capacitor is formed and the electric signal on the finger is transferred to the metal layer. Additionally, there is described circuitry which is used to operate the rate monitor. This circuitry includes means for detecting a QRS complex and for causing a count in beats per minute to be displayed, manifesting the heartbeat rate.