MilliWatt Modules Using Parallel Circuitry

65312 Future space missions, involving the powering of multiple remote sensors and periodic transmission of collected data back to earth, require redundant or parallel circuitry within very small and very reliable thermoelectric power supplies of 40 mW to 500 mW size. Space allocation and weight constraints require the solution of the redundancy problem within current envelopes. By reducing the size and dimensional tolerances of the elements used in the thermoelectric module, a parallel circuit will be incorporated into the module design without increasing the module size. Phase I: (1) demonstrated new tooling that results in near-perfect alignment of the smaller legs in a matrix module with parallel circuitry, (2) demonstrated semi-automation of gold tab spot welding of the smaller legs and a gold deposition system for element connections, and (3) identified and analyzed two parallel circuit designs. Phase II will (1) further develop the matrix fabrication process for near perfect alignment, (2) continue the development of both the gold deposition process and the parallel gap spot welding at gold tabs, and (3) fabricate and evaluate modules with the two (serpentine and cluster) parallel circuitry designs. Commercial Applications and Other Benefits as described by the awardee: The small thermoelectric modules should have use in powering remote sensors for the wireless transmission of data. Early warning and protection of critical, expensive, and safety related equipment should be achieved.