Control logic and latching to the Faraday Cup experiment on the wind laboratory

A satellite-mounted instrument has been developed to measure the energy spectrum of the solar proton flux in the solar wind. The instrument consists of a sensor (Faraday Cup), an analog signal processing chain, a high-voltage modulator, and a digital section, which is described. The functions of the digital section are (a) to interface with the main processor, (b) to provide the logic signals to the analog circuitry, (c) to deliver the necessary bit pattern to the high-voltage modulator, (d) to provide the calibration mode signals when necessary, and (e) to synchronize the sequence of events at the beginning of every spacecraft rotation. As with all space projects, primary concerns beyond the logical functionality consisted of circuit power consumption, instrumental mass, radiation tolerance levels, stability with respect to temperature, and relative ease of component procurement. The NASA WIND spacecraft will carry the experiment and launch in December of 1992