Abstract: A time stress measurement device is provided for use in diverse electronic and electromechanical system. The TSMD collects environmental data applied to a system, collects event data experienced by the system, time-stamps the environmental and event data, compares the environmental data to various preset thresholds, and stores the time-stamped environmental data and time-stamped event data. The data is stored in various data structures, including recent environmental data, historical environmental data, peak environmental data, and event signature data. The environmental data and event data can be retrieved by maintenance personnel to isolate and analyze system faults and failures. The device can further be capable of sending a test signal to the system in order to determine whether the system is operating properly.

Abstract: A microprocessor-based system includes a central processing unit (CPU) and a CPU memory coupled by a CPU bus. A DMA sampler is coupled to the CPU, the CPU memory and the CPU bus. The DMA sampler includes sampling circuitry which is implemented as a finite state machine to maintain a substantially exact sampling rate on at least one analog input signal provided to the DMA sampler. The DMA sampler also includes DMA circuitry implemented as a data flow machine, which requests bus mastership from the CPU when samples obtained by the DMA sampler are available for transfer to the CPU memory. In response to the request, the CPU relinquishes bus mastership to the DMA sampler which provides the sample to the CPU memory and returns bus mastership to the CPU.

Abstract: An integrated semiconductor chip includes, integral to its substrate, a thermal sensing circuit formed from an array of transistors connected together in a stacked array so as to multiply the inherent effects of temperature on output voltage. A series of gates is connected to the output of the transistor array. A reference voltage is applied to the transistor array, and the inherent temperature-variable output of the array is then applied to the gates. The gates change states at known temperatures and voltages, so that the digital state output of each gate indicates whether the substrate temperature is greater than or less than the switching temperature associated with that gate. By sensing gate output, the chip itself or an external device can determine the temperature of the substrate within a certain range. When the temperature is outside the safe operating range for the chip, the chip or an external device takes steps to prevent unsafe operation.