Portable autonomous device for the detection and recording of randomly occurring phenomena of short duration

Claim 1

A portable autonomous device for detecting and recording, during relatively long periods of time, physical quantities representative of randomly occurring phenomena of short duration, said device using at least one first measurement chain comprising a sensor sensitive to a physical quantity to be monitored, an analog-to-digital converter capable of supplying a digital signal of said physical quantity detected by the sensor, a threshold comparator designed to emit an activation signal when the quantity detected by the sensor meets a threshold condition, and a microcontroller connected to a clock circuit by means of a logic reactivation circuit, said microcontroller effecting operating sequences during each of which it takes samples of said digital signal, associates these samples with information enabling them to be time-stamped and memomrizes said samples, along with their associated information, in a memory that can be accessed by a read module separate from said device, by means of suitable communication means, said clock circuit operating permanently and said logic reactivation circuit being designed to apply to said microcontroller said clock signal produced by the clock circuit during first and second limited periods of time between which said microcontroller is stopped, said first periods of time comprising one of said operating sequences and starting when said threshold comparator emits said activation signal, and said second periods of time being triggered subsequent to transmission by said logic reactivation circuit of a reactivation signal which causes a furtive reactivation of said microcontroller for performing a time count, said comparator being external with respect to said microcontroller and said clock circuit being integrated with said reactivation circuit into an ASIC.