Abstract: A noise dosimeter with capability to rapidly predict noise exposure over an extended time period based on a measurement of short duration. Either an acoustic or an electrical earphone adapter provides a convenient means to connect the noise dosimeter to an external sound source. A direct input jack operable to receive at least one audio signal provides a signal to an RMS detector, which provides a DC signal to a two-stage amplifier circuit. The outputs of the amplifiers are provided to a processor having multiple A/D channels. The processor calculates accumulated noise doses and drives a display, which in one embodiment includes a panel of light-emitting diodes. In one embodiment, the dosimeter includes functionality for control of external devices such as sound boards.

Abstract: A personal noise dosimeter having functionality for increasing the dynamic range of the device. A microphone provides a signal to an RMS detector, which provides a DC signal to a two-stage amplifier circuit. The outputs of the amplifiers are provided to a processor having multiple A/D channels. The processor calculates accumulated noise doses and drives a display, which in one embodiment includes a panel of light-emitting diodes. A current source injects current into the output of the RMS detector to reduce performance degradation. Functionality detects and accounts for voltage offsets in the dosimeter. The microphone is turned off during offset determination. In one embodiment, the dosimeter includes functionality for control of external devices such as sound boards.