Ultra-low-power pulse oximeter implemented with an energy-efficient photoreceptor

摘要

An energy-efficient photoreceptor apparatus and a transimpedance amplifier apparatus having high energy-efficiency and low power consumption of which are achieved through multiple distributed gain amplification stages, adaptive loop gain control circuitry and unilateralization, thereby enabling fast and precise performance over a wide range of input-current levels. The high-energy efficiency, robust feedback stability and performance of the present invention can be utilized to achieve sub-milliwatt pulse oximeters and may be employed in other current-to-voltage amplification and conversion applications. The use of analog processing on the outputs of the photoreceptor apparatus also helps lower the overall power of pulse oximeters.