Pulse oximetry sensor switchover

摘要

Switchover of a filtered and unfiltered pulse oximetry sensor is provided with gain controlled amplifiers controlled by separate gain control voltages that may change in opposite directions over a period of time. The outputs of the gain controlled amplifiers may be coupled to voltage-to-current converters whose outputs may be coupled in parallel. The parallel coupled outputs of the voltage-to-current converters may produce a current signal representative of the output of the gain controlled amplifier having the highest gain/signal.