Hand-held test meter with time-multiplexed phase detection

摘要

A hand-held test meter for use with an analytical test strip in determining an analyte in a fluid sample includes a housing retaining a microcontroller block and a phase-shift-measurement block. The measurement block includes a signal-generation sub-block that provides an excitation voltage signal; an interface sub-block that receives the analytical test strip and permits applying the voltage excitation signal to the test strip to provide a resultant current signal; a transimpedance conversion sub-block that receives the resultant current signal and provides a resultant voltage signal; and a phase detector responsive to the resultant voltage signal and a reference signal. The microcontroller block successively provides 0°- and 90°-phase reference signals as the reference to the phase detector to measure in-phase and quadrature components and determine a phase shift corresponding to a fluid sample in the received analytical test strip.