Abstract: A method for real-time, high-density physiological data collection includes automatically measuring, by a wearable device, one or more physiological parameters during each of a plurality of measurement periods, and upon conclusion of a measurement period, for each of the plurality of measurement periods, automatically transmitting by the wearable device data representative of the physiological parameters measured during that measurement period, to a server, the server configured to develop a baseline profile based on the data transmitted by the wearable device for the plurality of measurement periods. The measurement periods may extend through a plurality of consecutive days, and each of the consecutive days may include multiple measurement periods. At least some of the physiological parameters are measured by non-invasively detecting one or more analytes in blood circulating in subsurface vasculature proximate to the wearable device.

Abstract: A potentiostat includes a voltage regulator, a current mirror, a capacitor, a comparator, a current source, and a counter. The voltage regulator maintains a voltage on a working electrode of an electrochemical sensor. The current mirror develops a mirror current that mirrors an input current from the working electrode. The capacitor is alternately charged by the mirror current, causing the capacitor voltage to increase at a rate related to the current's magnitude, and discharged by a control current, causing the capacitor voltage to decrease. The comparator outputs a waveform that includes upward and downward transitions based on the variations of the capacitor voltage. The current source produces the control current based on the waveform. The counter counts the number of upward or downward transitions in the waveform during a predetermined sampling period to produce a digital output. The digital output is representative of the magnitude of the input current.