An analog-to-digital converter circuitry, an integrated circuit device, a photoplethysmogram detector, a wearable device and a method for analog-to-digital conversion. Interuniversity Microelectronics Centre
An analog-to-digital converter, ADC, circuitry, comprises: an integrator (102; 202) connected to a capacitor (110; 210a, 210b), the integrator (102; 202) being configured to switch between integrating an analog input signal for ramping an integrator output and integrating a reference input signal for returning integrator output towards a threshold; a comparator (120; 220) for comparing integrator output to the threshold; and a timer (150; 250) for determining a time duration during which the reference input signal is integrated, the time duration providing a digital representation of an ...