LIGHT-TO-FREQUENCY CONVERTER ARRANGEMENT AND METHOD FOR LIGHT-TO-FREQUENCY CONVERSION

摘要

A method for light-to-frequency conversion comprises generating a photocurrent (IPD) by means of a photodiode (11) and converting the photocurrent (IPD) into a digital comparator output signal (LOUT) in a charge balancing operation depending on a first clock signal (CLK1). From the digital comparator output signal (LOUT) an asynchronous count (C1) is determined and comprises an integer number of counts depending on the first clock signal (CLK1). From the digital comparator output signal (LOUT) a fractional time count (C2) is determined and depends on a second clock signal (CLK2). Finally, from the asynchronous count (C1) and from the fractional time count (C2) a digital output signal (ADC-COUNT) is calculated which is indicative of the photocurrent generated by the photodiode (11). The method may be carried out by an exemplary light-to-frequency converter equipped with a photodiode.