Self-modulated voltage reference

摘要

A self-modulated voltage reference circuit may generate a reference voltage by receiving an internal reference voltage of a programmable device at a first input of a comparator block of the programmable device, receiving a feedback voltage at a second input of the comparator block, generating a pulse density modulated (PDM) signal based on a difference between the reference voltage and the feedback voltage, outputting the PDM signal at a digital output pin of the programmable device, and filtering the PDM signal to generate the output reference voltage.

主权项

1. A circuit, comprising:
a first digital output pin of a programmable device; a second digital output pin of the programmable device; a comparator block within the programmable device, the comparator block comprising a first input, a second input, and a comparator output that is coupled to the first digital output pin and to the second digital output pin; an internal reference voltage source that is coupled to the first input of the comparator block; an analog input pin of the programmable device, wherein the analog input pin is coupled to the second input of the comparator block; a digital density signal generator within the programmable device, the digital density signal generator being coupled to the first digital output pin; and a feedback network coupled between the second digital output pin and the analog input pin.