Reference Generation for A/D Converters

An analog-to-digital converter (ADC) compares the input voltage V
_in
with a reference voltage REF to convert it into a digital word. The reference source must be able to drive the ADCs reference input; it needs to provide low noise, should be adjustable, stable over temperature and supply voltage and should not require external components. A novel scheme was developed and implemented in a 12bit 2MSPS SAR converter.