Friday, 22 July 2005
A.Farina, L.Tronchin
16/86
ADC (Analog to Digital Converter) 5
Bitstream Converters
• The idea arises from oversampling: increasing sample frequency it would be possible to increase amplitude resolution (bits)
• Sample rate: 2.88 MHz and 1 bit resolution: dividing to 2 for 6 time is equivalent to CD audio sample rate, but only with 7 bits!
• In order to enhance high freq. resolution, a proper noise shaping of high order is required, suitable for static (non transient) signals.
• Below 88 Hz the Bitstream converters outperform PCM conv.