AD6672
MEMORY MAP REGISTER DESCRIPTION
For more information on functions controlled in Register 0x00
to Register 0x20, see the AN-877 Application Note, Interfacing
to High Speed ADCs via SPI.
NSR Control (Register 0x3C)
Bits[7:4]—Reserved
Bits[3:1]—NSR Mode
Bits[3:1] determine the bandwidth mode of the NSR. When
Bits[3:1] are set to 000, the NSR is configured for 22% bandwidth
mode, which provides enhanced SNR performance over 22% of
the sample rate. When Bits[3:1] are set to 001, the NSR is
configured for 33% bandwidth mode, which provides enhanced
SNR performance over 33% of the sample rate.
Data Sheet
Bit 0—NSR Enable
The NSR is enabled when Bit 0 is high and disabled when Bit 0
is low.
NSR Tuning Word (Register 0x3E)
Bits[7:6]—Reserved
Bits[5:0]—NSR Tuning Word
The NSR tuning word sets the band edges of the NSR band. In
22% bandwidth mode, there are 57 possible tuning words; in
33% bandwidth mode, there are 34 possible tuning words. In
either mode, each step represents 0.5% of the ADC sample rate.
For the equations that are used to calculate the tuning word
based on the bandwidth mode of operation, see the Noise
Shaping Requantizer section.
Rev. C | Page 28 of 30