JAJSLC0 March 2024 ADC3683-SP
PRODMIX
The ADC3683-SP includes an optional on-chip digital down conversion (DDC) decimation filter that can be enabled via SPI register settings. Supporting complex decimation by 2, 4, 8, 16 and 32 using a digital mixer and a 32-bit numerically controlled oscillator (NCO) as shown in Figure 7-17.
Supporting a mode with real decimation where the complex mixer is bypassed (NCO is set to 0 for lowest power consumption) and the digital filter acts as a low pass filter.
Internally, the decimation filter calculations are performed with a 20-bit resolution to avoid any SNR degradation due to quantization noise limitation. The Output Formatter truncates to the selected resolution prior to outputting the data on the digital interface.