SBASAI6 September 2023 ADC32RF52
PRODUCTION DATA
The ADC32RF52 provides up to four digital down converters per ADC channel (see Figure 7-20). The decimation filters provide a flexible option to cover a wide range of instantaneous bandwidths (IBW) as shown in Table 7-15. Single band decimation supports a wide bandwidth up to complex decimation by 4x while up to four narrow band channels with up to 128x complex decimation are supported in quad band decimation mode.
# of DDCs | Minimum Complex Decimation | Maximum Complex Decimation |
---|---|---|
1 | 4 | 128 |
2 | 8 | 128 |
4 | 16 | 128 |
The decimation filter can be configured to two different operating modes:
During the complex mixing operation the digital output is reduced by 6-dB. This reduces the fullscale from 0-dBFS to -6-dBFS. This 6-dB change applies to signals and noise and thus no dynamic range is lost.
Since the JESD204B interface is common across ADC channel A and B, the decimation ratio as well as the # of DDCs/ADC has to be the same across channels A and B.
By default, the output of values of the decimation filter are rounded to 16-bit resolution. T avoid quantization noise limitation when using high order of decimation (that is /64 or /128), a special 20-bit output mode can be enabled (see 20-bit mode).
Table 7-16 provides an overview of the available complex decimation settings and resulting complex and real output bandwidths.
Decimation Factor N (complex) | Complex Output Bandwidth per DDC | FS = 1.5 Gsps | Real Output Bandwidth per DDC | FS = 1.5 Gsps | ||
---|---|---|---|---|---|---|
Complex Output Rate per DDC | Complex Output Bandwidth per DDC | Real Output Rate per DDC | Real Output Bandwidth per DDC | |||
4 | 0.8 x FS / 4 | 375 Msps | 300 MHz | 0.4 x FS / 4 | 375 Msps | 150 MHz |
8 | 0.8 x FS / 8 | 187.5 Msps | 150 MHz | 0.4 x FS / 8 | 187.5 Msps | 75 MHz |
16 | 0.8 x FS / 16 | 93.75 Msps | 75 MHz | 0.4 x FS / 16 | 93.75 Msps | 37.5 MHz |
32 | 0.8 x FS / 32 | 46.875 Msps | 37.5 MHz | 0.4 x FS / 32 | 46.875 Msps | 18.75 MHz |
64 | 0.8 x FS / 64 | 23.4375 Msps | 18.75 MHz | 0.4 x FS / 64 | 23.4375 Msps | 9.375 MHz |
128 | 0.8 x FS / 128 | 11.71875 Msps | 9.375 MHz | 0.4 x FS / 128 | 11.71875 Msps | 4.6875 MHz |