JAJSTV7 March 2024 DAC39RF10-SEP , DAC39RF10-SP , DAC39RFS10-SEP , DAC39RFS10-SP
PRODMIX
The output of the summation block or the non-interpolated input signal can optionally be interpolated by 2x by the DES interpolator to double the sample rate for DES2XL and DES2XH output modes. The DES interpolator has a passband bandwidth of 80%, stopband attenuation of 54dB and ripple less than ±0.02dB. The DES interpolator can operate as high pass (DES2XH) or low pass (DES2XL) with an inverted spectrum. The DES2X filter coefficients are listed in Table 7-14 and the responses are shown in Figure 8-150, with the passband ripple for DES2XL shown in Figure 7-49.The sample rate after interpolation is 2*fCLK due to having samples on both the rising and falling edges, so the x-axis in Figure 8-150 covers the Nyquist zone.
Filter | Coefficients (center tap is in bold) |
---|---|
DES2X | [-9 0 19 0 -39 0 70 0 -122 0 211 0 -403 0 1293 2048 1293 0 -403 0 211 0 -122 0 70 0 -39 0 19 0 -9 ]*2-11 |