8.3.5 Digital Filter

The device uses a linear-phase finite impulse response (FIR) digital filter that performs both filtering and decimation of the digital data stream coming from the modulator. The digital filter is automatically adjusted for the different data rates and always settles within a single cycle. The frequency responses of the digital filter are illustrated in Figure 45 to Figure 53 for different output data rates. The filter notches and output data rate scale proportionally with the clock frequency. The internal oscillator can vary over temperature as specified in the Electrical Characteristics table. The data rate or conversion time, respectively, and consequently also the filter notches vary proportionally.

Figure 45. Filter Response
(Normal Mode, DR = 20 SPS)

Figure 47. Filter Response
(Normal Mode, DR = 45 SPS)

Figure 46. Detailed View of the Filter Response
(Normal Mode, DR = 20 SPS)

Figure 48. Filter Response
(Normal Mode, DR = 90 SPS)

Figure 49. Filter Response
(Normal Mode, DR = 175 SPS)

Figure 51. Filter Response
(Normal Mode, DR = 600 SPS)

Figure 53. Filter Response
(Turbo Mode, DR = 2 kSPS)

Figure 50. Filter Response
(Normal Mode, DR = 330 SPS)

Figure 52. Filter Response
(Normal Mode, DR = 1 kSPS)