SBASB89 May 2025 ADS117L14 , ADS117L18
PRODUCTION DATA
The sinc3 filter mode is a single-stage filter. The sinc3 filter provides several data rate options including 400SPS, 60SPS, and 50SPS for line-cycle noise rejection. 10SPS is achieved by slowing the ADC clock to 10/50 x 3.2MHz = 0.64MHz in low-speed mode. Because of the large width of the frequency response notch, excellent line-frequency NMRR and CMRR is achieved. Table 7-5 summarizes the characteristics of the sinc3 filter.
| MODE | fCLK (MHz) | OSR | DATA RATE (SPS) | –3dB FREQUENCY (Hz) | LATENCY (ms) | NMRR AT FIRST NULL (dB) | |
|---|---|---|---|---|---|---|---|
| 2% CLOCK TOLERANCE | 6% CLOCK TOLERANCE | ||||||
| Max speed | 32.768 | 26667 | 614.4 | 161.3 | 4.88 | 100 | 71 |
| High speed | 25.6 | 480 | 126 | 6.25 | |||
| Mid speed | 12.8 | 240 | 63.0 | 12.5 | |||
| Low speed | 3.2 | 60 | 15.7 | 50.0 | |||
| Max speed | 32.768 | 32000 | 512 | 134 | 5.86 | 100 | 71 |
| High speed | 25.6 | 400 | 105 | 7.50 | |||
| Mid speed | 12.8 | 200 | 252 | 15 | |||
| Low speed | 3.2 | 50 | 13.1 | 60.0 | |||
Figure 7-21 shows the frequency response of the sinc3 filter (OSR = 32000). Figure 7-22 shows the detailed response in the region of 0.9 to 1.1 · fIN / fDATA.
Figure 7-21 Sinc3 Frequency Response
Figure 7-22 Detail Sinc3 Frequency Response (OSR = 32000)