ZHCSHW6B October 2017 – October 2018 ADS122C04
PRODUCTION DATA.
Table 12 shows the actual conversion times for each data rate setting. The values provided are in terms of tCLK cycles and in milliseconds.
Continuous conversion mode data rates are timed from one DRDY falling edge to the next DRDY falling edge. The first conversion starts 28.5 · tCLK (normal mode) or 105 · tCLK (turbo mode) after the START/SYNC command is latched.
Single-shot conversion mode data rates are timed from when the START/SYNC command is latched to the DRDY falling edge and rounded to the next tCLK.
Commands are latched on the eighth falling edge of SCL in the command byte.
NOMINAL DATA RATE
(SPS) |
–3-dB BANDWIDTH
(Hz) |
CONTINUOUS CONVERSION MODE(2) | SINGLE-SHOT CONVERSION MODE | ||
---|---|---|---|---|---|
ACTUAL CONVERSION TIME (tCLK)(1) | ACTUAL CONVERSION TIME (ms) | ACTUAL CONVERSION TIME (tCLK)(1) | ACTUAL CONVERSION TIME (ms) | ||
NORMAL MODE | |||||
20 | 13.1 | 51192 | 49.99 | 51213 | 50.01 |
45 | 20.0 | 22780 | 22.5 | 22805 | 22.27 |
90 | 39.6 | 11532 | 11.26 | 11557 | 11.29 |
175 | 77.8 | 5916 | 5.78 | 5941 | 5.80 |
330 | 150.1 | 3116 | 3.04 | 3141 | 3.07 |
600 | 279.0 | 1724 | 1.68 | 1749 | 1.71 |
1000 | 483.8 | 1036 | 1.01 | 1061 | 1.04 |
TURBO MODE | |||||
40 | 17.1 | 51192 | 25.00 | 51217 | 25.01 |
90 | 39.9 | 22780 | 11.12 | 22809 | 11.14 |
180 | 79.2 | 11532 | 5.63 | 11561 | 5.65 |
350 | 155.6 | 5916 | 2.89 | 5945 | 2.90 |
660 | 300.3 | 3116 | 1.52 | 3145 | 1.54 |
1200 | 558.1 | 1724 | 0.84 | 1753 | 0.86 |
2000 | 967.6 | 1036 | 0.51 | 1065 | 0.52 |
Although the conversion time at the 20-SPS setting is not exactly 1 / 20 Hz = 50 ms, this discrepancy does not affect the 50-Hz or 60-Hz rejection. The conversion time and filter notches vary by the amount specified in the Electrical Characteristics table for oscillator accuracy.