ZHCSNS4C April 2021 – September 2022 ADS127L11
PRODUCTION DATA
The ADC provides two operational speed modes (high speed and low speed) that allow trade-offs between ADC resolution, power consumption, and signal bandwidth. Low-speed mode operates the modulator at 1/8th speed for decreased device power consumption and, as a result, the output data rates are reduced by 1/8th. The programmable oversampling ratio (OSR) determines the output data rate and associated signal bandwidth, and therefore also determines the total noise performance. Increasing the OSR lowers the signal bandwidth and total noise by averaging more samples from the modulator to yield one conversion result.
The wideband filter provides data rates up to 400 kSPS in high-speed mode and 50 kSPS in low-speed mode. The low-latency sinc4 filter provides data rates up to 1.067 MSPS in high-speed mode and up to 133 kSPS in low-speed mode. The low-latency filter provides the options of sinc4, sinc4 + sinc1, sinc3, and sinc3 + sinc1 configurations.
Table 7-1 through Table 7-5 summarize the noise performance and signal bandwidth of the various filter modes. Noise performance is shown with 1x input range and a 4.096-V reference voltage. In comparison, decreasing the reference voltage to 2.5 V decreases dynamic range by 4 dB (typical). Operation in 2x input range and a 2.5-V reference voltage decreases dynamic range by 3 dB (typical) compared to 1x input range and 4.096-V reference voltage operation.
The noise data are the result of the standard deviation (rms) of the conversion data with inputs shorted and biased to the mid-supply voltage and are representative of typical performance at TA = 25°C. A minimum of 1,000 or 10 seconds of consecutive conversions (whichever occurs first) are used to measure RMS noise (en). Because of the statistical nature of noise, repeated noise measurements can yield higher or lower noise results.
Equation 12 converts RMS noise to dynamic range (dB) and Equation 13 converts RMS noise to effective resolution (bits).
where:
When evaluating ADC noise performance, consider the effect of external buffer and amplifier noise to the total noise performance. The noise performance of the ADC can be evaluated in isolation by selecting the input short test connection of the input multiplexer.
OSR | DATA RATE (kSPS) |
–0.1-dB FREQUENCY (kHz) |
NOISE (en) (µVRMS) |
DYNAMIC RANGE (dB) |
EFFECTIVE RESOLUTION (Bits) |
---|---|---|---|---|---|
HIGH-SPEED MODE (fCLK = 25.6 MHz) | |||||
32 | 400 | 165.000 | 10.6 | 108.7 | 19.5 |
64 | 200 | 82.500 | 7.47 | 111.8 | 20.1 |
128 | 100 | 41.250 | 5.20 | 114.9 | 20.6 |
256 | 50 | 20.625 | 3.66 | 118.0 | 21.1 |
512 | 25 | 10.312 | 2.58 | 121.0 | 21.6 |
1024 | 12.5 | 5.156 | 1.83 | 124.0 | 22.1 |
2048 | 6.25 | 2.578 | 1.29 | 127.0 | 22.6 |
4096 | 3.125 | 1.289 | 0.92 | 130.0 | 23.1 |
LOW-SPEED MODE (fCLK = 3.2 MHz) | |||||
32 | 50 | 20.625 | 10.6 | 108.7 | 19.5 |
64 | 25 | 10.312 | 7.47 | 111.8 | 20.1 |
128 | 12.5 | 5.156 | 5.20 | 114.9 | 20.6 |
256 | 6.25 | 2.578 | 3.66 | 118.0 | 21.1 |
512 | 3.125 | 1.289 | 2.58 | 121.0 | 21.6 |
1024 | 1.5625 | 0.645 | 1.83 | 124.0 | 22.1 |
2048 | 0.78125 | 0.322 | 1.29 | 127.0 | 22.6 |
4096 | 0.390625 | 0.161 | 0.92 | 130.0 | 23.1 |
OSR | DATA RATE (kSPS) |
–3-dB FREQUENCY (kHz) |
NOISE (en) (µVRMS) |
DYNAMIC RANGE (dB) |
EFFECTIVE RESOLUTION (Bits) |
---|---|---|---|---|---|
HIGH-SPEED MODE (fCLK = 25.6 MHz) | |||||
12 | 1066.666 | 242.666 | 76.3 | 91.6 | 16.7 |
16 | 800 | 182.000 | 27.3 | 100.5 | 18.2 |
24 | 533.333 | 121.333 | 10.4 | 108.9 | 19.6 |
32 | 400 | 91.000 | 7.96 | 111.2 | 20.0 |
64 | 200 | 45.500 | 5.57 | 114.3 | 20.5 |
128 | 100 | 22.750 | 3.90 | 117.4 | 21.0 |
256 | 50 | 11.375 | 2.80 | 120.3 | 21.5 |
512 | 25 | 5.687 | 1.98 | 123.3 | 22.0 |
1024 | 12.5 | 2.844 | 1.40 | 126.3 | 22.5 |
2048 | 6.25 | 1.422 | 0.99 | 129.3 | 23.0 |
4096 | 3.125 | 0.711 | 0.70 | 132.3 | 23.5 |
LOW-SPEED MODE (fCLK = 3.2 MHz) | |||||
12 | 133.333 | 30.333 | 76.3 | 91.6 | 16.7 |
16 | 100 | 22.750 | 27.3 | 100.5 | 18.2 |
24 | 66.666 | 15.166 | 10.4 | 108.9 | 19.6 |
32 | 50 | 11.375 | 7.96 | 111.2 | 20.0 |
64 | 25 | 5.687 | 5.57 | 114.3 | 20.5 |
128 | 12.5 | 2.844 | 3.90 | 117.4 | 21.0 |
256 | 6.25 | 1.422 | 2.80 | 120.3 | 21.5 |
512 | 3.125 | 0.711 | 1.98 | 123.3 | 22.0 |
1024 | 1.5625 | 0.355 | 1.40 | 126.3 | 22.5 |
2048 | 0.78125 | 0.177 | 0.99 | 129.3 | 23.0 |
4096 | 0.390625 | 0.089 | 0.70 | 132.3 | 23.5 |
SINC4 OSR | SINC1 OSR | DATA RATE (kSPS) |
–3-dB FREQUENCY (kHz) |
NOISE (en) (µVRMS) |
DYNAMIC RANGE (dB) |
EFFECTIVE RESOLUTION (Bits) |
---|---|---|---|---|---|---|
HIGH-SPEED MODE (fCLK = 25.6 MHz) | ||||||
32 | 2 | 200 | 68.35 | 5.63 | 114.2 | 20.5 |
32 | 4 | 100 | 40.97 | 3.98 | 117.2 | 21.0 |
32 | 10 | 40 | 17.47 | 2.81 | 120.3 | 21.5 |
32 | 20 | 20 | 8.814 | 1.99 | 123.3 | 22.0 |
32 | 40 | 10 | 4.420 | 1.41 | 126.3 | 22.5 |
32 | 100 | 4 | 1.770 | 0.99 | 129.3 | 23.0 |
32 | 200 | 2 | 0.885 | 0.70 | 132.3 | 23.5 |
32 | 400 | 1 | 0.442 | 0.52 | 134.9 | 23.9 |
32 | 1000 | 0.4 | 0.177 | 0.39 | 137.4 | 24.3 |
LOW-SPEED MODE (fCLK = 3.2 MHz) | ||||||
32 | 2 | 25 | 8.544 | 5.63 | 114.2 | 20.5 |
32 | 4 | 12.5 | 5.121 | 3.98 | 117.2 | 21.0 |
32 | 10 | 5 | 2.184 | 2.81 | 120.3 | 21.5 |
32 | 20 | 2.5 | 1.102 | 1.99 | 123.3 | 22.0 |
32 | 40 | 1.25 | 0.552 | 1.41 | 126.3 | 22.5 |
32 | 100 | 0.5 | 0.221 | 0.99 | 129.3 | 23.0 |
32 | 200 | 0.25 | 0.111 | 0.70 | 132.3 | 23.5 |
32 | 400 | 0.125 | 0.055 | 0.52 | 134.9 | 23.9 |
32 | 1000 | 0.05 | 0.022 | 0.39 | 137.4 | 24.3 |
OSR | DATA RATE (SPS) |
–3-dB FREQUENCY (Hz) |
NOISE (en) (µVRMS) (1) |
DYNAMIC RANGE (dB) |
EFFECTIVE RESOLUTION (Bits) |
---|---|---|---|---|---|
HIGH-SPEED MODE (fCLK = 25.6 MHz) | |||||
26667 | 480 | 126 | 0.29 | 140.0 | 24.7 |
32000 | 400 | 105 | 0.27 | 140.6 | 24.8 |
LOW-SPEED MODE (fCLK = 3.2 MHz) | |||||
26667 | 60 | 16 | 0.29 | 140.0 | 24.7 |
32000 | 50 | 13 | 0.27 | 140.6 | 24.8 |
SINC3 OSR | SINC1 OSR | DATA RATE (SPS) |
–3-dB FREQUENCY (Hz) |
NOISE (en) (µVRMS) (1) |
DYNAMIC RANGE (dB) |
EFFECTIVE RESOLUTION (Bits) |
---|---|---|---|---|---|---|
HIGH-SPEED MODE (fCLK = 25.6 MHz) | ||||||
32000 | 3 | 133.3 | 54 | 0.19 | 143.7 | 25.3 |
32000 | 5 | 80 | 34 | 0.15 | 145.7 | 25.7 |
LOW-SPEED MODE (fCLK = 3.2 MHz) | ||||||
32000 | 3 | 16.6 | 6.7 | 0.19 | 143.7 | 25.3 |
32000 | 5 | 10 | 4.3 | 0.15 | 145.7 | 25.7 |