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1What: /sys/bus/iio/devices/iio:deviceX/boost_current_gain2KernelVersion: 6.43Contact: linux-iio@vger.kernel.org4Description:5 This attribute is used to set the gain of the biasing current6 circuit of the Delta-Sigma modulator. The different BOOST7 settings are applied to the entire modulator circuit, including8 the voltage reference buffers.9 10What: /sys/bus/iio/devices/iio:deviceX/boost_current_gain_available11KernelVersion: 6.412Contact: linux-iio@vger.kernel.org13Description:14 Reading returns a list with the possible gain values for15 the current biasing circuit of the Delta-Sigma modulator.16 17What: /sys/bus/iio/devices/iio:deviceX/auto_zeroing_mux_enable18KernelVersion: 6.419Contact: linux-iio@vger.kernel.org20Description:21 This attribute is used to enable the analog input multiplexer22 auto-zeroing algorithm (the input multiplexer and the ADC23 include an offset cancellation algorithm that cancels the offset24 contribution of the ADC). When the offset cancellation algorithm25 is enabled, ADC takes two conversions, one with the differential26 input as VIN+/VIN-, one with VIN+/VIN- inverted. In this case the27 conversion time is multiplied by two compared to the default28 case where the algorithm is disabled. This technique allows the29 cancellation of the ADC offset error and the achievement of30 ultra-low offset without any digital calibration. The resulting31 offset is the residue of the difference between the two32 conversions, which is on the order of magnitude of the noise33 floor. This offset is effectively canceled at every conversion,34 so the residual offset error temperature drift is extremely low.35 Write '1' to enable it, write '0' to disable it.36 37What: /sys/bus/iio/devices/iio:deviceX/auto_zeroing_ref_enable38KernelVersion: 6.439Contact: linux-iio@vger.kernel.org40Description:41 This attribute is used to enable the chopping algorithm for the42 internal voltage reference buffer. This setting has no effect43 when external voltage reference is selected.44 Internal voltage reference buffer injects a certain quantity of45 1/f noise into the system that can be modulated with the46 incoming input signals and can limit the SNR performance at47 higher Oversampling Ratio values (over 256). To overcome this48 limitation, the buffer includes an auto-zeroing algorithm that49 greatly reduces (cancels out) the 1/f noise and cancels the50 offset value of the reference buffer. As a result, the SNR of51 the system is not affected by this 1/f noise component of the52 reference buffer, even at maximum oversampling ratio values.53 Write '1' to enable it, write '0' to disable it.54