1What: /sys/bus/iio/devices/iio:deviceX/boost_current_gain 2KernelVersion: 6.4 3Contact: linux-iio@vger.kernel.org 4Description: 5 This attribute is used to set the gain of the biasing current 6 circuit of the Delta-Sigma modulator. The different BOOST 7 settings are applied to the entire modulator circuit, including 8 the voltage reference buffers. 9 10What: /sys/bus/iio/devices/iio:deviceX/boost_current_gain_available 11KernelVersion: 6.4 12Contact: linux-iio@vger.kernel.org 13Description: 14 Reading returns a list with the possible gain values for 15 the current biasing circuit of the Delta-Sigma modulator. 16 17What: /sys/bus/iio/devices/iio:deviceX/auto_zeroing_mux_enable 18KernelVersion: 6.4 19Contact: linux-iio@vger.kernel.org 20Description: 21 This attribute is used to enable the analog input multiplexer 22 auto-zeroing algorithm (the input multiplexer and the ADC 23 include an offset cancellation algorithm that cancels the offset 24 contribution of the ADC). When the offset cancellation algorithm 25 is enabled, ADC takes two conversions, one with the differential 26 input as VIN+/VIN-, one with VIN+/VIN- inverted. In this case the 27 conversion time is multiplied by two compared to the default 28 case where the algorithm is disabled. This technique allows the 29 cancellation of the ADC offset error and the achievement of 30 ultra-low offset without any digital calibration. The resulting 31 offset is the residue of the difference between the two 32 conversions, which is on the order of magnitude of the noise 33 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_enable 38KernelVersion: 6.4 39Contact: linux-iio@vger.kernel.org 40Description: 41 This attribute is used to enable the chopping algorithm for the 42 internal voltage reference buffer. This setting has no effect 43 when external voltage reference is selected. 44 Internal voltage reference buffer injects a certain quantity of 45 1/f noise into the system that can be modulated with the 46 incoming input signals and can limit the SNR performance at 47 higher Oversampling Ratio values (over 256). To overcome this 48 limitation, the buffer includes an auto-zeroing algorithm that 49 greatly reduces (cancels out) the 1/f noise and cancels the 50 offset value of the reference buffer. As a result, the SNR of 51 the system is not affected by this 1/f noise component of the 52 reference buffer, even at maximum oversampling ratio values. 53 Write '1' to enable it, write '0' to disable it. 54