Other Parts Discussed in Thread: ADS1291, ADS1292
请问这个寄存器配置和那些因素有关系,如何选取,目前采样率是500sps,实测配置为fDOM/4效果更好
您好
This register controls the selection of the positive and negative signals from each channel for right leg drive derivation. See the Right Leg Drive (RLD DC Bias Circuit) subsection of the ECG-Specific Functions section for details.
根据datasheet中的这部分说明,请参考以下部分的选择:
8.3.10.2.4 Right Leg Drive (RLD DC Bias Circuit) The right leg drive (RLD) circuitry is used as a means to counter the common-mode interference in a ECG system as a result of power lines and other sources, including fluorescent lights. The RLD circuit senses the common-mode of a selected set of electrodes and creates a negative feedback loop by driving the body with an inverted common-mode signal. The negative feedback loop restricts the common-mode movement to a narrow range, depending on the loop gain. Stabilizing the entire loop is specific to the individual user system based on the various poles in the loop. The ADS1291, ADS1292, and ADS1292R integrates the muxes to select the channel and an operational amplifier. All the amplifier terminals are available at the pins, allowing the user to choose the components for the feedback loop. The circuit shown in Figure 40 shows the overall functional connectivity for the RLD bias circuit. The reference voltage for the right leg drive can be chosen to be internally generated (AVDD + AVSS) / 2 or it can be provided externally with a resistive divider. The selection of an internal versus external reference voltage for the RLD loop is defined by writing the appropriate value to the RLDREF_INT bit in the RESP2 register.
详情请参考datasheet第38页