SLASEC8B February 2017 – January 2019 PGA460-Q1
The rectifier, peak extractor, and low-pass filter DSP blocks demodulate the echo signal while outputting a base-band representation to be compared against the programmed thresholds. These blocks are defined as:
On power up the PGA460-Q1 device calculates the values of the filter coefficients and places them in the LPF_A2_xSB and LPF_B1_xSB registers, respectively. The user can overwrite the values in these registers and reconfigure the filter. In this case, the PGA460-Q1 device does not take any action. However, if the LPF_CO bit is changed, the coefficient calculation sequence must be rerun and the device repopulates these registers.