ZHCSHT9C August 2021 – June 2024 ADC12DJ4000RF
PRODUCTION DATA
When the ADC is operating in dual-input single channel mode (based on the JMODE setting and SINGLE_INPUT setting) then the PFIR filter can be set in time varying filter mode. This mode enables a time varying filter with two coefficient sets that are alternated between on a per sample basis. Each coefficient set consists of 9 coefficients that can be independently set. The center tap of the filter has a resolution of 18 bits and the LSB has a weight of 2-16. The non-center taps have a resolution of 12-bits with programmable LSB weight of 2-10, 2-11, 2-12, 2-13, 2-14, 2-15 or 2-16. All non-center taps have the same LSB weight. The block diagram for time varying filter mode is shown in Figure 7-6 and an alternate block diagram is given in Figure 7-7 which shows the equivalent filter in an I/Q correction-type topology.