SLAU367P October 2012 – April 2020 MSP430FR5041 , MSP430FR5043 , MSP430FR50431 , MSP430FR5847 , MSP430FR58471 , MSP430FR5848 , MSP430FR5849 , MSP430FR5857 , MSP430FR5858 , MSP430FR5859 , MSP430FR5867 , MSP430FR58671 , MSP430FR5868 , MSP430FR5869 , MSP430FR5870 , MSP430FR5872 , MSP430FR58721 , MSP430FR5887 , MSP430FR5888 , MSP430FR5889 , MSP430FR58891 , MSP430FR5922 , MSP430FR59221 , MSP430FR5947 , MSP430FR59471 , MSP430FR5948 , MSP430FR5949 , MSP430FR5957 , MSP430FR5958 , MSP430FR5959 , MSP430FR5962 , MSP430FR5964 , MSP430FR5967 , MSP430FR5968 , MSP430FR5969 , MSP430FR5969-SP , MSP430FR59691 , MSP430FR5970 , MSP430FR5972 , MSP430FR59721 , MSP430FR5986 , MSP430FR5987 , MSP430FR5988 , MSP430FR5989 , MSP430FR5989-EP , MSP430FR59891 , MSP430FR5992 , MSP430FR5994 , MSP430FR59941 , MSP430FR6005 , MSP430FR6007 , MSP430FR6035 , MSP430FR6037 , MSP430FR60371 , MSP430FR6041 , MSP430FR6043 , MSP430FR60431 , MSP430FR6045 , MSP430FR6047 , MSP430FR60471 , MSP430FR6820 , MSP430FR6822 , MSP430FR68221 , MSP430FR6870 , MSP430FR6872 , MSP430FR68721 , MSP430FR6877 , MSP430FR6879 , MSP430FR68791 , MSP430FR6887 , MSP430FR6888 , MSP430FR6889 , MSP430FR68891 , MSP430FR6920 , MSP430FR6922 , MSP430FR69221 , MSP430FR6927 , MSP430FR69271 , MSP430FR6928 , MSP430FR6970 , MSP430FR6972 , MSP430FR69721 , MSP430FR6977 , MSP430FR6979 , MSP430FR69791 , MSP430FR6987 , MSP430FR6988 , MSP430FR6989 , MSP430FR69891
22.2.3.3 Digital Filter Output
Figure 22-7 shows the block diagram of the SDHS digital filter. The CIC7 is a 7th-order CIC filter with decimation of 10. The CIC1 is a 1st-order CIC filter with programmable decimation of 2, 4, 8, or 16. By cascading the two filters, OSR of 10, 20, 40, 80, or 160 is offered. The OSR ratio is configured by the SDHSCTL1.OSR bits. Each output of the CIC7 and CIC1 is truncated to 14 bits. The final output data is 16 bit, but the effective number of bits and data format are programmable through the SDHSCTL0.DALGN, SDHSCTL0.OBR, SDHSCTL0.SHIFT, and SDHSCTL0.DFMSEL bits.
Figure 22-7 Digital Filter Block Diagram The final frequency response of the SDHS digital filter is determined by SDHSCTL1.OSR bit. Figure 22-8 shows the frequency response of cascading CIC7 and CIC1 beyond fs (normalized) when SDHSCTL1.OSR = 20.
Figure 22-8 SDHS Filter Frequency Response, SDHSCTL1.OSR = 20 Figure 22-9 shows the frequency response of cascading CIC7 and CIC1 within fs (normalized) when SDHSCTL1.OSR = 20.
Figure 22-9 SDHS Filter Frequency Response Within fs, SDHSCTL1.OSR = 20 Figure 22-10 shows the frequency response of cascading CIC7 and CIC1 within fs (normalized) when SDHSCTL1.OSR = 40.
Figure 22-10 SDHS Filter Frequency Response within fs, SDHSCTL1.OSR = 40 Figure 22-11 shows the frequency response of cascading CIC7 and CIC1 within fs (normalized) when SDHSCTL1.OSR = 80.
Figure 22-11 SDHS Filter Frequency Response within fs, SDHSCTL1.OSR = 80 Figure 22-12 shows the frequency response of cascading CIC7 and CIC1 within fs (normalized) when SDHSCTL1.OSR = 160.
Figure 22-12 SDHS Filter Frequency Response within fs, SDHSCTL1.OSR = 160