CS5396-KS Cirrus Logic Inc, CS5396-KS Datasheet - Page 38

• Manufacturer Part Number: CS5396-KS
• Description: ADC Dual Delta-Sigma 96KSPS 24-Bit Serial 28-Pin SOIC
• Manufacturer: Cirrus Logic Inc

Specifications of CS5396-KS

• Package: 28SOIC
• Resolution: 24 Bit
• Sampling Rate: 96 KSPS
• Architecture: Delta-Sigma
• Number Of Analog Inputs: 2
• Digital Interface Type: Serial (SPI)
• Input Type: Voltage
• Sample And Hold: Yes
• Polarity Of Input Voltage: Bipolar

APPENDIX C: PSYCHOACOUSTIC FILTER
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The psychoacoustic filter in the CS5396 is based on the paper: "Robert A. Wannamaker, Psychoacous-
tically Optimal Noise Shaping, Journal of the Audio Engineering Society, Vol 40, No 7/8, 1992 July/Au-
gust." The default coefficients in the CS5396 are the FIR 9-tap filter coefficients described in Table 3 of
the paper. Since the effective noise shaping function is (1-H), the CS5396 registers save the (1-H) func-
tion coefficients. Therefore, the negative of each filter coefficient is stored in the registers. Each coefficient
is represented as a binary 2’s complement number where the 4 MSB’s represent the whole number of the
coefficient and the 4 LSB’s represent the fractional portion truncated to 4 binary bits.
Default Coefficients as listed in "Robert A. Wannamaker, Psychoacoustically Optimal Noise Shaping”
a1 = 2.412
a2 = -3.370
a3 = 3.937
a4 = -4.174
a5 = 3.353
a6 = -2.205
a7 = 1.281
a8 = -0.569
a9 = 0.0847
Coefficient conversion example 1:
a1 = 2.412
a1 = (0010.0110) binary repesentation with the fractional portion truncated to 4 bits.
-a1 = -(0010.0110) binary representation
-a1 = 1101.1010 in two’s complement
this value is stored in register 10h.
Coefficient conversion example 2:
a2 = -3.370
-a2 = 3.370
-a2 = 0011.0101
this value is stored in register 11h.
-a2 = 0011.0101 in 2's complement
binary repesentation with the fractional portion truncated to 4 bits.
CS5396 CS5397
DS229PP2xC