SBAA378B November   2019  – December 2023 PCM3140-Q1 , PCM5140-Q1 , PCM6140-Q1 , TLV320ADC3140 , TLV320ADC5140 , TLV320ADC6140

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Introduction
  5. 2 Infinite Impulse Response Filters
    1. 2.1 Digital Biquad Filter
  6. 3  TLV320ADCx140/PCMx140-Q1 Digital Biquad Filters
    1. 3.1 Filter Design Using PurePath™ Console
      1. 3.1.1 Example Generating Programmable Biquad Coefficients Using PurePath Console
    2. 3.2 How to Generate N0, N1, N2, D1, and D2 Coefficients with a Digital Filter Design Package
    3. 3.3 Avoid Overflow Conditions
    4. 3.4 Digital Biquad FiIter Allocation to Output Channel
    5. 3.5 Programmable Coefficient Registers for Digital Biquad Filters 1–6
    6. 3.6 Programmable Coefficient Registers for Digital Biquad Filters 7–12
  7. 4 How to Program the Digital Biquad Filters on TLV320ADCx140/PCMx140-Q1
  8. 5 Typical Audio Applications for Biquad Filtering
    1. 5.1 Parametric Equalizers
  9. 6 Crossover Networks
  10. 7 Voice Boost
  11. 8 Bass Boost
  12. 9 Removing 50 Hz–60 Hz Hum With Notch Filters
  13. 10Revision History
  14. 11Digital Filter Design Techniques
    1. 11.1 Analog Filters

4 How to Program the Digital Biquad Filters on TLV320ADCx140/PCMx140-Q1

Coefficients of Digital Biquad Filters can be implemented by running a command script to send an I2C command to the EVM. The following script segment shows how to program the coefficients for a set of filters for 5-dB boost at 500 Hz with bandwidth of 400 Hz, cut –5 dB at 2 kHz with 3-kHz bandwidth, and a Notch filter at 60 Hz with 50-Hz bandwidth for channel 1.


# Select Page 2
w 98 00 02
# Write Coefficient N0, N1, N2, D1, D2 for Biquad Filter 1
w 98 08 7f ff ff ff 85 dc e2 7d 74 cc 68 8f 7c 77 a7 18 86 87 f4 ee 
# Write Coefficient N0, N1, N2, D1, D2 for Biquad Filter 5
w 98 58 71 80 7d b6 a4 5b f4 41 4c 3e c3 29 5b a4 0b bf c2 40 bf 20
# Select Page 3
w 98 00 03
# Write Coefficient N0, N1, N2, D1, D2 for Biquad Filter 9
w 98 30 7f 95 1d c9 80 6b e4 18 7f 95 1d c9 7f 94 1b e8 80 d5 c4 6d