Datasheet
TAS5508C
SLES257–SEPTEMBER 2010
www.ti.com
Contents
1 Introduction PWM ............................................................................................................... 9
1.1 Features ...................................................................................................................... 9
1.2 Overview .................................................................................................................... 10
1.3 TAS5508C System Diagrams ............................................................................................ 12
2 Description ....................................................................................................................... 15
2.1 Physical Characteristics .................................................................................................. 15
2.1.1 Terminal Assignments ......................................................................................... 15
2.1.2 Ordering Information ........................................................................................... 15
2.1.3 PIN Descriptions ................................................................................................ 16
2.2 TAS5508C Functional Description ...................................................................................... 17
2.2.1 Power Supply ................................................................................................... 18
2.2.2 Clock, PLL, and Serial Data Interface ....................................................................... 18
2.2.2.1 Serial Audio Interface .............................................................................. 18
2.2.3 I
2
C Serial-Control Interface ................................................................................... 19
2.2.4 Device Control .................................................................................................. 19
2.2.5 Digital Audio Processor (DAP) ................................................................................ 19
2.2.5.1 TAS5508C Audio-Processing Configurations .................................................. 19
2.2.5.2 TAS5508C Audio Signal-Processing Functions ................................................ 20
2.3 TAS5508C DAP Architecture ............................................................................................ 21
2.3.1 TAS5508C DAP Architecture Diagrams ..................................................................... 21
2.3.2 I
2
C Coefficient Number Formats ............................................................................. 24
2.3.2.1 28-Bit 5.23 Number Format ....................................................................... 24
2.3.2.2 48-Bit 25.23 Number Format ..................................................................... 26
2.3.2.3 TAS5508C Audio Processing .................................................................... 27
2.4 Input Crossbar Mixer ...................................................................................................... 28
2.5 Biquad Filters .............................................................................................................. 28
2.6 Bass and Treble Controls ................................................................................................ 29
2.7 Volume, Automute, and Mute ............................................................................................ 30
2.8 Automute and Mute ....................................................................................................... 30
2.9 Loudness Compensation ................................................................................................. 31
2.9.1 Loudness Example ............................................................................................. 32
2.10 Dynamic Range Control (DRC) .......................................................................................... 33
2.10.1 DRC Implementation ........................................................................................... 36
2.10.2 Compression/Expansion Coefficient Computation Engine Parameters ................................. 36
2.10.2.1 Threshold Parameter Computation .............................................................. 37
2.10.2.2 Offset Parameter Computation ................................................................... 37
2.10.2.3 Slope Parameter Computation ................................................................... 38
2.11 Output Mixer ............................................................................................................... 38
2.12 PWM ........................................................................................................................ 39
2.12.1 DC Blocking (High-Pass Enable/Disable) ................................................................... 40
2.12.2 De-Emphasis Filter ............................................................................................. 40
2.12.3 Power-Supply Volume Control (PSVC) ...................................................................... 40
2.12.4 AM Interference Avoidance ................................................................................... 41
3 TAS5508C Controls and Status ........................................................................................... 43
3.1 I
2
C Status Registers ....................................................................................................... 43
3.1.1 General Status Register (0x01) ............................................................................... 43
2 Contents Copyright © 2010, Texas Instruments Incorporated