Table Of Contents - Cirrus Logic WM8940 Manual

DESCRIPTION ................................................................................................................ 1
FEATURES ..................................................................................................................... 1
APPLICATIONS ............................................................................................................. 1
BLOCK DIAGRAM ......................................................................................................... 2
TABLE OF CONTENTS .................................................................................................. 3
PIN CONFIGURATION ................................................................................................... 6
ORDERING INFORMATION ........................................................................................... 6
PIN DESCRIPTION ......................................................................................................... 7
ABSOLUTE MAXIMUM RATINGS ................................................................................. 8
RECOMMENDED OPERATING CONDITIONS .............................................................. 8
ELECTRICAL CHARACTERISTICS .............................................................................. 9
TERMINOLOGY ....................................................................................................................... 11
AUDIO PATHS OVERVIEW ......................................................................................... 12
POWER CONSUMPTION ............................................................................................. 13
SIGNAL TIMING REQUIREMENTS ............................................................................. 14
SYSTEM CLOCK TIMING ........................................................................................................ 14
AUDIO INTERFACE TIMING - MASTER MODE .................................................................... 15
AUDIO INTERFACE TIMING - SLAVE MODE ........................................................................ 16
CONTROL INTERFACE TIMING - 3-WIRE MODE ................................................................. 17
CONTROL INTERFACE TIMING - 2-WIRE MODE ................................................................. 18
DEVICE DESCRIPTION ............................................................................................... 19
INTRODUCTION ...................................................................................................................... 19
FEATURES .................................................................................................................................................................................... 19
MICROPHONE INPUTS ................................................................................................................................................................ 19
PGA AND ALC OPERATION ........................................................................................................................................................ 19
AUX INPUT .................................................................................................................................................................................... 19
ADC ............................................................................................................................................................................................... 19
HI-FI DAC ...................................................................................................................................................................................... 19
DIGITAL FILTERING ..................................................................................................................................................................... 19
OUTPUT MIXING AND VOLUME ADJUST .................................................................................................................................. 19
AUDIO INTERFACES .................................................................................................................................................................... 19
CONTROL INTERFACES ............................................................................................................................................................. 20
CLOCKING SCHEMES ................................................................................................................................................................. 20
POWER CONTROL ....................................................................................................................................................................... 20
INPUT SIGNAL PATH .............................................................................................................. 20
MICROPHONE INPUTS ................................................................................................................................................................ 20
INPUT PGA VOLUME CONTROL ................................................................................................................................................. 22
AUXILIARY INPUT ........................................................................................................................................................................ 22
INPUT BOOST............................................................................................................................................................................... 23
MICROPHONE BIASING CIRCUIT ............................................................................................................................................... 24
ANALOGUE TO DIGITAL CONVERTER (ADC) ...................................................................... 25
ADC DIGITAL FILTERS ................................................................................................................................................................ 25
SELECTABLE HIGH PASS FILTER .............................................................................................................................................. 26
PROGRAMMABLE NOTCH FILTERS .......................................................................................................................................... 27
DIGITAL ADC VOLUME CONTROL ............................................................................................................................................. 29
INPUT LIMITER / AUTOMATIC LEVEL CONTROL (ALC) ...................................................... 29
NORMAL MODE ............................................................................................................................................................................ 32
LIMITER MODE ............................................................................................................................................................................. 32
ATTACK AND DECAY TIMES ....................................................................................................................................................... 33
NORMAL MODE ............................................................................................................................................................................ 33
LIMITER MODE ............................................................................................................................................................................. 34
Rev 4.4

TABLE OF CONTENTS

WM8940
3