CM108AH
A High Integrated USB Audio I/O Controller
TABLE OF CONTENTS
1 Description and Overview ..................................................................... 3
2 Features .......................................................................................... 3
3 Pin Descriptions ................................................................................. 5
3.1 Pin Assignment by Pin Number................................................................................. 5
3.2 Pin-Out Diagram.................................................................................................. 5
3.3 Pin Signal Descriptions .......................................................................................... 6
4 I²S Interface ..................................................................................... 8
5 Block Diagram ................................................................................... 9
6 Ordering Information.......................................................................... 10
7 Function Description .......................................................................... 11
7.1 USB Interface .................................................................................................... 11
7.1.1
Device Descriptor .............................................................................................. 11
7.1.2
Configuration Descriptor...................................................................................... 12
7.1.3
Content Format for EEPROM (93C46) ....................................................................... 13
7.1.4
USB Audio Topology Diagram................................................................................. 14
7.2 Jumper Pins and Mode Setting:............................................................................... 15
7.3 HID Feature ...................................................................................................... 16
7.3.1
What’s HID ...................................................................................................... 16
7.3.2
HID Descriptor.................................................................................................. 17
7.3.3
Windows Software Architecture for HID .................................................................... 18
7.4 Internal Registers ............................................................................................... 19
8 Electrical Characteristics..................................................................... 22
8.1 Absolute Maximum Rating ..................................................................................... 22
8.2 Operation Conditions........................................................................................... 22
8.3 Electrical Parameters .......................................................................................... 23
9 Audio Quality Graphs.......................................................................... 24
9.1 Line Out Freq Response @ 48KHz Sample Rate (10K Ohm Loading).................................... 24
9.2 Line Out THD+N @ 48KHz sample rate (10K Ohm Loading) .............................................. 24
9.3 Microphone Input Freq Response @ 48KHz Sample Rate ................................................. 25
9.4 Microphone Input THD+N @ 48KHz Sample Rate .......................................................... 25
Reference ............................................................................................ 26
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