SS
Best USB Audio I/O Controller for
Headset and Multi-Media Devices
CM108 High Integrated
USB Audio I/O Controller
DataSheet 1.5
C-MEDIA ELECTRONICS INC.
TEL: 886-2-8773-1100 FAX: 886-2-8773-2211
6F, 100, Sec. 4, Civil Boulevard, Taipei, Taiwan 106, R.O.C.
For detailed product information, please contact
TU
sales@cmedia.com.tw
UT
CM108
Integration Dual DAC, Earphone Driver, ADC,
Microphone Booster, PLL, Regulator, and USB Transceiver
Date: Nov/01/2004 Version: 1.5
- 1 -
NOTICES
THIS DOCUMENT IS PROVIDED "AS IS" WITH NO WARRANTIES WHAT SO EVER,
INCLUDING ANY WARRANTY OF MERCHANT ABILITY, NONINFRINGEMENT, FITNESS FOR
ANY PARTICULAR PURPOSE, OR ANY WARRANTY OTHERWISE ARISING OUT OF ANY
PROPOSAL, DOCUMENT OR SAMPLE.
ALL RIGHTS RESERVED. NO PART OF THIS DOCUMENT MAY BE REPRODUCED OR
TRANSMITTED IN ANY FORM OR BY ANY MEANS, ELECTRONIC OR MECHANICAL,
INCLUDING INFORMATION STORAGE AND RETRIEVAL SYSTEMS, WITHOUT
PERMISSION IN WRITING FROM C-MEDIA ELECTRONICS, INC.
U
COPYRIGHT
Copyright (c) 2003-2004 C-Media Electronics Inc.
All rights reserved. All content included on this document, such as text, graphics, logos, button
icons, images, audio clips, digital downloads, data compilations, and software, is either the
exclusive property of C-Media Electronics Inc., its affiliates (collectively, "C-Media"), its content
suppliers, or its licensors and protected by Republic of China and international copyright laws.
U
TRADEMARKS
C-Media, the C-Media Logo, Xear 3D, Xear 3D Logo, Speaker Shifter, Smart Jack, and Smart
Audio Jack are trademarks of C-Media Electronics Inc. in Republic of China and/or other
countries. All other brand and product names listed are trademarks or registered trademarks of
their respective holders and are hereby recognized as such.
*C-Media reserves the right to modify the specifications without further notice*
CM108
Integration Dual DAC, Earphone Driver, ADC,
Microphone Booster, PLL, Regulator, and USB Transceiver
Date: Nov/01/2004 Version: 1.5
- 2 -
TABLE OF CONTENTS
1. DESCRIPTION AND OVERVIEW
2. FEATURES
3. PIN DESCRIPTIONS
3.1
PIN ASSIGNMENT BY PIN NUMBER
3.2
PIN-OUT DIAGRAM
3.3
PIN SIGNAL DESCRIPTIONS
4. IS INTERFACE
5. BLOCK DIAGRAM
6. ORDERING INFORMATION
7. FUNCTION DESCRIPTIONS
7.1
USB INTERFACE
7.1.1
DEVICE DESCRIPTOR
7.1.2
CONFIGURATION DESCRIPTOR
7.1.3
CONTENT FORMAT FOR 94C46
7.1.4
USB AUDIO TOPOLOGY DIAGRAM
7.2
JUMPER PINS AND MODE SETTING
7.2.1
MODE PIN AND MSEL PIN
7.2.2
MODE PIN AND PWRSEL PIN
7.2.3
VSEL PIN
7.3
HID FEATURE
7.4
INTERNAL REGISTERS
CM108
Integration Dual DAC, Earphone Driver, ADC,
Microphone Booster, PLL, Regulator, and USB Transceiver
Date: Nov/01/2004 Version: 1.5
- 3 -
8. ELECTRICAL CHARACTERISTICS
8.1
ABSOLUTE MAXIMUM RATING
8.2
OPERATION CONDITIONS
8.3
ELECTRICAL PARAMETERS
8.4
AUDIO PERFORMANCE
9. FREQUENCY RESPONSE GRAPHS
9.1
DIGITAL PLAYBACK FOR LINE OUTPUT FREQUENCY (10K OHM LOADING)
9.1.1
FREQUENCY RESPONSE 48KS/SEC
9.1.2
FREQUENCY RESPONSE 44.1KS/SEC
9.2
DIGITAL PLAYBACK FOR LINE OUTPUT FREQUENCY (32 OHM LOADING)
9.2.1
FREQUENCY RESPONSE 48KS/SEC
9.2.2
FREQUENCY RESPONSE 44.1KS/SEC
9.3
DIGITAL RECORDING FOR LINE OUTPUT FREQUENCY
9.3.1
FREQUENCY RESPONSE 48KS/SEC
9.3.2
FREQUENCY RESPONSE 44.1KS/SEC
10. REFERENCE APPLICATION CIRCUIT
CM108
Integration Dual DAC, Earphone Driver, ADC,
Microphone Booster, PLL, Regulator, and USB Transceiver
Date: Nov/01/2004 Version: 1.5
- 4 -
1.
DESCRIPTION AND OVERVIEW
CM108 is a highly integrated single chip USB audio solution. All essential analog modules
are embedded in CM108, including dual DAC and earphone driver, ADC, microphone booster,
PLL, regulator, and USB transceiver. It is very suitable for USB headset, USB earphone or
USB audio interface box application. Many features are programmable with jumper pins or
external EEPROM. In addition, audio adjustment can be easily controlled via specific HID
compliant volume control pins. For value added application, external codec or audio DSP can
be connected to CM108 via I
2
S pin for further processing. 4 GPIO pins can be accessed with
customer application software for additional value added application.
2. FEATURES
Compliant with USB 2.0 Full Speed Operation
Compliant with USB Audio Device Class Specification v1.0
Supports USB Suspend / Resume Mode and Remote Wakeup with Volume Control
Pins
Single 12MHz Crystal Input with On-chip PLL and Embedded USB Transceiver
Jumper Pin for Speaker Mode (Playback Only) or Headset Mode (Playback +
Recording)
For Headset Mode, USB Audio Function Topology has 2 Input Terminals, 2 Output
Terminals, 1 Mixer Unit, 1 Selector Unit, and 3 Feature Units
Jumper Pin for Mixer Unit Enable / Disable under Headset Mode
For Speaker Mode, USB Audio Function Topology has 1 Input Terminal, 1 Output
Terminal, and 1 Feature Unit
Support One Control Endpoint, One Isochronous Out Endpoint, One Isochronous In
Endpoint, and One Interrupt In Endpoint
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