CM6327A

USB Single-Chip Audio Solution for Mono Microphone

DESCRIPTION FEATURES
The CM6327A is C-Media’s new Audio SOC IC  USB specification 2.0 full speed-compliant and
designed for advanced VoIP applications. It boasts USB IF-certified
a high-performance mono ADC, as well as I2C  USB audio device specification 1.0- and USB HID
interface, that allows for communication with specification 1.1-compliant
various microprocessors and DSPs. The CM6327A  Supports control/interrupt/isochroous data
offers low-noise, high-quality speech input, transfers
important when it comes to recording or  USB suspend/resume and remote wake-up
broadcasting conference calls or public speeches. support
 Embedded USB transceiver and power-on reset
Also, the CM6327A integrates all essential analog
circuit
modules, including 1-ch ADC, PLL, regulator and
 Single 12MHz crystal input with on-chip PLL
USB transceiver modules, along with an EEPROM
 Supports series number string for operation
that allows you to customize the product string,
system detection
PID and VID. Sampling rates of 8/11.025/16/22.05/
 Serial EEPROM programming interface supports
32/44.1 and 48 KHz, high-quality 16-bit resolutions
customized VID/PID/product and manufacture
and user-friendly general purpose inputs and
strings
outputs for customized functions are supported. In
 EEPROM interface supports 24C02 data format
addition, many features can be programmed using
an external EEPROM and MCU, which are easily
controlled via the HID software interface.

BLOCK DIAGRAM

CM6327A
GPIO/LED

PC USB Interface controller & 16-bit PGA

USB host interface signal processing 48KHz
ADC

Regulator ROM Register

Internal PLL I2C

PLL

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CM6327A
USB Single-Chip Audio Solution for Mono Microphone

TABLE OF CONTENTS

1 Description and Overview ................................................................................................ 4

2 Features ..................................................................................................................... 4
3 Pin Descriptions ............................................................................................................ 6
3.1 Pin Assignment by Pin Number ................................................................................. 6
3.2 Pin-Out Diagram .................................................................................................. 6
3.3 Pin Signal Descriptions .......................................................................................... 7
4 Block Diagram .............................................................................................................. 9
5 Ordering Information ..................................................................................................... 10
6 USB Audio Topology and Descriptions .................................................................................. 11
6.1 USB Audio Topology ............................................................................................. 11
6.2 Device Descriptors .............................................................................................. 11
6.3 Configuration Descriptors...................................................................................... 12
6.4 Standard HID Interface Descriptors .......................................................................... 13
7 Function Block Descriptions: ............................................................................................ 14
7.1 I2C Interface: .................................................................................................... 14
7.1.1 Master Mode: .......................................................................................... 14
7.1.2 Slave Mode: ............................................................................................ 15
7.1.3 EEPROM Data Format ................................................................................. 19
8 Electrical Characteristics: ............................................................................................... 21
8.1 Absolute Maximum Rating ............................................................................................... 21
8.2 Operation Conditions ..................................................................................................... 21
8.3 Electrical Parameters .................................................................................................... 22
9 Analog Performance ...................................................................................................... 23
9.1 ADC Frequency Response ...................................................................................... 23
9.2 ADC THD + N ..................................................................................................... 23
Reference ......................................................................................................................... 24

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USB Single-Chip Audio Solution for Mono Microphone

Release Notes

Revision Date Description

Updated the EEPROM data format

Address 0x09: Reserved

1.8 2010/4/26
Address 0x12 (Bit2): Reserved (0: Default)

Address 0x13: Reserved

1.9 2012/9/27 Revised format

Updated the EEPROM Data Format

Address 0x02(Bit3):Reserved
2.0 2012/10/1
Address 0x03(Bit7):Reserved
Address 0x0a:Reserved

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CM6327A
USB Single-Chip Audio Solution for Mono Microphone

1 Description and Overview

This is a highly integrated single-chip USB audio solution that is built for a wide range of USB audio
controller and applications. Based on our experiences designing and manufacturing PC USB Audio
peripherals, as well as recommendations from vendors, C-Media has designed this single-chip solution to
make it easier for vendors to integrate their products, and increase their revenues.

The CM6327A is C-Media’s new Audio SOC IC designed for advanced VoIP applications. It boasts a
high-performance mono ADC, as well as I2C interface, that allows for communication with various
microprocessors and DSPs. The CM6327A offers low-noise, high-quality speech input, important when it
comes to recording or broadcasting conference calls or public speeches.

The CM6327A integrates all essential analog modules, including 1-ch ADC, PLL, regulator and USB
transceiver modules, along with an EEPROM that allows you to customize the product string, PID and VID.
Sampling rates of 8/11.025/16/22.05/ 32/44.1 and 48 KHz, high-quality 16-bit resolutions and user-friendly
general purpose inputs and outputs for customized functions are supported. Many features can be
programmed using an external EEPROM and MCU, which are easily controlled via the HID software interface.

2 Features
 USB spec. 2.0 full speed-compatible and USB IF-certified
 USB audio device class 1.0- and USB HID specification 1.1-compliant
 Supports control/interrupt/isochroous data transfers
 USB suspend/resume and remote wake-up support
 Embedded USB transceiver and power-on reset circuit
 Single 12MHz crystal input with on-chip PLL
 Supports series number string for operation system detection
 Serial EEPROM programming interface supports customized VID/PID/product and manufacture strings
for device name changes and configurations
 EEPROM interface support 24C02 data format
 Mono ADC input:
ADC sampling rate of 8K/11.025K/16K/22.05K/32K/44.1K/48KHz, and 16-bit resolution
Dynamic range: 96db, THD+N: -89~96db
Digital linear microphone gain control function (-16db~45db)
1.0Vrms input swing biased at 2.25V
 Supports Microsoft HID functions
 Supports I2C (master/slave) control interface for external controller used

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USB Single-Chip Audio Solution for Mono Microphone

 I2C MCU read/write support 16 bytes data transfer bandwidth

 I2C interface support extra interrupt pin INT
 MCU/EEPROM/GPIO control via HID/vender command interface
 USB audio topology has 1 input terminal, 1 output terminal, 1 selector unit and 1 feature unit
 Supports 2 LED indicator pins:
1. On/Off/Operation
2. Recording mute
 Supports 8 GPIO and 2 GPI pins
 Isochronous transfer uses adaptive mode with Internal PLL for synchronization
 Embedded power-on-reset block
 Single 5V power supply with embedded 5V to 3.3V regulator
 Industry standard LQFP-48 pin package
 Compatible with Win2000/WinXP/Vista/Win7/MAC/OSX/Linux/Wii/XBOX360/PS2/PS3
 Supports hardware SDK tool for third-party software development

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CM6327A
USB Single-Chip Audio Solution for Mono Microphone

3 Pin Descriptions
3.1 Pin Assignment by Pin Number

Pin Signal Name Pin Signal Name Pin Signal Name Pin Signal Name

1 PDSW 13 N.C. 25 AVSS 37 AVDD

2 N.C. 14 HID_EN 26 MIC_IN 38 REGV_4V5

3 TEST 15 N.C. 27 N.C. 39 N.C.

4 GPIO_1 16 N.C. 28 VREF 40 GPI_1

5 GPIO_2 17 I2C_SCLK 29 VBIAS 41 GPI_2

6 GPIO_3 18 I2C_SDAT 30 N.C. 42 GPIO_5

7 GPIO_4 19 I2C_INT 31 AVDD 43 GPIO_6

8 LED_1 20 USB_DP 32 AVDD 44 GPIO_7

9 LED_3 21 USB_DM 33 AVSS 45 GPIO_8

10 XTAL_I 22 DVSS 34 AVSS 46 MUTE_REC

11 XTAL_O 23 REGV_3V3 35 N.C. 47 RM_Wake

12 N.C. 24 DVDD5V 36 AVDD 48 DVSS

3.2 Pin-Out Diagram

MUTE_REC

REGV_4V5
RM_Wake

GPIO_8

GPIO_7

GPIO_6

GPIO_5

GPI_2

GPI_1

AVDD
DVSS

N.C.
48

47

46

45

44

43

42

41

40

39

38

37

PDSW 1 36 AVDD

N.C. 2 35 N.C.

TEST 3 34 AVSS

GPIO_1 4 33 AVSS

GPIO_2

GPIO_3
5

6
CM6327A 32

31
AVDD

AVDD

GPIO_4 7 30 N.C.

LED_1 8 LQFP-48 29 VBIAS

LED_3 9 28 VREF

XTAL_I 10 27 N.C.

XTAL_O 11 26 MIC_IN

N.C. 12 25 AVSS
13

14

15

16

17

18

19

20

21

22

23

24
N.C.

HID_EN

N.C.

N.C.

I2C_SCLK

I2C_SDAT

I2C_INT

USB_DP

USB_DM

DVSS

REGV_3V3

DVDD_5V

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USB Single-Chip Audio Solution for Mono Microphone

3.3 Pin Signal Descriptions

No. Symbol Type Description

Power-down switch output

1 PDSW OD, 5V
(0: Normal operation; 1: Suspend)

2 N.C. N.C. N.C.

Test mode select

3 TEST DI, PD
(0: Normal Mode; 1: Test Mode)

4 GPIO_1 DIO General purpose I/O pin

5 GPIO_2 DIO General purpose I/O pin

6 GPIO_3 DIO General purpose I/O pin

7 GPIO_4 DIO General purpose I/O pin

8 LED_1 DO LED (Play or Record)

9 LED_3 DO LED (Mute Record)

10 XTAL_I DI Input pin for 12MHz oscillator

11 XTAL_O DO Output pin for 12MHz oscillator

12 N.C. N.C. N.C.

13 N.C. N.C. N.C.

HID bottom function enable

14 HID_EN DI, PU
(0: Disable; 1: Enable)

15 N.C. N.C. N.C.

16 N.C. N.C. N.C.

17 I2C_SCLK OD, DIO I2C serial clock/EEPROM 24c02 serial clock

18 I2C_SDAT OD, DIO I2C serial data/EEPROM 24c02 serial data

19 I2C_INT DO I2C interrupt output

20 USB_DP AIO USB D+

21 USB_DM AIO USB D-

22 DVSS P Digital ground

23 REGV_3V3 AO 5V->3.3V regulator output

24 DVDD5V P 5V power supply to internal regulator

25 AVSS P Analog ground

26 MIC_IN AI MIC input

27 N.C. N.C. N.C.

28 VREF AO 2.25V reference voltage output

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USB Single-Chip Audio Solution for Mono Microphone

29 VBIAS AO MIC bias voltage

30 N.C. N.C. N.C.

31 AVDD P 5V analog power for analog circuit

32 AVDD P 5V analog power for analog circuit

33 AVSS P Analog ground

34 AVSS P Analog ground

35 N.C. N.C. N.C.

36 AVDD P 5V Analog power for analog circuit

37 AVDD P 5V Analog power for analog circuit

38 REGV_4V5 AO 4.5V regulator output

39 N.C. N.C. N.C.

40 GPI_1 DI, PU General purpose input pin (VU)

41 GPI_2 DI, PU General purpose input pin (VD)

42 GPIO_5 DIO General purpose I/O pin

43 GPIO_6 DIO General purpose I/O pin

44 GPIO_7 DIO General purpose I/O pin

45 GPIO_8 DIO General purpose I/O pin

46 MUTE_REC DI, PU HID MIC Record Mute

47 RM_Wake DI, PU Remote wakeup pin to make PC resume from suspend

48 DVSS P Digital ground

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 CM6327A
USB Single-Chip Audio Solution for Mono Microphone

4 Block Diagram

CM6327A
GPIO/LED

PC USB Interface controller & 16-bit PGA

USB host interface signal processing 48KHz
ADC

Regulator ROM Register

Internal I2C
PLL

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CM6327A
USB Single-Chip Audio Solution for Mono Microphone

5 Ordering Information
Operating Ambient
Model Number Package Supply Range
Temperature

CM6327A 48-Pin LQFP, 7mm × 7mm × 1.45mm (Plastic) 0°C to +70°C DVdd = 5V, AVdd = 5V

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CM6327A
USB Single-Chip Audio Solution for Mono Microphone

6 USB Audio Topology and Descriptions

6.1 USB Audio Topology

IT FEA SEL OT

MIC USB STREAM

6.2 Device Descriptors

Offset Field Size Value (Hex) Description

0 bLength 1 12 Descriptor length

1 bDescriptorType 1 01 Device descriptor

2 bcdUSB 2 0110 USB 1.1-compliant

4 bDeviceClass 1 00 Device class specified by interface

5 bDeviceSubClass 1 00 Device subclass specified by interface

6 bDeviceProtocol 1 00 Device protocol specified by interface

7 bMaxPacketSize0 1 10 Endpoint zero packet size

8 idVendor 2 0d8c Vendor ID

10 idProduct 2 0134 Product ID

12 bcdDevice 2 0100 Device release number

14 iManufacturer 1 03 Manufacturer string descriptor index

15 iProduct 1 01 Product string descriptor index

16 iSerialNumber 1 00 or 03(*) Serial number string descriptor index

17 bNumConfigurations 1 01 Number of configurations

Note 1: When valid EEPROM is detected, Vendor ID and Product ID will be replaced by the content of the EEPROM
Note 2: iSerialNumber will be valid only if the external EEPROM contains this info

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USB Single-Chip Audio Solution for Mono Microphone

6.3 Configuration Descriptors

Offset Field Size Value (Hex) Description

0 bLength 1 09 Descriptor length

1 bDescriptorType 1 02 Configuration descriptor

2 wTotalLength 2 007f～00dd Total length of data returned for this configuration

Number of interfaces supported in configuration:

00: Control
4 bNumInterfaces 1 03
02: ISO-IN

03: INT-IN (HID)

5 bConfigurationValue 1 01 Configuration value

Index of string descriptor describing this

6 iConfiguration 1 00
configuration

Bus-powered with remote wakeup support: 8’ha0

(PWRSEL_1 = 1, HID_EN = 1)
a0 or
Bus-powered with no remote wakeup: 8’h80
80 or
(PWRSEL_1 = 1, HID_EN = 0)
7 bmAttributes 1 e0 or
Self-powered with remote wakeup support: 8’he0
c0
(PWRSEL_1 = 0, HID_EN = 1))

Self-powered with no remote wakeup: 8’hc0

(PWRSEL_1 = 0, HID_EN = 0))

Maximum power consumption from bus = 100mA:

8 bMaxPower 1 32
8’h32 (50x2 mA) (PWRSEL_2 = 1)

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USB Single-Chip Audio Solution for Mono Microphone

6.4 Standard HID Interface Descriptors

Offset Field Size Value (Hex) Description

0 bLength 1 09 Descriptor length

1 bDescriptorType 1 04 Interface descriptor

2 bInterfaceNumber 1 02 Interface number: 02

3 bAlternateSetting 1 00 Alternate interface

4 bNumEndpoints 1 01 Number of endpoints used by this interface

5 bInterfaceClass 1 03 HID interface class

6 bInterfaceSubClass 1 00 Subclass code

7 bInterfaceProtocol 1 00 Protocol code

8 iInterface 1 00 Interface string descriptor index

Class-specific HID Interface Descriptors

Offset Field Size Value (Hex) Description

0 bLength 1 09 Descriptor length

1 bDescriptorType 1 21 HID descriptor type

2 bcdHID 2 0100 HID class version

4 bCountryCode 1 00 No country code

5 bNumDescriptors 1 01 One HID class descriptor

6 bDescriptorType 1 22 Report Descriptor

7 wDescriptorLength 2 0032 / 001a HID class descriptor length in byte: 50 / 26 bytes

(Enable / Disable HID Button)

Standard HID Interrupt In Endpoint Descriptors

Offset Field Size Value (Hex) Description

0 bLength 1 07 Descriptor length

1 bDescriptorType 1 05 Endpoint descriptor

2 bEndpointAddress 1 87 IN endpoint, endpoint number: 7

3 bmAttributes 1 03 Interrupt endpoint

4 wMaxPacketSize 2 0010 Maximum packet size: 16 bytes

6 bInterval 1 01 1ms

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USB Single-Chip Audio Solution for Mono Microphone

7 Function Block Descriptions

7.1 I2C Interface

7.1.1 Master Mode

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USB Single-Chip Audio Solution for Mono Microphone

7.1.2 Slave Mode

“7-bit slave address = 7’b0111000”

On the MCU serial interface, the CM6327 serves as a slave device with bit rate up to 400Kbps (fast mode).
The MCU can write data to the CM6327A or read data from the CM6327A (no size limitations when using the
I2C Interface). Since the host side and MCU both have access to all the internal registers, access contention
when both host and MCU try to access the same register should be avoided upon application. The CM6327A’s
7-bit slave address is assigned as 7’b0111000.

When data is written by the MCU, the CM6327A will NOT transfer any interrupts to the PC until the INT bit of
the I2C control register has been set by the MCU. The USB host will keep polling the upward HID report every
1ms. When any button is pressed or released, or there is incoming MCU data, the CM6327A will transfer 16
bytes of HID report to the USB host.

In I2C Slave Mode, the CM6327A has one open-drain input pin (SCLK) from where it receives the serial clock
from the MCU, and one open-drain I/O pin (SDAT) from where it sends or receives serial signals to/from the
MCU. As shown below, SDAT should be stable when SCLK is high, and can transition only when SCLK is low.

START and STOP conditions shown below are the exception. Every transaction begins from a START, and
ends with a STOP, or another START (repeated START).

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USB Single-Chip Audio Solution for Mono Microphone

The figure below demonstrates a typical transaction. After every 8 bits sent by the transmitter, the receiver
should send one bit low for positive acknowledgement or one bit high for negative acknowledgement. After
the negative acknowledgement, a STOP or repeated START should follow. The next figure shows more
details about the acknowledgement bit. Note that SCLK is always driven by the master.

P
SDAT

Sr
MSB Acknowledgement Acknowledgment
Signal from Receiver Signal from Receiver

SCLK
S Sr
1 2 7 8 9 1 2 3-8 9 or
or
Sr P
ACK ACK

START or Repeated STOP or Repeated

START Condition START Condition

Data Transfer on the MCU Interface

The figure below shows a complete data transfer. After a START, the MCU should send a 7-bit slave address
(7’b0111000) first, with the 8th bit denoting a read transfer when it’s high, or a write transfer when it’s low.
The first acknowledgement always comes from the CM6327A.

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USB Single-Chip Audio Solution for Mono Microphone

During the write transfer, the MCU continues acting as the master, and the transfer direction is not changed.
The following figure gives an example of one byte write transfer.

MCU write:
S 0x70 0 addr 0 Byte 0 0 Byte 1 0 …. 0 Byte N 0 P

From CM6327A to MCU From MCU to CM6327A

S START condition P STOP condition

0 Positive acknowledge 1 Negative acknowledge

Byte N One byte data

The CM6327A’s slave address is 0x70, which will also tell the CM6327A when it’s receiving a write command.
CM6327A regards the first coming data byte as the register address. The second data byte is the data
content that the MCU writes at the register address. The CM6327A will auto-increment the register address
to the next register address for the following data writes.

The figure below shows an example of a read transfer. The MCU read command cannot set the register
address, so the MCU must use a write command to set the register address first, and then start the read
command. Because the CM6327A auto-increments the register address, the second data byte will be the
register data on the next address.

MCU read:
S 0x70 0 addr 0

S 0x71 0 Byte 0 0 Byte 1 0 ….. 0 Byte N 1 P

From CM6327A to MCU From MCU to CM6327A

S START condition P STOP condition

0 Positive acknowledge 1 Negative acknowledge

Byte n One byte of data

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CM6327A
USB Single-Chip Audio Solution for Mono Microphone

The figure below gives a complete picture of a typical transaction between the MCU and CM6327A. After a
START, the MCU should send a 7-bit slave address (7’b0111000) first, with the 8th bit denoting a read
transfer when it’s high, or a write transfer when it’s low.

MCU write:
S 0x70 0 addr 0 Byte 0 0 Byte 1 0 ….. 0 Byte N 0 P

MCU read:
S 0x70 0 addr 0

S 0x71 0 Byte 0 0 Byte 1 0 ….. 0 Byte N 1 P

From CM6327A to MCU From MCU to CM6327A

S START condition P STOP condition

0 Positive acknowledge 1 Negative acknowledge

Byte N One byte of data

During a write transfer, the MCU acts as the transmitter. The CM6327A will regard the first byte of data
received as the start register address. The following DATA bytes are the contents of the registers that the
MCU has requested. In a read transfer, two transactions are necessary. The MCU resets the start register
address by the first transaction, then direction changes for the MCU to receive data in the second
transaction.

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CM6327A
USB Single-Chip Audio Solution for Mono Microphone

7.1.3 EEPROM Data Format

Address Description

0x00 Magic word (“C”, 8’h43)

0x01 Magic word (“M”, 8’h4D)

EEPROM Content Setting (EEPROM_OPTION_1)

bit0: Manufacture String Valid? (0: No, 1: Yes)

bit1: Product String Valid? (0: No, 1: Yes)

bit2: Serial Number Valid? (0: No, 1: Yes)

0x02 bit3: Reserved

bit4: Recording (ADC) initial control Valid? (0: No, 1: Yes)

bit5: ADC gain range Control Valid? (0: No, 1: Yes)

bit6: Disable Selector unit? (0: No, 1: Yes)

bit7: Enable Remote Wakeup? (0: Disable, 1: Enable)

Recording (ADC) initial-L (EEPROM_OPTION_2)

bit[5:0]: ADC(unit Fa) initial Volume L-byte

0x03 (6’h2E ~ 6’h00, 30~ -16dB, -1dB/step)

bit6: Mute_fa (ADC) initial Value (0: Un-Mute, 1: Mute)

bit7: Reserved

Recording (ADC) initial-H (EEPROM_OPTION_3)

(1)bit[3:0]: ADC (Unit Fa) initial volume H-byte

(4’hf ~ 4’h0, 15 ~ 0dB, -1dB/step)

0x04
Bit[4]: control ADC HP filter by EEPROM (0 : No, 1 : Yes)

Bit[5]: ADC HP filter enable (0 : Disable, 1 : Enable)

Bit[7:6]: Reserved

Recording (ADC) max range Control_L (EEPROM_OPTION_4)

0x05
bit[7:0]: ADC (Unit fa) max. Volume[7:0]

Recording (ADC) max. range Control_H (EEPROM_OPTION_5)

0x06
bit[7:0]: ADC (Unit fa) max. Volume[15:8]

Recording (ADC) min range Control_L (EEPROM_OPTION_6)

0x07
bit[7:0]: ADC (Unit fa) min. Volume[7:0]

Recording (ADC) min. range Control_H (EEPROM_OPTION_7)

0x08
bit[7:0]: ADC (Unit fa) min. Volume[15:8]

0x09 Reserved

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USB Single-Chip Audio Solution for Mono Microphone

0x0a Reserved

Manufacture string 1 length: this number doesn’t include the first 2 bytes of the
0x0b
string descriptor, and its unit is one Unicode word (EEPROM_OPTION_A)

Product string 2 length: this number doesn’t include the first 2 bytes of the
0x0c
string descriptor, and its unit is one Unicode word (EEPROM_OPTION_B)

Serial number string 3 length: this number doesn’t include the first 2 bytes of
0x0d
the string descriptor and its unit is one Unicode word (EEPROM_OPTION_C)

0x0e VID (low byte) (EEPROM_OPTION_D)

0x0f VID (high byte) (EEPROM_OPTION_E)

0x10 PID (low byte) (EEPROM_OPTION_F)

0x11 PID (high byte) (EEPROM_OPTION_10)

misce reg (EEPROM_OPTION_11)

Bit0: Boot gain (volume boot gain 18dB; using digmic boost gain =18dB)
0x12
Bit1: Enable PLL adjustment (0: No, 1: Yes)

Bit2: Reserved (0 : default )

0x13 Reserved

0x14 ~ 0x4f Reserved (60 bytes)

Manufacture string (X bytes): only fill one byte of Unicode in this content, HW
0x50 ~0x(50+X-1)
will add the other byte 0x00

0x(50+X)~ Product string (Y bytes): only fill one byte of Unicode in this content, HW will

0x(50+X+Y-1) add the other byte 0x00

0x(50+X+Y)~ Serial number string (Z bytes): only fill one byte of Unicode in this content, HW

0x(50+X+Y+Z-1) will add the other byte 0x00

Others Reserved

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CM6327A
USB Single-Chip Audio Solution for Mono Microphone

8 Electrical Characteristics
8.1 Absolute Maximum Rating

Symbol Parameter Value Unit

Dvmin Min. digital supply voltage – 0.3 V

Dvmax Max. digital supply voltage +6 V

Avmin Min. analog supply voltage – 0.3 V

Avmax Max. analog supply voltage +6 V

Dvinout Voltage on any digital input or output pin –0.3 to +5.5 V

Avinout Voltage on any analog input or output pin –0.3 to +5.5 V

0
Tstg Storage temperature range -40 to +125 C
0
Tj Junction operating temperature (commercial) 0~+115 C

ESD (HBM) ESD human body mode 4000 V

ESD (MM) ESD machine mode 400 V

Latch Up Class-3 200 mA

8.2 Operation Conditions

Operation conditions

Min Typ Max Unit

Analog supply voltage 4.35 5.0 5.5 V

Digital supply voltage 4.35 5.0 5.5 V

Operation power consumption - 33 - mA

Standby power consumption - 28 - mA

Suspend mode power consumption - 410 - uA

0
Operating ambient temperature 0 - 70 C
o
*Notes: Test environment under 25 C, 5.0V, 48K sample rate;
Max. output is playing 1K full-scale sine wave, typical output is playing music

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USB Single-Chip Audio Solution for Mono Microphone

8.3 Electrical Parameters

Min Typ Max Unit

THD + N (20 ~ 20KHz) -89 - -96 dB

Dynamic range - 96 - dB

Frequency response 48KHz 20 - 20K Hz

Frequency response 44.1KHz 20 - 20K Hz

Input voltage (rms) - 1.2 - Vrms

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USB Single-Chip Audio Solution for Mono Microphone

9 Analog Performance
9.1 ADC Frequency Response

9.2 ADC THD + N

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USB Single-Chip Audio Solution for Mono Microphone

REFERENCE
 USB specification 2.0-compliant
 USB audio device class specification 1.0-compliant

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－End of Datasheet－

C-MEDIA ELECTRONICS INC.

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TEL：+886-2-8773-1100

FAX：+886-2-8773-2211

E-MAIL：sales@cmedia.com.tw

Disclaimer:
Information furnished by C-Media Electronics Inc. is believed to be accurate and reliable. However, no responsibility is assumed by C-Media Electronics Inc. for its use, nor for any
infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or
otherwise under any patent or patent rights of C-Media. Trademark and registered trademark are the property of their respective owners.

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