AKM AK5371VQ 2ch a/d converter with usb i/f Datasheet

[AK5371]
ASAHI KASEI
AK5371
2ch A/D Converter with USB I/F
Features:
General Description
USB-IF Certified
The AK5371 is stereo A/D converter with USB I/F. The
AK5371 integrates USB serial interface engine, USB
transceiver, audio class processing unit, endpoints, and high
quality 2 channel AD converter into the chip.
Incorporates USB Audio Controller
USB Serial Interface Engine
Audio Class Encoder/Decoder
2 Endpoints (FIFO)
USB transceiver
16 bit A/D Converter
2 channels
Mute/Volume Control
A/D S/N: 84dBA (44.1kHz, Gain = 0dB)
Low Power Dissipation
Normal Operation: 26mA
Suspend Mode: < 1uA
Programmable Gain Amplifier (IPGA)
+24dB to –31dB @1dB Step
20dB Pre-amplifier
On-chip PLL
5 Sampling Frequencies support
8kHz, 11.025kHz
22.05kHz, 44.1kHz, 48kHz
As the AK5371 incorporates PLL, it can support several
sampling frequencies, 8kHz, 11.025kHz, 22.05kHz, 44.1kHz,
and 48kHz with only one crystal. Moreover, the AK5371
integrates volume control, and mute function.
Not only power consumption at normal operation is very
low, but also the current at suspend mode is less than 1µA.
The AK5371 includes 20dB fixed gain pre-amplifier. In
addition to this, as the AK5371 also incorporates IPGA which
can amplify the microphone signal up to +24dB, total gain is
44dB maximum.
The AK5371 has EEPROM I/F for customizing Device
Descriptor and String Descriptor. By connecting 1K bit, 2K
bit, or 4Kbit MicrowireTM type EEPROM, the AK5371 can
customize Vendor ID, Product ID in Device Descriptor, and
String Descriptor.
This device is good for not only business application such as
conferencing but also games, voice recognition, and Karaoke.
EEPROM I/F
can customize Device Descriptor,
and String Descriptor
Related Documents
For the detail of USB specification, and Audio Class, please
refer to the following documents.
Single Power Supply, Low Power
+3.3±0.3 Volts
Universal Serial Bus Specification Revision 1.1
Universal Serial Bus Device Class Definition for Audio
Devices, Revision 1.0
Package
48pin LQFP
MS0103-E-00
MS0103-E-00
2001/06
1
ASAHI KASEI
[AK5371]
Block Diagram
microwire
BGND
BIASSEL
VA VREF VCOM
DGND
AGND VD
SUSN
EEPROM
(1K bit)
CS
SK
EPAO
MICBIAS
MICR
Config/String
ROM
Common Voltage
VREF
Mute
&
Volume
control
20dB
+
Audio Class
Decoder
EndPoint0
OUT_FIFO
Audio Class
Encoder
EndPoint0
IN_FIFO
AMPR2I
20dB
+
EPEN
Serial
Interface
Engine
Testmode1,2,3
16bit
ADC
+
EPDI
EPSEL
AMPR1O
MICL
EEPROM
Control
EndPoint1
IN_FIFO
TEST
SystemCLK
AMPL1O
AMPL2I
adCLK
+
USB
Transceiver
PLL
AMPR2O
AMPL2O
XTLIN
DP
DN
XTLOUT RSTN
LFLT2
LFLT1
CRYSTAL
Ordering Guide
AK5371VQ
AKD5371
0 ∼ +70 °C
48pin LQFP (0.5mm pitch)
Evaluation Board
Pin Layout
NC
EPDI
EPEN
45
1
EPSEL
NC
RSTN
SUSN
NC
NC
DP
DN
NC
VD
40
NC
DGND
35
CS
NC
TESTMODE3
TEST
5
NC
XTALOUT
XTALIN
30
VREF
LFLT1
AGND
10
VA
BIASSEL
NC
15
25
20
NC
AMPR2O
AMPR2I
AMPR1O
MICR
NC
AMPL2O
AMPL2I
AMPL1O
MICL
MICBIAS
VCOM
NC
MS0103-E-00
MS0103-E-00
TESTMODE1
NC
TESTMODE2
LFLT2
EPAO
SK
BGND
2001/06
2
ASAHI KASEI
[AK5371]
Pin/Function
No.
1
2
3
4
5
6
7
8
9
Signal Name
VD
DGND
BGND
NC
TESTMODE3
XTALOUT
XTALIN
TESTMODE2
LFLT1
10
LFLT2
O
A
11
BIASSEL
I
D
12
13
14
15
NC
NC
VCOM
MICBIAS
O
O
A
A
16
17
18
19
20
21
22
23
24
MICL
AMPL1O
AMPL2I
AMPL2O
NC
MICR
AMPR1O
AMPR2I
AMPR2O
I
O
I
O
I
O
I
O
A
A
A
A
A
A
A
A
MS0103-E-00
MS0103-E-00
I/O
P
P
P
I
O
I
I
O
Ana / Dig
D
D
D
D
A
A
A
A
Description
Digital Power Supply, 3.3V
Digital Ground,0V
Bulk Ground, 0V
No Connection
Please tie down to AGND for normal operation.
Crystal Oscillator Output, Connect Crystal Resonator
Crystal Oscillator Input, Connect Crystal Resonator
Please tie down to AGND for normal operation.
adPLL loop filter Pin. Connect 51kΩ resistor and 8200pF
capacitor in series externally.
System clock PLL loop filter Pin. Connect 18kΩ resistor and
6800pF capacitor in series externally.
MIC BIAS Select Pin
Select MICBIAS Output
"L": VA(through switch)
“H”: VREF buffer output
No Connection
No Connection
Analog Common Voltage Reference Pin
Voltage Reference Output for the Microphone’s bias voltage
When this chip goes into Suspend mode, this pin goes to Hi-Z.
Left Channel Microphone Input
Left Channel 1st Amplifier Output Pin
Left Channel 2nd Amplifier Input Pin
Left Channel 2nd Amplifier Output Pin
No Connection
Right Channel Microphone Input
Right Channel 1st Amplifier Output Pin
Right Channel 2nd Amplifier Input Pin
Right Channel 2nd Amplifier Output Pin
2001/06
3
ASAHI KASEI
[AK5371]
No.
25
26
27
28
29
30
31
32
Signal Name
NC
VA
AGND
VREF
NC
TESTMODE1
NC
TEST
33
CS
34
SK
35
EPAO
O
D
EEPROM Address Output Pin
36
37
38
NC
NC
EPDI
I
D
No Connection
No Connection
EEPROM Data Input Pin (This pin is internally pulled down)
39
EPEN
I
D
40
EPSEL
I
D
41
42
NC
SUSN
O
D
43
RSTN
I
D
44
45
46
NC
NC
DP
I/O
D
47
48
DN
NC
I/O
-
D
-
EEPROM Enable Pin
"H" : Read Device Descriptor, String Descriptor from EEPROM
“L” : Read Device/String Descriptor from internal ROM.
Note that CS,SK,EPDI,EPAO is Hi-Z when EPEN is “L”
EEPROM Select Pin
“L” : 1Kbit Type EEPROM is connected.
“H” : 2Kbit/4Kbit EEPROM is connected
If EEPROM is not used, EPSEL should be tied to DGND.
No Connection
Suspend Status Pin
"L" : Suspend State
"H" : Normal Operation
Reset Pin, Low input makes the chip reset sate.
Schmitt Trigger input.
No Connection
No Connection
USB bus Non-Inverting pin.
Because AK5371 is full speed mode device, 1.5kΩ resistor will
be connected between D+ node to VD.
USB bus Inverting Pin.
No Connection
MS0103-E-00
MS0103-E-00
I/O
P
P
O
I
I/O
Ana / Dig
A
A
A
A
D
Description
No Connection
Analog Power Supply, 3.3V
Analog Ground,0V
ADC Common Voltage Reference Pin.
No Connection
Please tie down to AGND for normal operation.
No Connection
Please tie down to AGND for normal operation.
O
D
EEPROM I/F Chip Select Pin
O
D
Serial Clock Pin
2001/06
4
ASAHI KASEI
[AK5371]
Absolute Maximum Rating
AGND, DGND=0V
Parameter
Power Supplies
Analog
Digital
|DGND-AGND|
Input Current (any pins except for supplies)
Analog Input Voltage
Digital Input Voltage
Ambient Temperature
Storage Temperature
Note 1. All voltages with respect to ground
Symbol
Min
Max
Units
VA
VD
∆GND
IIN
VINA
VIND
Ta
Tstg
-0.3
-0.3
4.5
4.5
0.3
±10
VA+0.3
VD+0.3
70
125
V
V
V
mA
V
V
°C
°C
-0.3
-0.3
0
-40
Warning: Operation at or beyond these limits may results in permanent damage to the device. Normal operation
is not guaranteed at these extremes.
Recommended Operating Condition
AGND, DGND=0V
Parameter
Power Supplies
Analog
Digital
Symbol
Min
typ
Max
Units
VA
VD
3.0
3.0
3.3
3.3
3.6
3.6
V
V
All voltages with respect to ground.
* AKM assumes no responsibility for the usage beyond the condition in this datasheet.
MS0103-E-00
MS0103-E-00
2001/06
5
ASAHI KASEI
[AK5371]
Analog Characteristics
Ta=25°C,VA=VD=3.3V, Signal Frequency=1kHz, Sampling Frequency Fs=44.1kHz BW=20Hz – 20kHz, Test Mode; unless
otherwise specified
Parameter
Min
typ
Max
Units
Stereo ADC (2 channel)
Resolution
16
bits
S/N (A weight)
(AMPR2I/AMPL2I input)
84
dBA
(IPGA are set to 0dB)
USB Normal Mode
S/(N+D)
(-1dB analog input)
70
dB
(IPGA are set to 0dB)
USB Normal Mode
nd
MIC Amplifier (2
Stage) <IPGA>Characteristics
Full Scale Input Voltage
1.5
1.7
1.9
Vp-p
Gain Control Range
-31
+24
dB
Step Size
0
1.0
2.0
dB
Input Impedance @AMPR2I/AMPL2I pin
40
KΩ
st
MIC Amplifier (1
Stage)
Gain range
+20
dB
Input Impedance @MICR/MICL
10
20
KΩ
S/N (A weight) @MICR/MICL to AMPR1O/AMPL1O
77
dBA
MIC Bias (VA)
Output Voltage
when 4.7KΩ resistor connected
2.0
Vdc
Output Impedance
200
500
Ω
Output Current
2
mA
MIC Bias (Buffer Amp)
Output Voltage
when 300Ω resistor connected
1.9
2.2
2.5
Vdc
Output Current
2
mA
Power Supplies
Analog
17
25
mA
Digital
9
15
mA
26
40
mA
Total
Power Down (Suspend Mode)
0
160
uA
FILTER CHARACTERISTICS
(Ta=25°C VA, VD =3.0 - 3.6 V ; fs = 44.1 kHz)
Parameter
Symbol
A/D Digital Filter
(Decimation LPF)
Passband
+/- 0.2 dB
PB
Stopband
SB
Passband Ripple
PR
Stopband Attenuation
SA
Group Delay
GD
A/Ddigital Filter (HPF)
Frequency Response
-3 dB
FR
-0.5 dB
-0.1 dB
MS0103-E-00
MS0103-E-00
Min
typ
0
26.5
Max
Units
17.64
KHz
KHz
dB
dB
ms
+/- 0.2
68
0.5
6.85
19.2
44.9
Hz
Hz
Hz
2001/06
6
ASAHI KASEI
[AK5371]
Digital DC Characteristics
Ta=0 - 70°C; VD=3.0 - 3.6V; DGND=0V Measurement under static state
All digital pins except DP, DN. Schmitt hysteresis level of RST pin and levels of all test pins will not be tested.
Parameter
EPDI, EPEN, EPSEL, pin “H” level input voltage
EPDI, EPEN, EPSEL pin “L” level input voltage
RSTN pin “H” level voltage
RSTN pin “L” level voltage
CS, SK, EPAO, SUSN pin “H” level output
voltage
IOH = 2mA
CS, SK, EPAO, SUSN pin “L” level output
voltage
IOL = -2mA
Input Leakage Current
Symbol
VIH
VIL
VIHR
VILR
VOH
Min
70%VD
Typ
Max
Units
V
V
V
V
V
30%VD
2.0
0.8
2.4
VOL
0.6
V
Iin
±10
µA
Switching Characteristics
Ta=25°C, VA=VD=3.3V
Parameter
Symbol
Min
Typ
Max
Master Clock Frequency
MCLK
11.2896
Reset input width @RSTN pin(low active)
Wrst
1.0
DP,DN Single Ended Receiver Threshold
for H level
VseH
2.0
for L level
VseL
0.8
Time Width for USB Reset Signal Recognition*1
Trst_rec
2.7
DP<VseL & DN< VseL to USB Reset mode
Device Ready Time from USB Reset
Tdrr
10
Ready for transaction after reset
Time Width for Suspend Recognition
Tsus_rec
3.0
Idle state ( DP > VseL & DN < VseL )
to Suspend mode
Resume Time from Suspend
First flip of DP/DN from Idle sate
Tresm
30
To Device Ready*)
Device Ready: VREF, X’tal oscillator, and PLL get stable and bus transaction with normal rate is ready.
min 20ms
resume time
VD
Units
MHz
us
V
µs
ms
ms
ms
min 10ms
resume recovery time
Resume
DP
DN
RSTN
PLL
Clock
Tdrr
Trst_rec
Reset Mode
Device
Connected
Figure 1. Mode change with respect to BUS States 1 (Power on and device connected)
MS0103-E-00
MS0103-E-00
2001/06
7
ASAHI KASEI
[AK5371]
Tsus_rec
VD”H”
D+
DRST”H”
PLL
Clock
Tresm
Figure 2. Mode Change with respect to Bus States 2 (Bus transactions)
Transmitter Characteristics
Ta=25°C; VD=3.3V; DGND=0V; CL=50pF
Parameter
Symbol
Data Rate
DR
Output Impedance (Hi)
Roh
DP, DN
Rol
DP, DP
Vohd
Vold
Iolk
Trf/Tff
Trfm
Vcrs
DP, DN
DP, DN
DP, DN
DP, DN
DP, DN
DP, DN
Output Impedance (Lo)
“H” level Output Voltage
“L” level Output Voltage
Tri-state Leakage Current
Rise/Fall Time
Rise/Fall Time Matching
Crossover Point
Pins
DP,DN
Trf
Trs
Conditions
Min
11.97
DP, DN=”H”
at Iout = -10mA
DP, DN=”L”
at Iout = 10mA
at Iout =-200uA
at Iout =2.2mA
0 < DP, DN< 3.3V
Tff
Typ
12
Max
12.03
36
Ω
36
Ω
2.8
-10
4
Units
MHz
10
100
1.65
0.3
10
20
V
V
µA
ns
%
V
Tfs
90%VDD
DP, DN
10%VDD
Figure 3. Rise/Fall Time
Vcrs
DP, DN
Figure 4. Crossover Point
MS0103-E-00
MS0103-E-00
2001/06
8
ASAHI KASEI
[AK5371]
Receiver Characteristics
Ta=25°C; VD=3.3V; DGND=0V
Parameter
Symbol
Common Mode Range
CMR
Differential Input Sensitivity
DIS
Schmitt High Level Voltage
Vihs
Schmitt Low Level Voltage
Vils
Pins
DP, DN
DP, DN
DP, DN
DP, DN
Conditions
Min
0.8
200
2.0
Typ
Max
0.8
Units
V
mV
V
V
Vihs
DP, DN
Vils
Figure 5. Schmitt Level Voltage
MS0103-E-00
MS0103-E-00
2001/06
9
ASAHI KASEI
[AK5371]
Overview of AK5371
The AK5371 is the advanced stereo A/D converter, which converts analog signal into USB audio class formats. As the AK5371
incorporates all functions to build USB Audio Input Device, the AK5371 doesn’t require additional micro-controller, memory, and a
transceiver. Moreover, as the AK5371 also has 20dB fixed gain pre-amplifier in addition to programmable gain amplifier (IPGA)
whose range is from +24dB to –31dB, this device is suitable for USB microphone, especially microphone array. USB microphone
can be manufactured easily by only four main components; the AK5371, one crystal, one regulator, and microphone unit(s). As the
AK5371 also has EEPROM interface, descriptors can be customized easily. The AK5371 includes the following blocks:
1.
2 channel 16bit A/D converter
a)
84dBA@fs=44.1kHz
2.
Programmable Gain Amplifier (IPGA)
a)
Gain Range: from +24dB to -31dB,
b) Gain Step: 1dB/step
3.
Fixed Gain Preamplifier
a) 20dB
4.
FIFO
Synchronization between A/D converter and USB bus
a) Memory Size 400 bytes (16bit wide x 100 depth x 2 channel)
5.
PLL
a)
b)
11.2896MHz crystal
Two PLLs
- A/D_PLL: generate clock for fs=8kHz, 48kHz
- System_PLL : generate USB system clock
6.
Audio Format
a)
supports 5 frequencies : 8kHz, 11.025kHz, 22.05kHz, 44.1kHz, 48kHz
b) 2 audio formats
- mono 16bit LSB first
- stereo 16bit LSB first
7.
USB Serial Interface Engine
a) Process USB Standard Requests
8.
Control block of Audio Device Class
a) Translate internal A/D format to USB audio class format
b) Process USB Audio Class Request
- Mute
- Gain/Attenuation
- Sampling Frequency Control
9.
USB transceiver
10.
EEPROM I/F
Microwire (4-wire) type EEPROM can be used to customize Device/String Descriptor.
- 1K bit (AK93C45A)
- 2K bit (AK93C55A)
- 4Kbit (AK93C65A)
11.
USB Suspend/Resume Support
The AK5371 supports 5 sampling frequencies (8kHz, 11.025kHz, 22.05kHz, 44.1kHz, 48kHz). In order to support these
frequencies, the AK5371 incorporates PLL, which generates system clock and master clock for fs=8kHz, and 48kHz
Mute, volume and audio format including sampling frequency are controlled by USB audio class request.
The AK5371 goes to suspend mode when the device doesn’t receive SOF for the period more than 3ms. All blocks including
master clock stop the function to observe USB specification, 500µA , until receiving the resume signal. The AK5371 notifies the
current state (normal state or suspend state) by SUS_N pin.
As the AK5371 has Microwire EEPROM I/F, the vendors can customize iManifacterer, iProduct, and the related strings to their
own ID, and string.
MS0103-E-00
MS0103-E-00
2001/06
10
ASAHI KASEI
[AK5371]
Descriptor Overview
When the device is connected to USB bus, the host assigns specific address to the device. Then the host reads the device
information, which is called as descriptor, through default pipe (Endpoint 0). The AK5371 consists of one Device Descriptor, one
Configuration Descriptor, two Interface Descriptors, and two Endpoint Descriptors.
Figure 6 shows Descriptor’s hierarchy.
Device
Device
Descriptor
Configuration
Configuration
Descriptor
Standard Audio Control
Interface Descriptor
Standard AS Interface
Descriptor Alt. Setting 0
Class-Specific Audio Control
Interface Descriptor
Interface 0
Interface 1
Standard AS Interface
Descriptor Alt. Setting 1
Standard AS Interface
Descriptor Alt. Setting 2
Class-Specific Audio Streaming
Interface Descriptor
Class-Specific Audio Streaming
Interface Descriptor
Class-Specific AS Format Type
Descriptor
Class-Specific AS Format Type
Descriptor
Standard AS Isochronous
Endpoint Descriptor
Standard AS Isochronous
Endpoint Descriptor
Class-Specific AS Isochronous
Endpoint Descriptor
Class-Specific AS Isochronous
Endpoint Descriptor
Class-Specific Descriptor
StandardInterface Descriptor
Endpoint
(IN)
Figure 6. Descriptor Hierarchy
MS0103-E-00
MS0103-E-00
2001/06
11
ASAHI KASEI
[AK5371]
Audio Format of the AK5371
The AK5371 supports two audio formats: 16bit/mono and 16bit/stereo. This feature can avoid the unnecessary occupation of USB
bandwidth. 16bit/mono is assigned to <Interlace 1, Alt1>, 16bit/stereo is assigned to <Interface 1, Alt2>. The A/D data on USB bus
is LSB first, Left channel first. When 16bit/mono audio format is selected, the AK5371 outputs left channel data on the USB bus.
Audio format is changed by “Set Interface” Request.
Synchronization
The AK5371 operates as Asynchronous Device. A/D converter in the AK5371 operates asynchronously with USB SOF timing. The
data from A/D converter are sent continuously to a buffer memory while the data are burstly transferred at the interval of SOF on the
USB. In order to arbitrate the difference of timing, AK5371 has a FIFO memory with a capacity of 2-frame depth .The average
sampling rate calculating from USB frame should be in accordance with A/D sampling rate (fs).
The AK5371 sends all A/D samples that were stored in the last frame to avoid overflow or underflow of FIFO. The following figure
shows an example. When sampling frequency is set to 44.1kHz, the AK5371 sends 45 samples once per ten times, and sends 44
samples in other frames. Average frequency is 44.1kHz. See Figure 7.
N Frame
(N+1) Frame
44 samples
44 samples
(N+9) Frame
45 samples
(N+10) Frame
44 samples
Figure 7. Synchronization
Power Management Control
When idle state continues for 3ms, the AK5371 goes to suspend state and forces almost all blocks including PLL, ADC block and
mic bias into stopping in order to observe 500µA, which is USB suspend current requirement.
The device resumes the normal operation within 30ms after the device receives resume signal.
In the normal operation, MICBIAS outputs the voltage to supply the microphone’s bias voltage.
SUSN pin shows USB bus status; suspend mode (“L") or normal operation (“H").
SUSN pin can be used for external power control.
The AK5371 is very low power device at both normal state and suspend state. However, note that USB suspend current requirement,
500µA, specifies the current which is totally consumed by not only the AK5371, by also regulator(s), and resistors. Therefore, low
power regulator should be selected to design USB microphone.
Feature Unit Control & Frequency Control
When the AK5371 receives “SET_FEATURE_UNIT_CONTROL” request, the device decodes the request and sets the value. Note
that only CUR value is valid for “SET_FEATURE_UNIT_CONTROL” request, and that MIN/MAX/RES value is invalid.
When the AK5371 receives “GET_FEATURE_UNIT_CONTROL” request, the device decodes the request and returns the value to
the host. CUR/MAX/MIN/RES value is valid for "Get Volume Request", but only CUR value is meaningful for "Get Mute
Request".
When the AK5371 receives “SET_ENDPOINT_CONTROL” request, it changes sampling frequency(fs). If fs is not supported, the
device forces to set the appropriate fs which it supports. When the AK5371 receives “GET_ENDPOINT_CONTROL” request, it
sends back the current value to the host.
MS0103-E-00
MS0103-E-00
2001/06
12
ASAHI KASEI
[AK5371]
EEPROM I/F
The AK5371 has EEPROM I/F for customizing Device Descriptor, and String Descriptor. idVendor(2byte), idProduct(2byte),
bcdDevice(2byte), iManufacturer(1byte), iProduct(1byte) in Device Descriptor and related String Descriptor can be customized.
MicrowireTM type, 1K bit, 2K bit, or 4K bit EEPROM can be used. Note that word length of iManufacterer and
iProduct is fixed to 52 bytes each for 1K bit EEPROM, 102 bytes for 2K/4K bit EEPROM.
The AK5371 automatically reads Device Descriptor from the EEPROM and stores internal memory after USB reset.
When the AK5371 receives “GET String Descriptor" request, the AK5371 starts reading from EEPROM. The AK5371 continues to
send NAK packet while it is reading String from EEPROM.
Memory mapping of EEPROM is the following.
Device Descriptor (18 bytes)
String Descriptor Lang ID (4 bytes index = 0)
String Descriptor iManufacturer (52 or 102bytes index =1)
String Descriptor iProduct (52 or 102 bytes index = 2)
Note that EEPROM address is 16bit boundary.
1K bit
(AK93C45A)
00h - 08h
09h - 0Ah
0Bh - 24h
25h - 3Eh
2K/4K bit
(AK93C55A / 65A)
00h - 08h
09h - 0Ah
0Bh - 3Dh
3Eh - 71h
If 2K/4K bit EEPROM is used, EPSEL pin should be tied to VD. if 1K bit EEPROM is connected to the device, EPSEL should be
tied to digital ground.
Device Descriptor and String Descriptor should be stored in EEPROM before the AK5371 is powered up. EPEN pin should be tied
to "H" to activate if Descriptors are read from external EEPROM.
If internal ROM is used, not only EPEN pin but also EPSEL pin should be tied to DGND. Note that CS pin, SK pin, and EPAO
pin are Hi-Z state when EPEN is “L”. EPDI pin is internally pulled down.
MS0103-E-00
MS0103-E-00
2001/06
13
ASAHI KASEI
[AK5371]
System Block Diagram
The following figure shows the system connection diagram. This is an example which uses external 1K bit EEPROM (AK93C45A)
as Device and String Descriptor. If EEPROM is not used, EPEN pin should be tied to DGND.
Ceramic capacitors (0.1uF) for VA pin, VD pin, VREF pin and VCOM pin should be located as near as possible.
<REMARK> This drawing does NOT mean physical pin locations/ordering
10uH
10Ω
Regulator
0.1u
10u
R1:4.7k
0.1u 4.7u 0.1u 4.7u
0.1u 100u
0.1u
0.1u
4.7u
4.7u
0.1u
56k
R1:4.7k
R0
VA AGND BGND VD DGND
VREF
VCOM
MICBIAS
10u
RSTN
3300p
CS
SK
EPAO
EPDI
100u
0.1u
C1:1.0u<
C2:0.33u
Phone Jack
C1:1.0u<
STEREO SW C2:0.33u
MICR
AMPR1O
Testmode 1
Testmode 2
Testmode 3
Test
AMPR2I
MICL
AMPL1O
1.5k
D+
DP
AMPL2I
AMP2RO
EEPROM
AMP2O
DN
LFLT1,2 XTALIN XTALOUT
51k
C3:1000p C3:1000p
8200p
18k
6800p 15p
D-
GND
11.2896M
15p
To Host/Hub
5V
GND
analog
GND
digital
GND
C1 is specified for lower end cut-off frequency
C3 forms Anti-aliasing filter in conjuction with the
internal resistor at AMPR2O/AMPL2O
R0: 0Ω resister when BIASSEL is Low
300Ω (TBD) resister when BIASSEL is High
MS0103-E-00
MS0103-E-00
2001/06
14
ASAHI KASEI
[AK5371]
AK5371 Descriptors Specification
1 Device descriptor
Offset
0
1
2
4
5
6
7
8
10
12
14
15
16
17
Field
bLength
bDescriptorType
bcdUSB
bDeviceClass
bDeviceSubClass
bDeviceProtocol
bMaxPacketSize0
idVendor
idProduct
bcdDevice
iManufacturer
iProduct
iSerialNumber
bNumConfigurations
Size
1
1
2
1
1
1
1
2
2
2
1
1
1
1
Value
0x12
0x01
0x0110
0x00
0x00
0x00
0x08
0x0556
0x0002
0x0001
0x01
0x02
0x00
0x01
Description
Size of this descriptor in bytes
DEVICE descriptor
1.10 – current revision of USB spec.
Device defined at Interface level
Unused
Unused
8 bytes
AKM’s Vendor ID
00 means Audio Product, 02 is AKMproduct ID ,
Device release code
“AKM”
“AK5371”
Unused
One configuration
2 Configuration Descriptor
The configuration block consists of a configuration descriptor followed by interface, endpoint, and class-specific
descriptors.
Offset
Field
Size
Value
Description
0
bLength
1
0x09
Size of this descriptor
1
bDescriptorType
1
0x02
CONFIGURATION descriptor
2
wTotalLength
2
0x00B1
Length of entire configuration block
Total 177 bytes including this interface
descriptor.
Two interfaces
4
bNumInterfaces
1
0x02
5
bConfigurationValue
1
0x01
Index of this configuration
6
iConfiguration
1
0x00
Null string
7
bmAttributes
1
0x80
Bus Powered Device
8
MaxPower
1
0x2D
Power consumption: 90mA
3 Interface Descriptor
3.1 Standard Audio Control Interface descriptor
3.1.1 This descriptor describes a standard interface which includes USB class code and the index to class-specific
information.
Offset
Field
Size
Value
Description
0
bLength
1
0x09
Size of this descriptor
1
bDescriptorType
1
0x04
INTERFACE descriptor
2
bInterfaceNumber
1
0x00
Index of this interface
3
bAlternateSetting
1
0x00
Index of this setting
4
bNumEndpoints
1
0x00
Endpoint 0
5
bInterfaceClass
1
0x01
AUDIO
6
bInterfaceSubclass
1
0x01
AUDIO_CONTROL
7
bInterfaceProtocol
1
0x00
Unused
8
iInterface
1
0x00
null string
MS0103-E-00
MS0103-E-00
2001/06
15
ASAHI KASEI
[AK5371]
3.2 Class-specific Audio Control Interface
3.3 Class-specific Audio Control Interface Header Descriptor
3.3.1
Offset
0
1
2
3
5
7
8
Contains general information about the audio device.
Field
Size
Value
Description
bLength
1
0x09
Size of this descriptor
bDescriptorType
1
0x24
CS_INTERFACE
bDescriptorSubtype
1
0x01
HEADER subtype
bcdADC
2
0x0100
Revision of class specification – 1.0
wTotalLength
2
0x0028
Total size of class-specific Audio Control
Interface descriptors (includes this
descriptor)
bInCollection
1
0x01
Number of streaming interfaces
baInterfaceNr(1)
1
0x01
Streaming interface number 1 belongs to
this audio control interface.
3.3.2
Input terminal descriptor
This descriptor describes the signal coming through the input port NumChannels is 1(monaural) and
ChannelConfig is set no position. Terminal type is Microphone.
Offset
Field
Size
Value
Description
0
bLength
1
0x0C
Size of this descriptor
1
bDescriptorType
1
0x24
CS_INTERFACE
2
bDescriptorSubtype
1
0x02
INPUT_TERMINAL subtype
3
bTerminalID
1
0x01
ID of this terminal
4
wTerminalType
2
0x0201
Terminal is Microphone
6
bAssocTerminal
1
0x02
ID of associated Output Terminal is 0x02
7
bNrChannels
1
0x02
Two channels (Stereo)
8
wChannelConfig
2
0x0003
Left/Right Front
10
iChannelNames
1
0x00
Unused
11
iTerminal
1
0x00
Unused
3.3.3
Output terminal descriptor
This descriptor describes the USB stream to host.
Offset
Field
Size
Value
0
bLength
1
0x09
1
bDescriptorType
1
0x24
2
bDescriptorSubtype
1
0x03
3
bTerminalID
1
0x02
4
wTerminalType
2
0x0101
6
bAssocTerminal
1
0x01
7
bSourceID
1
0x03
8
iTerminal
1
0x00
3.3.4
Offset
0
1
2
3
4
5
6
7
8
9
Description
Size of this descriptor
CS_INTERFACE
OUTPUT_TERMINAL subtype
ID of this terminal
USB Streamer
ID of associate Input Terminal is 0x01
From Feature Unit
Unused
Feature Unit descriptor
Field
bLength
bDescriptorType
bDescriptorSubtype
bUnitID
bSourceID
bControlSize
Size
1
1
1
1
1
1
Value
0x0A
0x24
0x06
0x03
0x01
0x01
bmaControls(0)
1
0x01
bmaControls(1)
1
0x02
bmaControls(2)
1
0x02
iFeature
1
0x00
Note that there is never endpoint descriptor for endpoint 0.
MS0103-E-00
MS0103-E-00
Description
Size of this descriptor
CS_INTERFACE
FEATURE_UNIT descriptor subtype
ID of this feature Unit
ID to Terminal to which this is connected.
Size in bytes of an element of the
bmaControl()
D0(Mute) is enable for Channel 0
D1(Volume) is enable for ch 1(Left)
D1(Volume) is enable for ch 2 (Right)
Unused
2001/06
16
ASAHI KASEI
[AK5371]
3.4 Audio streaming interface
3.4.1
Offset
0
1
2
3
4
5
6
7
8
Zero bandwidth interface descriptor
Field
Size
Value
bLength
1
0x09
bDescriptorType
1
0x04
bInterfaceNumber
1
0x01
bAlternateSetting
1
0x00
bNumEndpoints
1
0x00
bInterfaceClass
1
0x01
bInterfaceSubclass
1
0x02
bInterfaceProtocol
1
0x00
iInterface
1
0x00
Description
Length of this descriptor
INTERFACE descriptor
Index of this interface
Index of this setting
Endpoints 0
AUDIO
AUDIO_STREAMING
Unused
null string
3.4.2
Offset
0
1
2
3
4
5
6
7
8
Interfacedescriptor( Alt = 1, 16bit Mono)
Field
Size
Value
bLength
1
0x09
bDescriptorType
1
0x04
bInterfaceNumber
1
0x01
bAlternateSetting
1
0x01
bNumEndpoints
1
0x01
bInterfaceClass
1
0x01
bInterfaceSubclass
1
0x02
bInterfaceProtocol
1
0x00
iInterface
1
0x00
Description
Length of this descriptor
INTERFACE descriptor
Index of this interface
Index of this setting
Endpoint 1
AUDIO
AUDIO_STREAMING
Unused
null string
3.4.3
Offset
0
1
2
3
4
5
Class-specific audio streaming interface descriptor
Field
Size
Value
Description
bLength
1
0x07
Length of this descriptor
bDescriptorType
1
0x24
CS_INTERFACE descriptor
bDescriptorSubtype
1
0x01
AS_GENERAL
bTerminalLink
1
0x02
Unit ID of terminal(Output Terminal ID)
bDelay
1
0x01
Interface delay
wFormatTag
2
0x0001
PCM
3.4.4
Offset
0
Type I format type descriptor
Field
Size
Value
blength
1
0x17
1
2
3
4
5
6
7
8
11
14
17
20
bDescriptorType
bdescriptorSubtype
bformatType
bNrChannels
bSubFrameSize
bBitResolution
bSamFreqType
tSamFreq[0]
tSamFreq[1]
tSamFreq[2]
tSamFreq[3]
tSamFreq[4]
MS0103-E-00
MS0103-E-00
1
1
1
1
1
1
1
3
3
3
3
3
Description
Size of this descriptor
0x24
0x02
0x01
0x01
0x02
0x10
0x05
0x001F40
0x002B11
0x005622
0x00AC44
0x00BB80
CS_INTERFACE
FORMAT_TYPE
FORMAT_TYPE_I
One channel
Two bytes per slot
16 bits
Five frequencies
8000Hz
11025Hz
22050Hz
44100Hz
48000Hz
2001/06
17
ASAHI KASEI
[AK5371]
3.5 Endpoint descriptor
3.5.1
Offset
0
1
2
3
4
6
7
8
Standard Endpoint Descriptor
Field
Size
Value
bLength
1
0x09
bDescriptorType
1
0x05
bendpointAddress
1
0x81
bmAttributes
1
0x05
wMaxPacketSize
2
0x0064
wInterval
1
0x01
bRefresh
1
0x00
bSynchAddress
1
0x00
3.5.2
Offset
0
1
2
3
4
5
Class-specificisochronous audio data endpoint descriptor
Field
Size
Value
Description
bLength
1
0x07
Size of this descriptor
bDescriptorType
1
0x25
CS_ENDPOINT
bDescriptorSubtype
1
0x01
GENERAL
bmAttributes
1
0x01
Sample rate control
bLockDelayUnits
1
0x00
Unused
wLockDelay
2
0x0000
MS0103-E-00
MS0103-E-00
Description
Length of this descriptor
ENDPOINT descriptor
Endpoint 1, IN direction
Isochronous, asynchronous, not shared
2byte*50sample*1ch=100 byte/frame
One packet every frame (Must be set to 1)
2001/06
18
ASAHI KASEI
[AK5371]
3.5.3
Offset
0
1
2
3
4
5
6
7
8
Interface descriptor(Alt = 2, 16bit Stereo)
Field
Size
Value
bLength
1
0x09
bDescriptorType
1
0x04
bInterfaceNumber
1
0x01
bAlternateSetting
1
0x02
bNumEndpoints
1
0x01
bInterfaceClass
1
0x01
bInterfaceSubclass
1
0x02
bInterfaceProtocol
1
0x00
iInterface
1
0x00
3.5.4
Offset
0
1
2
3
4
5
Class-specific audio streaming interface descriptor
Field
Size
Value
Description
bLength
1
0x07
Length of this descriptor
bDescriptorType
1
0x24
CS_INTERFACE descriptor
bDescriptorSubtype
1
0x01
AS_GENERAL
bTerminalLink
1
0x02
Unit ID of terminal(Output Terminal ID)
bDelay
1
0x01
Interface delay
wFormatTag
2
0x0001
PCM
3.5.5
Offset
0
Type I format type descriptor
Field
Size
Value
blength
1
0x17
1
2
3
4
5
6
7
8
11
14
17
20
bDescriptorType
bdescriptorSubtype
bformatType
bNrChannels
bSubFrameSize
bBitResolution
bSamFreqType
tSamFreq[0]
tSamFreq[1]
tSamFreq[2]
tSamFreq[3]
tSamFreq[4]
MS0103-E-00
MS0103-E-00
1
1
1
1
1
1
1
3
3
3
3
3
Description
Length of this descriptor
INTERFACE descriptor
Index of this interface
Index of this setting
Endpoint 1
AUDIO
AUDIO_STREAMING
Unused
null string
Description
Size of this descriptor
0x24
0x02
0x01
0x02
0x02
0x10
0x05
0x001F40
0x002B11
0x005622
0x00AC44
0x00BB80
CS_INTERFACE
FORMAT_TYPE
FORMAT_TYPE_I
Two channel
Two bytes per slot
16 bits
Five frequencies
8000Hz
11025Hz
22050Hz
44100Hz
48000Hz
2001/06
19
ASAHI KASEI
[AK5371]
3.6 Endpoint descriptor
3.6.1
Offset
0
1
2
3
4
6
7
8
Standard Endpoint Descriptor
Field
Size
Value
bLength
1
0x09
bDescriptorType
1
0x05
bendpointAddress
1
0x81
bmAttributes
1
0x05
wMaxPacketSize
2
0x00C8
wInterval
1
0x01
bRefresh
1
0x00
bSynchAddress
1
0x00
3.6.2
Offset
0
1
2
3
4
5
Class-specificisochronous audio data endpoint descriptor
Field
Size
Value
Description
bLength
1
0x07
Size of this descriptor
bDescriptorType
1
0x25
CS_ENDPOINT
bDescriptorSubtype
1
0x01
GENERAL
bmAttributes
1
0x01
Sample rate control
bLockDelayUnits
1
0x00
Unused
wLockDelay
2
0x0000
MS0103-E-00
MS0103-E-00
Description
Length of this descriptor
ENDPOINT descriptor
Endpoint 1, IN direction
Isochronous, asynchronous, not shared
2byte*50sample*2ch=200 byte/frame
One packet every frame (Must be set to 1)
2001/06
20
ASAHI KASEI
[AK5371]
3.7 String descriptor 1
String descriptors use UNICODE. except for LANGID.
3.7.1
Offset
0
1
2
LANGID (0 x00) Field
Field
bLength
bDescriptorType
bString
3.7.2
Offset
0
1
2
iManufacterer 0x01)
(
Field in Device Descriptor
Field
Size
Value
Description
bLength
1
0x34
Length of this descriptor
bdescriptorType
1
0x03
STRING descriptor
“AKM
”
bString
50
0x0041
0x004B
0x004D
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
MS0103-E-00
MS0103-E-00
Size
1
1
2
Value
0x04
0x03
0x0409
Description
Length of this descriptor
STRING descriptor
“English(US)”
2001/06
21
ASAHI KASEI
3.7.3
Offset
0
1
2
iProduct (0x02) Field in Device
Descriptor
Field
Size
Value
bLength
1
0x34
bDescriptorType
1
0x03
bString
50
0x0041
0x004B
0x0035
0x0033
0x0037
0x0031
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
0x0020
MS0103-E-00
MS0103-E-00
[AK5371]
Description
Length of this descriptor
STRING descriptor
“AK5371
”
2001/06
22
ASAHI KASEI
[AK5371]
4 Standard requests
4.1 Clear Feature
The AK5371 accepts “Clear Feature” request without stall. Though this request does not influence to the
operation of the device, the AK5371 does not support this request.
4.2 Get Configuration
The AK5371 returns Configuration value.
Field
Size
Value
Offset
0
bmRequestType
1
0x80
1
bRequest
1
0x08
2
wValue
2
0x0000
4
wIndex
2
0x0000
6
wLength
2
0x0001
Description
GET_CONFIGURATION
AKM USB Mic. has one configuration.
4.3 Get Descriptor
Offset
0
1
2
Field
bmRequestType
bRequest
wValue
Size
1
1
2
Value
0x80
0x06
0xZZZZ
4
wIndex
2
0x0000
6
wLength
2
0xZZZZ
Description
GET_DESCRIPTOR
ZZZZ is assigned by host:
High Byte is Descriptor Type, Low Byte is Index.
DEVICE : 0x0100 : (Index is 0 only)
CONFIGURATION : 0x0200
STRING: 0x03??(?? is 00, 01, 02)
if wValue is DEVICE or CONFIGURATION, wIndex is
zero. If wValue is 0x0300(LANGID), wIndex is zero.
If wValue is 0x0301 or 0x0302, wIndex is
0x0409“English(US)”.
Descriptor Length (ZZZZ is assigned by host)
4.4 Get Interface
The AK5371 returns the current bAlternateSetting value.
Offset Field
Size
Value
Description
0
bmRequestType
1
0x81
1
bRequest
1
0x0A
GET_INTERFACE
2
wValue
2
0x0000
ZERO
4
wIndex
2
0x0000
Audio Control Interface
0x0001
Audio Streaming Interface
6
wLength
2
0x0001
AKM USB Mic. Has zero bandwidth Audio
Streaming Interface and normal Audio Streaming
Interface.
MS0103-E-00
MS0103-E-00
2001/06
23
ASAHI KASEI
[AK5371]
4.5 Get Status
Offset
0
Field
bmRequestType
1
2
4
6
bRequest
wValue
wIndex
wLength
Size
1
1
2
2
2
Value
0x80
0x81
0x82
0x00
0x0000
Description
DEVICE
INTERFACE
ENDPOINT
GET_STATUS
ZERO
0x0002
The AKM USB MIC returns the following status.
a)Device : 0x00 ( AKM USB MIC is bus-powered device)
b)Interface: 0x00 (All Zero)
c)Endpoint : 0x00
4.6 Set Address
AKM USB MIC stores the wValue in the internal memory as Device Address. In addition to this, the device
returns ACK.
Offset Field
Size
Value
Description
0
bmRequestType
1
0x00
Zero
1
bRequest
1
0x05
SET_ADDRESS
2
wValue
2
0xZZZZ
Device Address : ZZZZ is assigned by host
4
wIndex
2
0x0000
Zero
6
wLength
2
0x0000
Zero
4.7 Set Configuration
AKM USB MIC is placed to configured state only wValue of this request is 0x0001. In addition to this, the device
returns ACK.
Offset Field
Size
Value
Description
0
bmRequestType
1
0x00
Zero
1
bRequest
1
0x09
SET_CONFIGURATION
2
wValue
2
0x0000
Unconfigured State
0x0001
AKM USB MIC is set to configured state
others
Invalid
4
wIndex
2
0x0000
Zero
6
wLength
2
0x0000
Zero
MS0103-E-00
MS0103-E-00
2001/06
24
ASAHI KASEI
[AK5371]
4.8 Set Feature
The AK5371 accepts “Set Feature” request without stall. However note that the AK5371 does not support this
request.
4.9 Set Interface
Audio format can be changed by the combination of Interface Number and Alternate Setting. Only 0x0000 is valid
if wIndex is 0x0000
Offset Field
Size
Value
Description
0
bmRequestType
1
0x01
ONE
D7
0 = Host to device
D6..5 0 = Standard request
D4..0 1 = Recipient is interface
1
bRequest
1
0x0B
SET_INTERFACE
2
wValue
2
Alternate Setting
0x0000
Control Interface or Zero Bandwidth
0x0001
16bit Mono
0x0002
16bit Stereo
4
wIndex
2
0x0000
Audio Control Interface
0x0001
Audio Streaming Interface
6
wLength
2
0x0000
Zero
MS0103-E-00
MS0103-E-00
2001/06
25
ASAHI KASEI
[AK5371]
5 Device specificRequests
AKM USB Microphone supports ONLY SET_CUR as bRequest field in Set Request Values.
5.1 Audio Control Request
AKM USB microphone support ONLY Feature Unit Control Request, not support other requests. Addition to this,
it only supports SET_CUR value as bRequest field in Set Feature Unit Control Request Values. All Audio Control
Requests are applied to channel 0,1,2, which means master , left and right channel.
5.1.1
Set Feature Unit Control Request
AKM USB Microphone supports only one form of parameter block. Mute control is applied to master channel
(channel 0)
a) Mute Control
Offset Field
Size
Value
Description
0
bmRequestType
1
0x21
1
bRequest
1
0x01
SET_CUR
2
wValue
2
0x0100
MUTE_CONTROL | CHANNEL_0
4
wIndex
2
0x0300
Upper Byte : bUnit ID field in Feature Unit
Descriptor.(0x03)
Lower Byte : Audio Control Interface(0x00)
6
wLength
2
0x0001
The Length of Mute Control Parameter Block
The parameter block of mute control is the following.
Offset Field
Size
Value
Description
0
bMute
1
0x01
TRUE
0x00
FALSE
a) Volume Control
Left (channel 1) volume and right (channel 2) volume are controlled independently.
Offset Field
Size
Value
Description
0
bmRequestType
1
0x21
1
bRequest
1
0x01
SET_CUR
2
wValue
2
0x0201
VOLUME_CONTROL | CHANNEL_1
0x0202
VOLUME_CONTROL | CHANNEL_2
4
wIndex
2
0x0300
Upper Byte : bUnit ID field in Feature Unit
Descriptor.(0x03)
Lower Byte : Audio Control Interface(0x00)
6
wLength
2
0x0002
Volume Control
The parameter block of mute control is the following.
Offset Field
Size
Value
Description
0
wVolume
2
0xZZZZ
The value is mapped to the volume register value.
(refer to Table 1 conversion table )
ZZZZ is assigned by the host
If the wVolume exceeds the range, the AK5371 forces the value into the range. Please see the conversion table in
the Get Feature Unit Control Request.
MS0103-E-00
MS0103-E-00
2001/06
26
ASAHI KASEI
[AK5371]
5.1.2
Get Feature Unit Control Request
AKM USB Microphone supports only one form of parameter block.
a) Mute Control
Offset Field
Size
Value
Description
0
bmRequestType
1
0xA1
1
bRequest
1
0x81
GET_CUR
2
wValue
2
0x0100
MUTE_CONTROL | CHANNEL_0
4
wIndex
2
0x0300
Upper Byte : bUnit ID field in Feature Unit
Descriptor.(0x03)
Lower Byte : Audio Control Interface(0x00)
6
wLength
2
0x0001
The Length of Mute Control Parameter Block
The device outputs the current setting of mute status.
Offset Field
Size
Value
Description
0
bMute
1
0x01
TRUE
0x00
FALSE
b) Volume Control
Offset Field
0
bmRequestType
1
bRequest
Size
1
1
2
wValue
2
4
wIndex
2
Value
0xA1
0x81
0x82
0x83
0x84
0x0201
0x0202
0x0300
6
wLength
2
0x0002
Description
GET_CUR
GET_MIN
GET_MAX
GET_RES
VOLUME_CONTROL | CHANNEL_1
VOLUME_CONTROL | CHANNEL_2
Upper Byte : bUnit ID field in Feature Unit
Descriptor.(0x03)
Lower Byte : Audio Control Interface(0x00)
Volume Control
The parameter block of Volume Control is the following.
Offset Field
Size
Value
Description
0
wVolume
2
0xZZYY
bRequest = GET_CUR : returns current volume.
YY must be 00h
0xE100
bRequest = GET_MIN : -31dB
0x1800
bRequest = GET_MAX : +24dB
0x0100
bRequest = GET_RES : 1.0dB
Table 1 is the conversion map of USB class and internal volume register.
When host requests the volume value which is larger than the MAX value in the device, the device is set the MAX
value to the volume. When host requests the volume value which is smaller than the MIN value in the device, the
device is set the MIN value to the volume. RES value is 1.0dB.
MS0103-E-00
MS0103-E-00
2001/06
27
ASAHI KASEI
[AK5371]
Field
wVolume
0x7FFF
-------0x1800
0x17FF
--------0x1701
0x1700
0x16FF
--------0x1201
0x1200
----------------0x02FF
--------0x0201
0x0200
0x01FF
--------0x0101
0x0100
0x00FF
--------0x0001
0x0000
0xFFFF
-------0xFF01
0xFF00
0xFEFF
-------0xFE01
0xFE00
----------------0xE200
0xE1FF
--------0xE101
0xE100
0xE1FF
--------0x8000
Internal
Value
0x1800
-----0x1800
0x1700
-----0x1700
0x1700
0x1600
-----0x1200
0x1200
----------------0x0200
--------0x0200
0x0200
0x0100
--------0x0100
0x0100
0x0000
--------0x0000
0x0000
0xFF00
-------0xFF00
0xFF00
0xFE00
-------0xFE00
0xFE00
----------------0xE200
0xE100
--------0xE100
0xE100
0xE100
0xE100
value
24.0000
--------24.0000
23.0000
-------23.0000
23.0000
22.0000
-------18.0000
18.0000
--------------2.0000
-------2.0000
2.0000
1.0000
--------1.0000
1.0000
0.0000
--------0.0000
0.0000
-1.0000
--------1.0000
-1.0000
-2.0000
--------2.0000
-2.0000
-----------------30.0000
-31.0000
---------31.0000
-31.0000
-31.0000
---------31.0000
Step
1.0dB
Table 1 Conversion Table of Volume Control
MS0103-E-00
MS0103-E-00
2001/06
28
ASAHI KASEI
[AK5371]
5.2 Endpoint Control Request
The AK5371 supports five sampling frequencies. The sampling rate is changed when “Set Endpoint
Control Request ” is issued. SET_CUR, GET_CUR of bRequest is only supported. GET_MIN, GET_
MAX, and GET_RES of bRequest are not supported.
5.2.1
Set Endpoint Control Request
Offset
0
1
2
Field
bmRequestType
bRequest
wValue
Size
1
1
2
Value
0x22
0x01
0x0100
4
wIndex
2
0x0081
6
wLength
2
0x0003
Description
SET_CUR
Upper byte: SAMPLING_FREQ_CONTROL (0x01)
Lower byte : zero
Upper Byte : zero
Lower Byte : Endpoint Address (0x81)
The Length of Sampling Frequency Parameter
Block
The parameter block of mute control is the following.
Offset Field
Size
Value
Description
0
iSampleFreq
3
0xYYYYYY
The following five values are valid. Others are
invalid.
0x001F40 : 8kHz
0x002B11 : 11.025kHz
0x005622 : 22.05kHz
0x00AC44 : 44.1kHz(default)
0x00BB80 : 48kHz
If the iSampleFreq is different from the above values, the AK5371 forces sampling frequency to the
appropriate value.
5.2.2
Get Endpoint Control Request
Offset
0
1
2
Field
bmRequestType
bRequest
wValue
Size
1
1
2
Value
0xA2
0x81
0x0100
4
wIndex
2
0x0081
6
wLength
2
0x0003
Description
GET_CUR
Upper byte: SAMPLING_FREQ_CONTROL (0x01)
Lower byte : zero
Upper Byte : zero
Lower Byte : Endpoint Address (0x81)
The Length of Sampling Frequency Parameter
Block
The parameter block of mute control is the following.
Offset Field
Size
Value
Description
0
iSampleFreq
3
0xYYYYYY
The following five values are valid.
invalid.
0x001F40 : 8kHz
0x002B11 : 11.025kHz
0x005622 : 22.05kHz
0x00AC44 : 44.1kHz
0x00BB80 : 48kHz
MS0103-E-00
MS0103-E-00
Others are
2001/06
29
ASAHI KASEI
[AK5371]
Package
48pin LQFP(Unit:mm)
1.70Max
9.0 ± 0.2
0.10 ± 0.07
7.0
36
1.4TYP
25
48
9.0 ± 0.2
24
7.0
37
13
1
12
0.17 ± 0.05
0.5
0.19 ± 0.05
0.10 M
0° ∼ 10°
0.10
MS0103-E-00
MS0103-E-00
0.5 ± 0.2
2001/06
30
ASAHI KASEI
[AK5371]
Marking
AK5371VQ
XXXXXXX
1
1) Pin #1 indication
2) Date Code: XXXXXXX (7 digits)
3) Marking Code: AK5371VQ
4) Asahi Kasei Logo
MS0103-E-00
MS0103-E-00
2001/06
31
ASAHI KASEI
[AK5371]
IMPORTANT NOTICE
• These products and their specifications are subject to change without notice. Before
considering any use or application, consult the Asahi Kasei Microsystems Co., Ltd. (AKM) sales
office or authorized distributor concerning their current status.
• AKM assumes no liability for infringement of any patent, intellectual property, or other right in the
application or use of any information contained herein.
• Any export of these products, or devices or systems containing them, may require an export
license or other official approval under the law and regulations of the country of export pertaining
to customs and tariffs, currency exchange, or strategic materials.
• AKM products are neither intended nor authorized for use as critical components in any safety,
life support, or other hazard related device or system, and AKM assumes no responsibility
relating to any such use, except with the express written consent of the Representative Director
of AKM. As used here:
(a) A hazard related device or system is one designed or intended for life support or
maintenance of safety or for applications in medicine, aerospace, nuclear energy, or other
fields, in which its failure to function or perform may reasonably be expected to result in loss
of life or in significant injury or damage to person or property.
(b)A critical component is one whose failure to function or perform may reasonably be expected
to result, whether directly or indirectly, in the loss of the safety or effectiveness of the device
or system containing it, and which must therefore meet very high standards of performance
and reliability.
• It is the responsibility of the buyer or distributor of an AKM product who distributes, disposes of,
or otherwise places the product with a third party to notify that party in advance of the above
content and conditions, and the buyer or distributor agrees to assume any and all responsibility
and liability for and hold AKM harmless from any and all claims arising from the use of said
product in the absence of such notification.
MS0103-E-00
MS0103-E-00
2001/06
32
Similar pages