1
A
SAHI KASEI
MS0103-E-00
MS0546-E-00
[AK5371
A
]
2007
/
02
Features:
USB-IF Certified
Incorporates USB Audio Controller
USB Serial Interface Engine
Audio Class Encoder/Decoder
2 Endpoints (FIFO)
USB transcei ver
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
EEPROM I/F
can customize Device Descriptor,
and String Descriptor
Single Power Supply, Low Power
+3.3±0.3 Volts
Package
48pin LQFP
General Description
The AK5371A is stereo A/D converter with USB I/F. The
AK5371A integrates USB serial interface engine, USB
transceiver, audio class processing unit, endpoints, and high
quality 2 channel AD converter into the chip.
As the AK5371A incorporates PLL, it can support several
sampling frequencies, 8kHz, 11.025kHz, 22.05kHz, 44.1kHz,
and 48kHz with only one crystal. Moreover, the AKAK5371A
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 AK5371A includes 20dB fixed gain pre-amplifier. In
addition to this, as the AK5371A also incorporates IPGA
which can amplify the microphone signal up to +24dB, total
gain is 44dB maximum.
The AK5371A has EEPROM I/F for customizing Device
Descriptor and String Descriptor. By connecting 1K bit, 2K
bit, or 4Kbit MicrowireTM type EEPROM, the AK5371A 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.
Related Documents
For the detail of USB specification, and Audio Class, please
refer to the following documents.
Universal Serial Bus Specification Revision 1.1
Universal Serial Bus Device Class Definition for Audio
Devices, Revision 1.0
AK5371A 2ch A/D Converter with USB I/F
2
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
Block Diagram
Ordering Guide
AK5371AVQ 0 ∼ +70 °C 48pin LQFP (0.5mm pitch)
AKD5371 Evaluation Board
Pin Layout
XTALOUT
VD
VSS1
VSS2
NC
TESTMODE3
TESTMODE2
XTALIN
LFLT1
LFLT2
BIASSEL
NC
1
10
20
30
40
5
15 25
35
45
NC
NC
VCOM
MICL
AMPL1O
AMPL2I
AMPL2O
MICR
AMPR1O
AMPR2I
AMPR2O
NC
EPAO
SK
CS
TEST
NC
TESTMODE1
NC
VREF
VSS3
VA
NC
NC
DN
DP
NC
NC
RSTN
SUSN
NC
EPSEL
EPEN
EPDI
NC
MICBIAS
MICL
V
A
LFLT1
EndPoint1
IN_FIFO
V
SS3
V
D
16bit
ADC
V
SS1
DN
DP
Mute
&
V
olume
control
EndPoint0
IN_FIFO
EndPoint0
OUT_FIFO
Audio Class
Decoder
Audio Class
Encoder Serial
Interface
Engine
XTLIN XTLOUT
V
COM
USB
Transceiver
PLL
adCLK
SystemCL
K
CRYSTAL
AMPR2O
-
+
MICBIAS
RSTN
C
on
f
ig/
S
tring
ROM
Testmode1,2,3
TEST
LFLT2
V
REF
MICR
-
+
-
+
-
+
AMPL2O
CS
SK
EPAO
EPDI
AMPR1O
AMPR2I
AMPL1O
AMPL2I
20dB
20dB
EEPROM
Control
microwir
e
EEPROM
(1K bit)
EPEN
SUSN
EPSEL
V
REF
BIASSEL
Common Voltage
V
SS2
3
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
Pin/Function
No. Signal Name I/O Ana / Dig Description
1 VD P D Digital Power Supply, 3.3V
2 VSS1 P D Digital Ground,0V
3 VSS2 P D Bulk Ground, 0V
4 NC - - No Connection
5 TESTMODE3 I D Please tie down to VSS3 for normal operation.
6 XTALOUT O A Crystal Oscillator Output, Connect Crystal Resonator
7 XTALIN I A Crystal Oscillator Input, Connect Crystal Resonator
8 TESTMODE2 I A Please tie down to VSS3 for normal operation.
9 LFLT1 O A adPLL loop filter Pin. Connect 51kΩ resistor and 8200pF
capacitor in series externally.
10 LFLT2 O
A System clock PLL loop filter Pin. Connect 18kΩ resistor and
6800pF capacitor in series externally.
11 BIASSEL I D MIC BIAS Select Pin
Select MICBIAS Output
"L": VA(through switch)
“H”: VREF buffer output
12 NC - - No Connection
13 NC - - No Connection
14 VCOM O A Analog Common Voltage Reference Pin
15 MICBIAS O A Voltage Reference Output for the Microphone’s bias voltage
When this chip goes into Suspend mode, this pin goes to Hi-Z.
16 MICL I A Left Channel Microphone Input
17 AMPL1O O A Left Channel 1st Amplifier Output Pin
18 AMPL2I I A Left Channel 2nd Amplifier Input Pin
19 AMPL2O O A Left Channel 2nd Amplifier Output Pin
20 NC - - No Connection
21 MICR I A Right Channel Microphone Input
22 AMPR1O O A Right Channel 1st Amplifier Output Pin
23 AMPR2I I A Right Channel 2nd Amplifier Input Pin
24 AMPR2O O A Right Channel 2nd Amplifier Output Pin
4
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
No. Signal Name I/O Ana / Dig Description
25 NC - - No Connection
26 VA P A Analog Power Supply, 3.3V
27 VSS3 P A Analog Ground,0V
28 VREF O A ADC Common Voltage Reference Pin.
29 NC - - No Connection
30 TESTMODE1 I A Please tie down to VSS3 for normal operation.
31 NC - - No Connection
32 TEST I/O D Please tie down to VSS3 for normal operation.
33 CS O D EEPROM I/F Chip Select Pin
34 SK O D Serial Clock Pin
35 EPAO O D EEPROM Address Output Pin
36 NC - - No Connection
37 NC - - No Connection
38 EPDI I D EEPROM Data Input Pin (This pin is internally pulled down)
39 EPEN I 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”
40 EPSEL I D 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 VSS1.
41 NC - - No Connection
42 SUSN O D Suspend Status Pin
"L" : Suspend State
"H" : Normal Operation
43 RSTN I D Reset Pin, Low input makes the chip reset sate.
Schmitt Trigger input.
44 NC - - No Connection
45 NC - - No Connection
46 DP I/O D USB bus Non-Inverting pin.
Because AK5371A is full speed mode device, 1.5kΩ resistor will
be connected between D+ node to VD.
47 DN I/O D USB bus Inverting Pin.
48 NC - - No Connection
5
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
Absolute Maximum Rating
VSS1=VSS2=VSS3=0V
Parameter Symbol Min Max Units
Power Supplies
Analog
Digital
VSS3
VSS1
-0.3
-0.3
4.5
4.5
V
V
Input Current (any pins except for supplies) IIN - ±10 mA
Analog Input Voltage VINA -0.3 VA+0.3 V
Digital Input Voltage VIND -0.3 VD+0.3 V
Ambient Temperature Ta 0 70 °C
Storage Temperature Tstg -40 125 °C
Note 1. All voltages with respect to ground. VSS1, VSS2 and VSS3 pin should be connected.
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
VSS1=VSS2=VSS3=0V
Parameter Symbol Min typ Max Units
Power Supplies
Analog
Digital
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.
6
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
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)
(IPGA are set to 0dB) USB Normal Mode
84 dBA
S/(N+D) (-1dB analog input)
(IPGA are set to 0dB) USB Normal Mode
70 dB
MIC Amplifier (2nd 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
MIC Amplifier (1st 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
Digital
Total
Power Down (Suspend Mode)
17
9
26
0
25
15
40
160
mA
mA
mA
uA
FILTER CHARACTERISTICS
(Ta=25°C VA, VD =3.0 - 3.6 V ; fs = 44.1 kHz)
Parameter Symbol Min typ Max Units
A/D Digital Filter
(Decimation LPF)
Passband +/- 0.2 dB PB 0 17.64 KHz
Stopband SB 26.5 KHz
Passband Ripple PR +/- 0.2 dB
Stopband Attenuation SA 68 dB
Group Delay GD 0.5 ms
A/Ddigital Filter (HPF)
Frequency Response -3 dB
-0.5 dB
-0.1 dB
FR 6.85
19.2
44.9
Hz
Hz
Hz
7
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
Digital DC Characteristics
Ta=0 - 70°C; VD=3.0 - 3.6V; VSS1=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 Symbol Min Typ Max Units
EPDI, EPEN, EPSEL, pin “H” level input voltage VIH 70%VD V
EPDI, EPEN, EPSEL pin “L” level input voltage VIL 30%VD V
RSTN pin “H” level voltage VIHR 2.0 V
RSTN pin “L” level voltage VILR 0.8 V
CS, SK, EPAO, SUSN pin “H” level output
voltage IOH = 2mA
VOH 2.4 V
CS, SK, EPAO, SUSN pin “L” level output
voltage IOL = -2mA
VOL 0.6 V
Input Leakage Current Iin ±10 μA
Switching Characteristics
Ta=25°C, VA=VD=3.3V
Parameter Symbol Min Typ Max Units
Master Clock Frequency MCLK - 11.2896 - MHz
Reset input width @RSTN pin(low active) Wrst 1.0 us
DP,DN Single Ended Receiver Threshold
for H level
for L level
VseH
VseL
2.0
0.8
V
Time Width for USB Reset Signal Recognition*1
DP<VseL & DN< VseL to USB Reset mode Trst_rec 2.7
μs
Device Ready Time from USB Reset
Ready for transaction after reset Tdrr 10 ms
Time Width for Suspend Recognition
Idle state ( DP > VseL & DN < VseL )
to Suspend mode
Tsus_rec 3.0 ms
Resume Time from Suspend
First flip of DP/DN from Idle sate
To Device Ready*)
Tresm 30 ms
Device Ready: VREF, X’tal oscillator, and PLL get stable and bus transaction with normal rate is ready.
Reset Mode
PLL
Clock
DN
DP
VD
Device
Connected
RSTN
Tdrr
min 20ms
Resume
min 10ms
resume time resume recovery time
Trst_rec
Figure 1. Mode change with respect to BUS States 1 (Power on and device connected)
8
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
PLL
Clock
D-
D+
VD”H”
Tresm
Tsus_rec
RST”H”
Figure 2. Mode Change with respect to Bus States 2 (Bus transactions)
Transmitter Characteristics
Ta=25°C; VD=3.3V; VSS1=0V; CL=50pF
Parameter Symbol Pins Conditions Min Typ Max Units
Data Rate DR DP,DN 11.97 12 12.03 MHz
Output Impedance (Hi) Roh DP, DN DP, DN=”H”
at Iout = -10mA 36 Ω
Output Impedance (Lo) Rol DP, DP DP, DN=”L”
at Iout = 10mA 36 Ω
“H” level Output Voltage Vohd DP, DN at Iout =-200uA 2.8 V
“L” level Output Voltage Vold DP, DN at Iout =2.2mA 0.3 V
Tri-state Leakage Current Iolk DP, DN 0 < DP, DN< 3.3V -10 10 μA
Rise/Fall Time Trf/Tff DP, DN 4 10 20 ns
Rise/Fall Time Matching Trfm DP, DN 100 %
Crossover Point Vcrs DP, DN 1.65 V
10%VD
90%VD
Trs
Trf
DP, DN
Tfs
Tff
Figure 3. Rise/Fall Time
V
crs
DP, DN
Figure 4. Crossover Point
9
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
Receiver Characteristics
Ta=25°C; VD=3.3V; VSS1=0V
Parameter Symbol Pins Conditions Min Typ Max Units
Common Mode Range CMR DP, DN 0.8 V
Differential Input Sensitivity DIS DP, DN 200 mV
Schmitt High Level Voltage Vihs DP, DN 2.0 V
Schmitt Low Level Voltage Vils DP, DN 0.8 V
V
ils
V
ihs
DP, DN
Figure 5. Schmitt Level Voltage
10
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
Overview of AK5371 A
The AK5371A is the advanced stereo A/D converter, which converts an alog signal into USB audio class formats. As the AK5371A
incorporates all functions to build USB Audio Input Device, the AK5371A doesn’t require additional micro-controller, memor y, and
a transceiver. Moreover, as the AK5371A 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 AK5371A, one crystal, one regulator, and microphone
unit(s). As the AK5371A also has EEPROM interface, descriptors can be customized easily. The AK5371A 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) 11.2896MHz crystal
b) 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 AK5371A supports 5 sampling frequencies (8kHz, 11.025kHz, 22.05kHz, 44.1kHz, 48kHz). In order to support these
frequencies, the AK5371A 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 AK5371A 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 rec eiving the resume signal. Th e AK5371A notifies the
current state (normal state or suspend state) by SUS_N pin.
As the AK5371A has Microwire™ EEPROM I/F, the vendors can customize iManifacterer, iProduct, and the related strings to
their own ID, and string.
11
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
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02
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 defau lt pipe (Endpoint 0) . The AK 5371A consists of one Device Descriptor, one
Configuration Descriptor, two Interface Descriptors, and two Endpoint Descriptors.
Figure 6 shows Descriptor’s hierarchy.
Configuration
Descriptor
Device
Descriptor
Standard Audio Control
Interface Descriptor
Class-Specific Audio Control
Interface Descriptor
Standard AS Interface
Descriptor Alt. Setting 0
Class-Specific AS Format Type
Descriptor
Standard AS Isochronous
Endpoint Descriptor
Class-Specific AS Isoch ronous
Endpoint Descriptor
Standard AS Interface
Descriptor Alt. Setting 1
Class-Specific Audio Streaming
Interface Descriptor
StandardInterface Descriptor
Class-Specific Descriptor
C
on
fig
urat
i
on
D
ev
i
ce
Class-Specific AS Format Type
Descriptor
Standard AS Isochronou s
Endpoint Descriptor
Class-Specific AS Isochronous
Endpoint Descriptor
Standard AS Interface
Descriptor Alt. Setting 2
Class-Specific Audio Streaming
Interface Descrip tor
E
n
d
po
i
n
t
(IN)
I
nter
f
ace
0
I
nter
f
ace
1
Figure 6. Descriptor Hierarchy
12
MS0103-E-00
MS0546-E-00
A
SAHI KASEI [AK5371
A
]
2007
/
02
Audio Format of the AK5371A
The AK5371A supports two audio formats: 16bit/mono and 16bit/stereo. This feature ca n avoid the unnecessary occupation of USB
bandwidth. 16bit/mono is assigned to <Interlace 1, Alt1>, 16bit/stereo is assigned to <Interf ace 1, Alt2>. The A/D data on USB bus
is LSB first, Left channel first. When 16bit/mono audio format is selected, the AK5371A outputs left channel data on the USB bus.
Audio format is changed by “Set Interface” Request.
Synchronization
The AK5371A operates as Asynchronous Device. A/D converter in the AK5371A operates as ynchronously with USB SOF timing.
The data from A/D converter are s ent continuously to a buffer memory while the data are burstly transf erred at the interval of SOF on
the USB. In order to arbitrate the differen ce of timing, AK5371A has a FIFO memory with a capacity of 2-frame d epth .The average
sampling rate calculating from USB frame should be in accordance with A/D sampling rate (fs).
The AK5371A 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 frequ ency is set to 44.1kHz, the AK5371A sends 45 samples once per ten times, and sends
44 samples in other frames. Average frequency is 44.1kHz. See Figure 7.
44 samples 44 s a m ples 45 samples
N
Frame (N+1) Frame (N+9) Frame
44 samples
(N+10) Frame
Figure 7. Synchronization
Power Management Control
When idle state continues for 3ms, the AK5371A goes to suspend state and for ces almost all blocks includ ing PLL, ADC block an d
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 AK5371A 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 AK5371A, by also regulator(s), and resistors.
Therefore, low power regulator should be selected to design USB microphone.
Feature Unit Control & Frequency Control
When the AK5371A 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 AK5371A 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 AK5371A 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 AK5371A receives “GET_ENDPOINT_CONTROL”
request, it sends back the current value to the host.
13
MS0103-E-00
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SAHI KASEI [AK5371
A
]
2007
/
02
EEPROM I/F
The AK5371A 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 AK5371A automatically reads Device Descriptor from the EEPROM and stores internal memory after USB reset.
When the AK5371A receives “GET String Descriptor" request, the AK5371A starts reading from EEPROM. The AK5371A
continues to send NAK packet while it is reading String from EEPROM.
Memory mapping of EEPROM is the following.
1K bit
(AK93C45A) 2K/4K bit
(AK93C55A / 65A)
Device Descriptor (18 bytes) 00h - 08h 00h - 08h
String Descriptor Lang ID (4 bytes index = 0) 09h - 0Ah 09h - 0Ah
String Descriptor iManufacturer (52 or 102bytes index =1) 0Bh - 24h 0Bh - 3Dh
String Descriptor iProduct (52 or 102 bytes index = 2) 25h - 3Eh 3Eh - 71h
Note that EEPROM address is 16bit boundary.
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 VSS1.
Device Descriptor and S tring Descriptor should be stored in EEPROM before the A K5371A is powered up. EPEN pi n 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 VSS1. Note that CS pin, SK pin, and EPAO
pin are Hi-Z state when EPEN is “L”. EPDI pin is internally pulled down.
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SAHI KASEI [AK5371
A
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2007
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02
System Block Diagram
The following figure shows the system connection diagram. This is an exam ple which uses ext ernal 1K bit EEPROM (AK93C45A)
as Device and String Descriptor. If EEPROM is not used, EPEN pin should be tied to VSS1.
Ceramic capacitors (0.1uF) for VA pin, VD pin, VREF pin and VCOM pin should be located as near as possible.
1M
Cd Cd
AMP2RO AMP2LO LFLT1
,
2XTALIN
11.2896M
VSS3
RSTN
XTALOUT
MICBIAS
MICR
VREF
Testmode 1
DP
DN
1.5k
D+
D- To Ho st/Hub
C3:1000p
C1:1.0u<
100u
0.1u 0.1u
4.7u
0.1u
4.7u
Regulator
0.1u 10u
10uH
3300p
56k
0.1u
51k
0.1u
4.7u 0.1u 4.7u
Testmode 2
Testmode 3
Test
VCOM VA VSS3 VD VSS1
VSS2
18k
8200p 6800p
C2:0.33u
AMPR1O
AMPR2I
MICL
C1:1.0u<
C2:0.33u
AMPL1O
AMPL2I
C3:1000p
<REMARK> This drawing does NOT mean physical pin locations/ordering
Phone Jack
STEREO SW
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. 330Ω resister when BIASSEL is High
Cd: Please select the appropriate value according to crystal resonator’s characteristics
R1:4.7k
100u
0.1u
R1:4.7k
10Ω
GND
5V
GND
VSS1
10u
CS
SK
EPAO
EPDI
EEPROM
R0
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AK5371A Descriptors Specification
1 Device descriptor
Offset Field Size Value Description
0 bLength 1 0x12 Size of this descriptor in bytes
1 bDescriptorType 1 0x01 DEVICE descriptor
2 bcdUSB 2 0x0110 1.10 – current revision of USB spec.
4 bDeviceClass 1 0x00 Device defined at Interface level
5 bDeviceSubClass 1 0x00 Unused
6 bDeviceProtocol 1 0x00 Unused
7 bMaxPacketSize0 1 0x08 8 bytes
8 idVendor 2 0x0556 AKM’s Vendor ID
10 idProduct 2 0x0002 00 means Audio Product, 02 is AKMproduct ID ,
12 bcdDevice 2 0x0001 Device release code
14 iManufacturer 1 0x01 “AKM”
15 iProduct 1 0x02 “AK5371”
16 iSerialNumber 1 0x00 Unused
17 bNumConfigurations 1 0x01 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.
4 bNumInterfaces 1 0x02 Two interfaces
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
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3.2 Class-specific Audio Control Interface
3.3 Class-specific Audio Control Interface Header Descriptor
3.3.1 Contains general information about the audio device.
Offset Field Size Value Description
0 bLength 1 0x09 Size of this descriptor
1 bDescriptorType 1 0x24 CS_INTERFACE
2 bDescriptorSubtype 1 0x01 HEADER subtype
3 bcdADC 2 0x0100 Revision of class specification – 1.0
5 wTotalLength 2 0x0028 Total size of class-specific Audio Control
Interface descriptors (includes this
descriptor)
7 bInCollection 1 0x01 Number of streaming interfaces
8 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 Description
0 bLength 1 0x09 Size of this descriptor
1 bDescriptorType 1 0x24 CS_INTERFACE
2 bDescriptorSubtype 1 0x03 OUTPUT_TERMINAL subtype
3 bTerminalID 1 0x02 ID of this terminal
4 wTerminalType 2 0x0101 USB Streamer
6 bAssocTerminal 1 0x01 ID of associate Input Terminal is 0x01
7 bSourceID 1 0x03 From Feature Unit
8 iTerminal 1 0x00 Unused
3.3.4 Feature Unit descriptor
Offset Field Size Value Description
0 bLength 1 0x0A Size of this descriptor
1 bDescriptorType 1 0x24 CS_INTERFACE
2 bDescriptorSubtype 1 0x06 FEATURE_UNIT descriptor subtype
3 bUnitID 1 0x03 ID of this feature Unit
4 bSourceID 1 0x01 ID to Terminal to which this is connected.
5 bControlSize 1 0x01 Size in bytes of an element of the
bmaControl()
6 bmaControls(0) 1 0x01 D0(Mute) is enable for Channel 0
7 bmaControls(1) 1 0x02 D1(Volume) is enable for ch 1(Left)
8 bmaControls(2) 1 0x02 D1(Volume) is enable for ch 2 (Right)
9 iFeature 1 0x00 Unused
Note that there is never endpoint descriptor for endpoint 0.
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3.4 Audio streaming interface
3.4.1 Zero bandwidth interface descriptor
Offset Field Size Value Description
0 bLength 1 0x09 Length of this descriptor
1 bDescriptorType 1 0x04 INTERFACE descriptor
2 bInterfaceNumber 1 0x01 Index of this interface
3 bAlternateSetting 1 0x00 Index of this setting
4 bNumEndpoints 1 0x00 Endpoints 0
5 bInterfaceClass 1 0x01 AUDIO
6 bInterfaceSubclass 1 0x02 AUDIO_STREAMING
7 bInterfaceProtocol 1 0x00 Unused
8 iInterface 1 0x00 null string
3.4.2 Interface descriptor(Alt = 1, 16bit Mono)
Offset Field Size Value Description
0 bLength 1 0x09 Length of this descriptor
1 bDescriptorType 1 0x04 INTERFACE descriptor
2 bInterfaceNumber 1 0x01 Index of this interface
3 bAlternateSetting 1 0x01 Index of this setting
4 bNumEndpoints 1 0x01 Endpoint 1
5 bInterfaceClass 1 0x01 AUDIO
6 bInterfaceSubclass 1 0x02 AUDIO_STREAMING
7 bInterfaceProtocol 1 0x00 Unused
8 iInterface 1 0x00 null string
3.4.3 Class-specific audio streaming interface descriptor
Offset Field Size Value Description
0 bLength 1 0x07 Length of this descriptor
1 bDescriptorType 1 0x24 CS_INTERFACE descriptor
2 bDescriptorSubtype 1 0x01 AS_GENERAL
3 bTerminalLink 1 0x02 Unit ID of terminal(Output Terminal ID)
4 bDelay 1 0x01 Interface delay
5 wFormatTag 2 0x0001 PCM
3.4.4 Type I format type descriptor
Offset Field Size Value Description
0 blength 1 0x17 Size of this descriptor
1 bDescriptorType 1 0x24 CS_INTERFACE
2 bdescriptorSubtype 1 0x02 FORMAT_TYPE
3 bformatType 1 0x01 FORMAT_TYPE_I
4 bNrChannels 1 0x01 One channel
5 bSubFrameSize 1 0x02 Two bytes per slot
6 bBitResolution 1 0x10 16 bits
7 bSamFreqType 1 0x05 Five frequencies
8 tSamFreq[0] 3 0x001F40 8000Hz
11 tSamFreq[1] 3 0x002B11 11025Hz
14 tSamFreq[2] 3 0x005622 22050Hz
17 tSamFreq[3] 3 0x00AC44 44100Hz
20 tSamFreq[4] 3 0x00BB80 48000Hz
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3.5 Endpoint descriptor
3.5.1 Standard Endpoint Descriptor
Offset Field Size Value Description
0 bLength 1 0x09 Length of this descriptor
1 bDescriptorType 1 0x05 ENDPOINT descriptor
2 bendpointAddress 1 0x81 Endpoint 1, IN direction
3 bmAttributes 1 0x05 Isochronous, asynchronous, not shared
4 wMaxPacketSize 2 0x0064 2byte*50sample*1ch=100 byte/frame
6 wInterval 1 0x01 One packet every frame (Must be set to 1)
7 bRefresh 1 0x00
8 bSynchAddress 1 0x00
3.5.2 Class-specific isochronous audio data endpoint descriptor
Offset Field Size Value Description
0 bLength 1 0x07 Size of this descriptor
1 bDescriptorType 1 0x25 CS_ENDPOINT
2 bDescriptorSubtype 1 0x01 GENERAL
3 bmAttributes 1 0x01 Sample rate control
4 bLockDelayUnits 1 0x00 Unused
5 wLockDelay 2 0x0000
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3.5.3 Interface descriptor (Alt = 2, 16bit Stereo)
Offset Field Size Value Description
0 bLength 1 0x09 Length of this descriptor
1 bDescriptorType 1 0x04 INTERFACE descriptor
2 bInterfaceNumber 1 0x01 Index of this interface
3 bAlternateSetting 1 0x02 Index of this setting
4 bNumEndpoints 1 0x01 Endpoint 1
5 bInterfaceClass 1 0x01 AUDIO
6 bInterfaceSubclass 1 0x02 AUDIO_STREAMING
7 bInterfaceProtocol 1 0x00 Unused
8 iInterface 1 0x00 null string
3.5.4 Class-specific audio streaming interface descriptor
Offset Field Size Value Description
0 bLength 1 0x07 Length of this descriptor
1 bDescriptorType 1 0x24 CS_INTERFACE descriptor
2 bDescriptorSubtype 1 0x01 AS_GENERAL
3 bTerminalLink 1 0x02 Unit ID of terminal(Output Terminal ID)
4 bDelay 1 0x01 Interface delay
5 wFormatTag 2 0x0001 PCM
3.5.5 Type I format type descriptor
Offset Field Size Value Description
0 blength 1 0x17 Size of this descriptor
1 bDescriptorType 1 0x24 CS_INTERFACE
2 bdescriptorSubtype 1 0x02 FORMAT_TYPE
3 bformatType 1 0x01 FORMAT_TYPE_I
4 bNrChannels 1 0x02 Two channel
5 bSubFrameSize 1 0x02 Two bytes per slot
6 bBitResolution 1 0x10 16 bits
7 bSamFreqType 1 0x05 Five frequencies
8 tSamFreq[0] 3 0x001F40 8000Hz
11 tSamFreq[1] 3 0x002B11 11025Hz
14 tSamFreq[2] 3 0x005622 22050Hz
17 tSamFreq[3] 3 0x00AC44 44100Hz
20 tSamFreq[4] 3 0x00BB80 48000Hz
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3.6 Endpoint descriptor
3.6.1 Standard Endpoint Descriptor
Offset Field Size Value Description
0 bLength 1 0x09 Length of this descriptor
1 bDescriptorType 1 0x05 ENDPOINT descriptor
2 bendpointAddress 1 0x81 Endpoint 1, IN direction
3 bmAttributes 1 0x05 Isochronous, asynchronous, not shared
4 wMaxPacketSize 2 0x00C8 2byte*50sample*2ch=200 byte/frame
6 wInterval 1 0x01 One packet every frame (Must be set to 1)
7 bRefresh 1 0x00
8 bSynchAddress 1 0x00
3.6.2 Class-specific isochronous audio data endpoint descriptor
Offset Field Size Value Description
0 bLength 1 0x07 Size of this descriptor
1 bDescriptorType 1 0x25 CS_ENDPOINT
2 bDescriptorSubtype 1 0x01 GENERAL
3 bmAttributes 1 0x01 Sample rate control
4 bLockDelayUnits 1 0x00 Unused
5 wLockDelay 2 0x0000
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3.7 String descriptor 1
String descriptors use UNICODE. except for LANGID.
3.7.1 LANGID (0x00) Field
Offset Field Size Value Description
0 bLength 1 0x04 Length of this descriptor
1 bDescriptorType 1 0x03 STRING descriptor
2 bString 2 0x0409 “English(US)”
3.7.2 iManufacterer (0x01) Field in Device Descriptor
Offset Field Size Value Description
0 bLength 1 0x34 Length of this descriptor
1 bdescriptorType 1 0x03 STRING descriptor
2 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
“AKM ”
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3.7.3 iProduct (0x02) Field in Device Descriptor
Offset Field Size Value Description
0 bLength 1 0x34 Length of this descriptor
1 bDescriptorType 1 0x03 STRING descriptor
2 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
“AK5371 ”
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4 Standard requests
4.1 Clear Feature
The AK5371A accepts “Clear Feature” request without stall. Though this request does not influence to the
operation of the device, the AK5371A does not support this request.
4.2 Get Configuration
The AK5371A returns Configuration value.
Offset
Field Size Value Description
0 bmRequestType 1 0x80
1 bRequest 1 0x08 GET_CONFIGURATION
2 wValue 2 0x0000
4 wIndex 2 0x0000
6 wLength 2 0x0001 AKM USB Mic. has one configuration.
4.3 Get Descriptor
Offset Field Size Value Description
0 bmRequestType 1 0x80
1 bRequest 1 0x06 GET_DESCRIPTOR
2 wValue 2 0xZZZZ 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)
4 wIndex 2 0x0000 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)”.
6 wLength 2 0xZZZZ Descriptor Length (ZZZZ is assigned by host)
4.4 Get Interface
The AK5371A 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
0x0001
Audio Control Interface
Audio Streaming Interface
6 wLength 2 0x0001 AKM USB Mic. Has zero bandwidth Audio
Streaming Interface and normal Audio Streaming
Interface.
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4.5 Get Status
Offset Field Size Value Description
0 bmRequestType 1 0x80
0x81
0x82
DEVICE
INTERFACE
ENDPOINT
1 bRequest 1 0x00 GET_STATUS
2 wValue 2 0x0000 ZERO
4 wIndex 2 0x0000
0x0000
0x0001
0x0000
0x0081
bmRequestType is DEVICE
bmRequestType is Audio Control Interface
bmRequestType is Audio Streaming Interface
bmRequestType is Audio Control Endpoint
bmRequestType is Audio Streaming Endpoint
6 wLength 2 0x0002
The AKM USB MIC returns the following status.
a)Device : 0x0000( AKM USB MIC is bus-powered device)
b)Interface: 0x0000 (All Zero)
c)Endpoint : 0x0000
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
0x0001
others
Unconfigured State
AKM USB MIC is set to configured state
Invalid
4 wIndex 2 0x0000 Zero
6 wLength 2 0x0000 Zero
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4.8 Set Feature
The AK5371A accepts “Set Feature” request without stall. However note that the AK5371A 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
0x0000
0x0001
0x0002
Alternate Setting
Control Interface or Zero Bandwidth
16bit Mono
16bit Stereo
4 wIndex 2 0x0000
0x0001
Audio Control Interface
Audio Streaming Interface
6 wLength 2 0x0000 Zero
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5 Device specific Requests
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
0x00
TRUE
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
0x0202
VOLUME_CONTROL | CHANNEL_1
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 AK5371A forces the value into the range. Please see the conversion table in
the Get Feature Unit Control Request.
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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
0x00
TRUE
FALSE
b) Volume Control
Offset Field Size Value Description
0 bmRequestType 1 0xA1
1 bRequest 1 0x81
0x82
0x83
0x84
GET_CUR
GET_MIN
GET_MAX
GET_RES
2 wValue 2 0x0201
0x0202
VOLUME_CONTROL | CHANNEL_1
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 Volume Control is the following.
Offset Field Size Value Description
0 wVolume 2 0xZZYY
0xE100
0x1800
0x0100
bRequest = GET_CUR : returns current volume.
YY must be 00h
bRequest = GET_MIN : -31dB
bRequest = GET_MAX : +24dB
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.
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Field
wVolume
Internal
Value
value Step
0x7FFF 0x1800 24.0000
-------- ------ ---------
0x1800 0x1800 24.0000
0x17FF 0x1700 23.0000
--------- ------ --------
0x1701 0x1700 23.0000
0x1700 0x1700 23.0000
0x16FF 0x1600 22.0000
--------- ------ --------
0x1201 0x1200 18.0000
0x1200 0x1200 18.0000
--------- --------- --------
--------- --------- --------
0x02FF 0x0200 2.0000
--------- --------- --------
0x0201 0x0200 2.0000
0x0200 0x0200 2.0000
0x01FF 0x0100 1.0000
--------- --------- ---------
0x0101 0x0100 1.0000
0x0100 0x0100 1.0000
0x00FF 0x0000 0.0000
--------- --------- ---------
0x0001 0x0000 0.0000
0x0000 0x0000 0.0000 1.0dB
0xFFFF 0xFF00 -1.0000
-------- -------- --------
0xFF01 0xFF00 -1.0000
0xFF00 0xFF00 -1.0000
0xFEFF 0xFE00 -2.0000
-------- -------- --------
0xFE01 0xFE00 -2.0000
0xFE00 0xFE00 -2.0000
--------- --------- ---------
--------- --------- ---------
0xE200 0xE200 -30.0000
0xE1FF 0xE100 -31.0000
--------- --------- ---------
0xE101 0xE100 -31.0000
0xE100 0xE100 -31.0000
0xE1FF 0xE100 -31.0000
--------- ---------
0x8000 0xE100 -31.0000
Table 1 Conversion Table of Volume Control
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5.2 Endpoint Control Request
The AK5371A 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 Field Size Value Description
0 bmRequestType 1 0x22
1 bRequest 1 0x01 SET_CUR
2 wValue 2 0x0100 Upper byte: SAMPLING_FREQ_CONTROL (0x01)
Lower byte : zero
4 wIndex 2 0x0081 Upper Byte : zero
Lower Byte : Endpoint Address (0x81)
6 wLength 2 0x0003 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 AK5371A forces sampling frequency to the
appropriate value.
5.2.2 Get Endpoint Control Request
Offset Field Size Value Description
0 bmRequestType 1 0xA2
1 bRequest 1 0x81 GET_CUR
2 wValue 2 0x0100 Upper byte: SAMPLING_FREQ_CONTROL (0x01)
Lower byte : zero
4 wIndex 2 0x0081 Upper Byte : zero
Lower Byte : Endpoint Address (0x81)
6 wLength 2 0x0003 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
0x00BB80 : 48kHz
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Package (AK5371AVQ)
1
12
48 13
7.0
9.0 ± 0.2
7.0
9.0 ± 0.2
0.19 ± 0.05
48
p
in LQFP
(
Unit:mm
)
0.10
37
12 24
2536
0.17 ± 0.05
1.4TYP
0.10 ± 0.07
1.70Ma
x
0° ∼ 10°
0.10 M
0.5
±
0.2
0.5
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Marking (AK5371AVQ)
A
K5371AVQ
XXXXXXX
1
1) Pin #1 indication
2) Date Code: XXXXXXX (7 digits)
3) Marking Code: AK5371AVQ
4) Asahi Kasei Logo
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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., L td. (AKM) sales
office or authorized distributor concerning their current status.
• AKM assumes no liab ility for infringement o f any patent, intelle ctual property, or other righ t 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 of ficial approval under the law and regula tions of the co untry of export pert aining
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, e xcept with the expres s 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 re spon sibility 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.
