AK5371AVQ AKM [Asahi Kasei Microsystems], AK5371AVQ Datasheet - Page 10

• Manufacturer Part Number: AK5371AVQ
• Description: 2ch A/D Converter with USB I/F
• Manufacturer: AKM [Asahi Kasei Microsystems]

MS0546-E-00
The AK5371A is the advanced stereo A/D converter, which converts analog 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, memory, 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:
frequencies, the AK5371A incorporates PLL, which generates system clock and master clock for fs=8kHz, and 48kHz
master clock stop the function to observe USB specification, 500μA , until receiving the resume signal. The AK5371A notifies the
current state (normal state or suspend state) by SUS_N pin.
their own ID, and string.
The AK5371A supports 5 sampling frequencies (8kHz, 11.025kHz, 22.05kHz, 44.1kHz, 48kHz). In order to support these
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
As the AK5371A has Microwire™ EEPROM I/F, the vendors can customize iManifacterer, iProduct, and the related strings to
Overview of AK5371A
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ASAHI KASEI
MS0103-E-00
2 channel 16bit A/D converter
Programmable Gain Amplifier (IPGA)
Fixed Gain Preamplifier
FIFO
Synchronization between A/D converter and USB bus
PLL
Audio Format
USB Serial Interface Engine
Control block of Audio Device Class
USB transceiver
EEPROM I/F
USB Suspend/Resume Support
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Microwire™ (4-wire) type EEPROM can be used to customize Device/String Descriptor.
20dB
Memory Size 400 bytes (16bit wide x 100 depth x 2 channel)
Gain Range: from +24dB to -31dB,
Gain Step: 1dB/step
84dBA@fs=44.1kHz
11.2896MHz crystal
Two PLLs
supports 5 frequencies : 8kHz, 11.025kHz, 22.05kHz, 44.1kHz, 48kHz
2 audio formats
Process USB Standard Requests
Translate internal A/D format to USB audio class format
Process USB Audio Class Request
- A/D_PLL: generate clock for fs=8kHz, 48kHz
- System_PLL : generate USB system clock
- Mute
- Gain/Attenuation
- Sampling Frequency Control
- 1K bit (AK93C45A)
- 2K bit (AK93C55A)
- 4Kbit (AK93C65A)
- mono 16bit LSB first
- stereo 16bit LSB first
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[AK5371A]
2007/02