AK5373带USB 2.0接口立体声模数转换技术

AKM 公司的AK5373是带USB 2.0接口的立体声模数转换器（ADC），包括有USB串行接口引擎，USB收发器，音频处理区块，端点以及24位立体声音频ADC。集成的PLL可使用多种取样频率，并集成了麦克风放大器和可编程增益放大器。工作电压3.0V-3.6V。本文介绍了AK5373主要特性，方框图，内部ADC流模式，外部音频处理模式以及系统连接框图，AKD5373-A评估板方框图和电路图与元件布局图。

AK5373主要特性：

USB 2.0 compliant (full speed audio class)

USB audio controller

USB serial interface engine

Audio class encoder/decoder

USB synchronization

Synchronous type (synchronize with 1ms SOF)

24-bit stereo A/D converter with mute control

S/(N+D) = 85dB, S/N = 91dB (AVDD=3.3V, MIC-Amp = 0dB)

S/(N+D) = 70dB, S/N = 78dB (AVDD=3.3V, MIC-Amp = +30dB)

Microphone amplifier gain:

0dB, +6dB, +12dB, +18dB, +24dB, +30dB, +36dB

Digital programmable gain: +24dB ~ -31dB, 1dB Step

Integrated PLL supports standard sampling frequencies

8kHz, 11.025kHz, 16kHz, 22.05kHz, 32kHz 44.1kHz, 48kHz

EEP-ROM interface for descriptors

External Digital Audio Interface

Power Management

Low power consumption

30mA in active mode

Less than 100μA in suspend mode

Power Supply:

Analog Power Supply (AVDD): 3.0 ~ 3.6V

Digital Power Supply (DVDD): 3.0 ~ 3.6V

Ta = -10 ~ +70℃

Package:

48pin LQFP (7 x 7 mm, 0.5mm pitch)

图1。AK5373方框图

图2。内部ADC流模式

图3。外部音频处理模式

图4。AK5373系统连接框图

AKD5373-A评估板

AKD5373-A is an evaluation board for AK5373, which is a stereo A/D Converter with a USB 2.0 interface. The AK5373 can be tested easily on the AKD5373-A, as the operation of the device is compatible with USB standard audio class. The AKD5373-A has not only an external audio interface, but also an external EEP-ROM that all descriptor contents are stored and customizable.

图5。AKD5373-A评估板方框图


图6。AKD5373-A评估板电路图（1）

图7。AKD5373-A评估板电路图（2）

图8。AKD5373-A评估板顶视图