AKM 公司的AK5373是帶USB 2.0接口的立體聲模數(shù)轉(zhuǎn)換器（ADC），包括有USB串行接口引擎，USB收發(fā)器，音頻處理區(qū)塊，端點以及24位立體聲音頻ADC。集成的PLL可使用多種取樣頻率，并集成了麥克風放大器和可編程增益放大器。工作電壓3.0V-3.6V。本文介紹了AK5373主要特性，方框圖，內(nèi)部ADC流模式，外部音頻處理模式以及系統(tǒng)連接框圖，AKD5373-A評估板方框圖和電路圖與元件布局圖。
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)
圖1。AK5373方框圖
圖2。內(nèi)部ADC流模式
圖3。外部音頻處理模式
圖4。AK5373系統(tǒng)連接框圖
AKD5373-A評估板
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.
圖5。AKD5373-A評估板方框圖
圖6。AKD5373-A評估板電路圖（1）
圖7。AKD5373-A評估板電路圖（2）
圖8。AKD5373-A評估板頂視圖