Analog Devices Inc. AD1974 24 位模数转换器
Analog Devices AD1974 24 位模数转换器 (ADC) 是一款高性能的单芯片模数转换器，采用获得专利的多比特 Σ-Δ 架构，可提供 4 个带差分输入的模数转换器。 AD1974 在系统和电路设计架构上都针对低电磁干扰 (EMI) 而设计。 这些 ADC 设计为采用 Analog Devices 公司最新的连续时间架构，可使电磁干扰进一步降低。 设计人员可利用板载锁相环驱动 LR 时钟或外部晶振的主时钟。 这种设计不需要单独的高频主时钟，而且可与抑制位时钟配合使用。 AD1974 ADC 采用 3.3V 数字和模拟电源供电，实现了最低功耗，进一步降低了电磁辐射。 AD1974 的 SPI 端口允许微控制器启用静音以及调整众多其他参数。 AD1974 ADC 非常适合用于汽车音频系统、家庭影院系统、机顶盒处理器和数字音频效果处理器。
Designers can use the onboard phase-locked loop (PLL) to derive the master clock from the LR clock or from an external crystal. This design eliminates the need for a separate high-frequency master clock and allows the device to be used with a suppressed bit clock.
TheAD1974 ADCs operate from 3.3V digital and analog supplies to minimize power consumption and reduce emissions. AD1974's SPI port allows a microcontroller to enable mutes as well as adjust many other parameters. The AD1974 ADCs are ideal for automotive audio systems, home theater systems, set-top processors, and digital audio effects processors.
特性
- Phase-locked loop generated or direct master clock
- Low EMI design
- 107dB dynamic range and SNR
- −94dB THD + N
- Single 3.3V supply
- Tolerance for 5V logic inputs
- Supports 24 bits and 8kHz to 192kHz sample rates
- Differential ADC input
- SPI®-controllable for flexibility
- Software-controllable clickless mute
- Software power-down
- Right justified, left-justified, I²S, and TDM modes
- Master and slave modes up to 16-channel input/output
- Available in a 48-lead LQFP
- Qualified for automotive applications
应用
- Automotive audio systems
- Home theater systems
- Set-top boxes
- Digital audio effects processors
Functional Block Diagram
Evaluation Tools
EVAL-AD1974AZ Evaluation board for the Analog Devices AD1974 24-Bit ADCs.
EVAL-ADUSB2EBZ USBi “USB Interface” board. Interfaces between the PC's USB port and SigmaDSP hardware's data input pins. The EVAL-ADUSB2EBZ board is capable of both SPI and I²C communication (which is user selectable). The board can also supply IOVDD of either 3.3V or 1.8V. The USBi interface is powered from the computer's USB port.