Analog Devices Inc. AD1974 24-Bit ADCs
Analog Devices AD1974 24-Bit analog-to-digital converters (ADCs) are single-chip, high-performance ADCs offering four ADCs with differential inputs developed using patented multi-bit sigma-delta (Σ-Δ) architecture. AD1974's system and circuit design architectures were developed with EMI in mind. The ADCs are designed using the latest continuous-time architectures from Analog Devices to minimize EMI.
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.
Features
- 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
Applications
- 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.