AD1940YST

Overview

The AD1940YST is a 28-bit multichannel audio SigmaDSP processor in a 48-lead LQFP package. It features a hardware-accelerated DSP core with a 28-bit × 28-bit multiplier and full 56-bit accumulator, supporting sample rates up to 192 kHz. The device includes 21 kB of data memory for audio delay and fully programmable RAM for custom algorithms. It offers 16-channel digital audio processing via flexible serial ports (I2S, TDM) and an SPI control interface. Operating from a 2.5 V supply with an on-chip regulator for 3.3 V/5 V compatibility, it functions within a –40°C to +105°C ambient temperature range.

Feature Summary

• 16-channel digital audio processor with 28-bit × 28-bit multiplier and 56-bit double-precision accumulation
• 21 kB data memory providing up to 128 ms of audio delay at 48 kHz sampling rate
• Flexible serial I/O supporting I2S, left/right-justified, and 8/16-channel TDM modes
• SPI control port with safeload feature for transparent parameter updates

Applications

• Automotive sound systems
• Home theater systems (Dolby Digital/DTS postprocessor)
• Digital speaker crossovers
• Multichannel audio systems

Procurement Notes

Verify the specific suffix 'YST' against the manufacturer's official ordering guide to confirm pinout, temperature grade, or packaging variations. Confirm availability status as distribution channels may vary. Ensure ESD precautions are observed during handling due to the sensitivity of the CMOS process.

Selection Notes

Select the AD1940 variant if SPI control is required; the AD1941 uses I2C. Ensure the system master clock aligns with the PLL input requirements (64x, 256x, 384x, or 512x fs). Verify that the external voltage supply matches the VSUPPLY pin requirements for the internal regulator operation.

Part Context

The AD1940 is part of Analog Devices' SigmaDSP family, designed for high-performance audio signal processing. It integrates a programmable DSP core with dedicated memory structures for coefficients and parameters, enabling complex audio algorithms such as equalization, dynamic range compression, and crossover filtering without external microcontrollers.

Replacement Considerations

The AD1941 is functionally identical but utilizes an I2C control interface instead of SPI. Other SigmaDSP devices may offer different channel counts or precision levels but require software reconfiguration.