AD9831AST

Overview

The AD9831AST is a Direct Digital Synthesizer (DDS) numerically controlled oscillator. It integrates a phase accumulator, sine look-up table, and 10-bit D/A converter. The device supports clock frequencies up to 25 MHz and enables both phase modulation and frequency modulation via a parallel microprocessor interface. Operating voltage ranges from 2.97 V to 5.5 V. Power consumption is specified at 40 mW for 3 V operation and 125 mW for 5 V operation. The component is housed in a 48-pin LQFP package.

Feature Summary

• Integrates a phase accumulator, sine look-up table, and 10-bit D/A converter within a single CMOS chip.
• Supports frequency modulation and phase modulation through a parallel microprocessor interface.
• Includes external control options for shutdown mode and internal reference selection.

Applications

• Direct digital synthesis of waveforms
• Frequency modulation signal generation
• Phase modulation applications

Procurement Notes

Verify the specific ordering suffix against official Analog Devices documentation to confirm package type and temperature range. Confirm current production status as availability may vary by region or revision. Ensure compatibility with required supply voltages and interface logic levels before procurement.

Selection Notes

Select this component when a parallel interface is preferred over serial alternatives like the AD9832. Verify that the 25 MHz maximum clock rate meets system timing requirements. Consider power consumption differences between 3 V and 5 V operating modes during design.

Part Context

The AD9831 is part of the Analog Devices DDS family, which includes variants such as the AD9830, AD9832, and AD9833. These devices share core DDS architecture but differ in interface types (parallel vs. serial) and maximum clock speeds. The AD9831 specifically utilizes a parallel data bus for register loading.

Replacement Considerations

Public confirmed substitutes include AD9831ASTZ and AD9831ASTZ-REEL. Verify pinout and electrical specifications match the original design requirements before substitution.