Overview
The AD9831AST from Analog Devices Inc. is a Direct Digital Synthesizer (DDS) device that integrates a numerically controlled oscillator, a sine look-up table, and a 10-bit Digital-to-Analog Converter (DAC) on a single CMOS chip. This device is designed to generate high-quality sine waves and is capable of frequency and phase modulation. It operates with a 3 V or 5 V power supply and supports a clock speed of up to 25 MHz. The AD9831AST is particularly useful in applications requiring precise frequency synthesis and modulation capabilities.
Key Specifications
| Parameter | Value | Units | Test Conditions/Comments |
|---|---|---|---|
| Resolution | 10 Bits | ||
| Update Rate (fMAX) | 25 MSPS | nominal | |
| IOUT Full Scale | 4 mA (nom), 5 mA (max) | ||
| Output Compliance | 1.5 V (max) | ||
| DC Accuracy - Integral Nonlinearity | ±1 LSB (typ) | ||
| DC Accuracy - Differential Nonlinearity | ±0.5 LSB (typ) | ||
| Signal to Noise Ratio | 50 dB (min) | fMCLK = 25 MHz, fOUT = 1 MHz | |
| Total Harmonic Distortion | -53 dBc (max) | fMCLK = 25 MHz, fOUT = 1 MHz | |
| Spurious Free Dynamic Range (SFDR) | -72 dBc (min) at 5 V, -70 dBc (min) at 3 V | fMCLK = 6.25 MHz, fOUT = 2.11 MHz, Narrow Band (±50 kHz) | |
| Clock Feedthrough | -60 dBc (typ) | ||
| Wake-Up Time | 1 ms (typ) | ||
| Powerdown Option | Yes | ||
| Power Consumption | 125 mW (5 V), 40 mW (3 V) |
Key Features
- 3 V or 5 V power supply
- Up to 25 MHz clock speed
- On-chip sine look-up table and 10-bit DAC
- Parallel loading and powerdown option
- High SFDR of up to 72 dBc
- Frequency and phase modulation capabilities
- Low power consumption: 125 mW at 5 V, 40 mW at 3 V
- Wake-up time of 1 ms
- Internal high impedance current source DAC
Applications
- DDS tuning
- Digital demodulation
- Digital radio systems
- Software-defined radios
- RF/Communications systems
Q & A
- What is the AD9831AST used for?
The AD9831AST is used for generating high-quality sine waves and is particularly useful in applications requiring precise frequency synthesis and modulation capabilities.
- What are the power supply options for the AD9831AST?
The AD9831AST can operate with either a 3 V or 5 V power supply.
- What is the maximum clock speed of the AD9831AST?
The maximum clock speed of the AD9831AST is 25 MHz.
- Does the AD9831AST support frequency and phase modulation?
Yes, the AD9831AST supports both frequency and phase modulation.
- What is the resolution of the DAC in the AD9831AST?
The DAC in the AD9831AST has a resolution of 10 bits.
- What is the typical wake-up time of the AD9831AST from powerdown mode?
The typical wake-up time is 1 ms.
- What are some common applications of the AD9831AST?
Common applications include DDS tuning, digital demodulation, digital radio systems, software-defined radios, and RF/Communications systems.
- How does the AD9831AST manage power consumption?
The AD9831AST has a powerdown option and consumes 125 mW at 5 V and 40 mW at 3 V.
- What is the SFDR of the AD9831AST?
The SFDR of the AD9831AST is up to 72 dBc.
- How is the output current of the DAC controlled in the AD9831AST?
The output current of the DAC can be adjusted using a single external resistor (RSET).
