Features and Benefits
- 180 MHz Clock Rate with Selectable 6x Reference Clock Multiplier
- On-Chip High Performance 10-Bit DAC and High Speed Comparator with Hysteresis
- SFDR >43 dB @ 70 MHz AOUT
- 32-Bit Frequency Tuning Word
- Simplified Control Interface: Parallel or Serial Asynchronous Loading Format
- 5-Bit Phase Modulation and Offset Capability
- Comparator Jitter <80 ps p-p @
- 2.7 V to 5.25 V Single-Supply Operation
- Low Power: 555 mW @ 180 MHz
- Power-Down Function, 4 mW @ 2.7V
- Ultrasmall 28-Lead SSOP Packaging
The AD9851 is a highly integrated device that uses advanced DDS technology, coupled with an internal high-speed, high performance D/A converter, and comparator, to form a digitally-programmable frequency synthesizer and clock generator function. When referenced to an accurate clock source, the AD9851 generates a stable frequency and phase-programmable digitized analog output sinewave. This sinewave can be used directly as a frequency source, or internally converted to a square wave for agile-clock generator applications.
The AD9851's innovative high-speed DDS core provides a 32-bit frequency tuning word, which results in an output tuning resolution of 40 milli-Hertz, for a 180 MHz reference clock. The AD9851 contains a unique X6 reference clock multiplier circuit that obviates the need for a high-speed reference oscillator. The 6X PLL multiplier has minimal impact on SFDR and phase noise characteristics. The device provides 5-bits of digitally-controlled phase modulation which enables phase shifting of its output in increments of 180°, 90°, 45°, 22.5°, 11.25°, and any combination thereof.
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Application Notes (23)
Tools & Simulations
ADIsimDDS uses mathematical equations to model and illustrate the overall performance of the selected device. ADIsimDDS calculates the required FTW, given the reference clock frequency and desired output frequency. This tool also models an estimate of the overall spectral performance, and allows the user to explore the effects of external reconstruction filters.
Technical Articles (21)
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.