AD9851BRS

Overview

The AD9851BRS is a CMOS Direct Digital Synthesis (DDS) frequency synthesizer and clock generator manufactured by Analog Devices Inc. It integrates a high-speed 10-bit digital-to-analog converter (DAC) and a comparator with hysteresis to generate stable, phase-programmable sine waves or square waves. The device supports an 180 MHz system clock rate, featuring a selectable 6x reference clock multiplier that allows operation with lower external reference frequencies. It accepts a 32-bit frequency tuning word for precise frequency control and offers simplified parallel or serial asynchronous loading interfaces. Operating on a single supply voltage ranging from 2.7 V to 5.25 V, the component provides low power consumption and includes a power-down function. It is housed in a 28-lead Shrink Small Outline Package (SSOP).

Feature Summary

• Integrates a high-performance 10-bit DAC and a high-speed comparator with hysteresis for direct analog and digital output generation.
• Features a 32-bit frequency tuning word enabling high-resolution frequency synthesis and phase modulation capabilities.
• Includes a selectable 6x reference clock multiplier to facilitate system clock generation from lower frequency inputs.
• Supports simplified control via parallel or serial asynchronous loading formats for flexible interface integration.

Applications

• Frequency/phase-agile sine wave synthesis for signal generation.
• Clock recovery and locking circuitry for digital communications systems.
• Digitally controlled ADC encode generators.
• Agile local oscillator applications in communication transceivers.
• CW, AM, FM, FSK, and MSK mode transmitter implementations.

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current documentation to confirm package type and temperature range. Ensure compatibility with required supply voltages and clock input levels before integration. Confirm RoHS compliance status through official datasheets. Validate pinout configurations for SSOP-28 mounting requirements during PCB design.

Selection Notes

Select this component when high-frequency resolution and fast frequency agility are required within a compact footprint. Consider the internal 6x multiplier if only lower frequency reference clocks are available. Evaluate power dissipation limits at maximum clock rates and verify thermal management for the SSOP package. Ensure the control interface matches the host processor's capabilities for parallel or serial data loading.

Part Context

The AD9851 belongs to Analog Devices' family of Direct Digital Synthesis devices, designed for precise frequency and phase control. It utilizes advanced DDS technology combined with high-speed conversion components to replace traditional analog synthesizers in many applications. The BRS variant specifically denotes the industrial temperature range and SSOP packaging option within the product line.

Replacement Considerations

AD9851BRSRL