AD9742AR

Digital To Analog Converters Overview

The AD9742AR is a 12-bit, wideband digital-to-analog converter (DAC) from the TxDAC family. It supports update rates up to 210 MSPS with a typical output settling time of 11 ns. The device operates on single supplies ranging from 2.7 V to 3.6 V for analog (AVDD), digital (DVDD), and clock (CLKVDD) domains. Key electrical specifications include an Integral Nonlinearity (INL) of ±0.5 LSB and Differential Nonlinearity (DNL) of ±0.4 LSB at full-scale current. It features differential current outputs adjustable between 2 mA and 20 mA, an integrated 1.2 V temperature-compensated bandgap reference, and CMOS-compatible parallel digital inputs.

Digital To Analog Converters Feature Summary

• High-speed performance: Supports conversion rates up to 210 MSPS with 11 ns settling time.
• Integrated reference: Includes a 1.2 V bandgap voltage reference; external override capability available.
• Low power consumption: Dissipates 135 mW at 3.3 V; reduces to 15 mW in power-down mode.
• Flexible architecture: Offers segmented current source design for enhanced dynamic performance and spurious-free dynamic range.

Digital To Analog Converters Applications

• Wideband communication transmit channels
• Direct IF base stations
• Wireless local loops
• Digital radio links
• Direct digital synthesis (DDS)

Digital To Analog Converters Procurement Notes

Verify the package type matches the required footprint, as the AD9742 series is available in 28-lead SOIC, 28-lead TSSOP, and 32-lead LFCSP configurations. Confirm that the specific suffix corresponds to the desired packaging format before procurement. Ensure supply voltages align with the 2.7 V to 3.6 V operational range specified in the datasheet.

Digital To Analog Converters Selection Notes

Select the AD9742AR when a 12-bit resolution is sufficient for the application, distinguishing it from the pin-compatible 8-bit (AD9748), 10-bit (AD9740), and 14-bit (AD9744) variants. Consider the 210 MSPS maximum update rate and the need for differential current outputs. Evaluate power requirements against the 135 mW typical dissipation or the reduced power options via full-scale current adjustment.

Digital To Analog Converters Part Context

The AD9742 is part of the third-generation TxDAC product family, designed specifically for transmit signal paths in communication systems. It shares pinouts and interface options with other members of the family, allowing for scalable component selection based on resolution and cost. The device utilizes a proprietary switching technique combined with a segmented current source architecture to minimize spurious components.

Digital To Analog Converters Replacement Considerations

Pin-compatible alternatives within the same family include the AD9740 (10-bit), AD9744 (14-bit), and AD9748 (8-bit). These devices share identical package footprints and interface logic, facilitating direct substitution if resolution adjustments are acceptable. Verify that the alternative device's speed and linearity specifications meet the system requirements.