AD9709 8-Bit, 125 MSPS Dual TxDAC+ Digital-to-Analog Converter

The AD9709 has been optimized for processing I and Q data in communications applications. The digital interface consists of two double-buffered latches as well as control logic. Separate write inputs allow data to be written to the two DAC ports independent of one another. Separate clocks control the update rate of the DACs A mode control pin allows the AD9709 to interface to two separate data ports, or to a single interleaved high speed data port. In interleaving mode, the input data stream is demuxed into its original I and Q data and then latched. The I and Q data is then converted by the two DACs and updated at half the input data rate. The GAINCTRL pin allows two modes for setting the full-scale current (IOUTFS) of the two DACs. IOUTFS for each DAC can be set independently using two external resistors, or IOUTFS for both DACs can be set by using a single external resistor. See the Gain Control Mode section for important date code information on this feature. The DACs utilize a segmented current source architecture combined with a proprietary switching technique to reduce glitch energy and to maximize dynamic accuracy. Each DAC provides differential current output, thus supporting single-ended or differential applications. Both DACs can be simultaneously updated and provide a nominal full-scale current of 20 mA. The full-scale currents between each DAC are matched to within 0.1%. The AD9709 is manufactured on an advanced low-cost CMOS process. It operates from a single supply of 3.3 V or 5 V and consumes 380 mW of power. Product Highlights The AD9709 is a member of a pin-compatible family of dual TxDACs providing 8-, 10-, 12-, and 14-bit resolution. Dual 8-Bit, 125 MSPS DACs. A pair of high performance DACs optimized for low distortion performance provide for flexible transmission of I and Q information. Matching. Gain matching is typically 0.1% of full scale, and offset error is better than 0.02%. Low Power. Complete CMOS dual DAC function operates at 380 mW from a 3.3 V or 5 V single supply. The DAC full-scale current can be reduced for lower power operation, and a sleep mode is provided for low power idle periods. On-Chip Voltage Reference. The AD9709 includes a 1.20 V temperature-compensated band gap voltage reference. Dual 8-Bit Inputs. The AD9709 features a flexible dual-port interface, allowing dual or interleaved input data. Applications Communications Base stations Digital synthesis Quadrature modulation 3D ultrasound

The AD9709 is a dual-port, high speed, 2-channel, 8-bit CMOS DAC. It integrates two high quality 8-bit TxDAC+® cores, a voltage reference, and digital interface circuitry into a small 48-lead LQFP package. The AD9709 offers exceptional ac and dc performance while supporting update rates of up to 125 MSPS.

The AD9709 has been optimized for processing I and Q data in communications applications. The digital interface consists of two double-buffered latches as well as control logic. Separate write inputs allow data to be written to the two DAC ports independent of one another. Separate clocks control the update rate of the DACs

A mode control pin allows the AD9709 to interface to two separate data ports, or to a single interleaved high speed data port. In interleaving mode, the input data stream is demuxed into its original I and Q data and then latched. The I and Q data is then converted by the two DACs and updated at half the input data rate.

The GAINCTRL pin allows two modes for setting the full-scale current (IOUTFS) of the two DACs. IOUTFS for each DAC can be set independently using two external resistors, or IOUTFS for both DACs can be set by using a single external resistor. See the Gain Control Mode section for important date code information on this feature.

The DACs utilize a segmented current source architecture combined with a proprietary switching technique to reduce glitch energy and to maximize dynamic accuracy. Each DAC provides differential current output, thus supporting single-ended or differential applications. Both DACs can be simultaneously updated and provide a nominal full-scale current of 20 mA. The full-scale currents between each DAC are matched to within 0.1%.

The AD9709 is manufactured on an advanced low-cost CMOS process. It operates from a single supply of 3.3 V or 5 V and consumes 380 mW of power.

Product Highlights
  • The AD9709 is a member of a pin-compatible family of dual TxDACs providing 8-, 10-, 12-, and 14-bit resolution.
  • Dual 8-Bit, 125 MSPS DACs. A pair of high performance DACs optimized for low distortion performance provide for flexible transmission of I and Q information.
  • Matching. Gain matching is typically 0.1% of full scale, and offset error is better than 0.02%.
  • Low Power. Complete CMOS dual DAC function operates at 380 mW from a 3.3 V or 5 V single supply. The DAC full-scale current can be reduced for lower power operation, and a sleep mode is provided for low power idle periods.
  • On-Chip Voltage Reference. The AD9709 includes a 1.20 V temperature-compensated band gap voltage reference.
  • Dual 8-Bit Inputs. The AD9709 features a flexible dual-port interface, allowing dual or interleaved input data.

Applications

Features and Benefits
  • 8-bit dual transmit digital-to-analog converter (DAC)
  • 125 MSPS update rate
  • Excellent SFDR to Nyquist @ 5 MHz output: 66 dBc
  • Excellent gain and offset matching: 0.1%
  • Fully independent or single-resistor gain control
  • Dual port or interleaved data
  • On-chip 1.2 V reference
  • See Data Sheet for Additional Information
Digital to Analog Converters
AD9709 IBIS Models
Data Sheets
Documentnote
AD9709: 8-Bit, 125 MSPS Dual TxDAC+® D/A Converter Data Sheet (Rev. B)PDF 2523 kB
Application Notes
Documentnote
AN-237: Choosing DACs for Direct Digital SynthesisPDF 1156 kB
AN-595: Understanding Pin Compatibility in the TxDAC® Line of High Speed D/A Converters (Rev. 0)PDF 36 kB
AN-912: Driving a Center-Tapped Transformer with a Balanced Current-Output DAC (Rev. 0)PDF 246 kB
AN-320A: CMOS Multiplying DACs and Op Amps Combine to Build Programmable Gain Amplifier, Part 1PDF 1295 kB
AN-555: Using the AD9709, AD9763, AD9765, AD9767 Dual DAC Evaluation Board (Rev. 0)PDF 206 kB
Order Information
Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
AD9709ASTZ Production48 ld LQFPOTH 250-40 to 85C6.155.23Y
AD9709ASTZRL Production48 ld LQFPREEL 2000-40 to 85C05.23Y
Evaluation Boards
Part NumberDescriptionPriceRoHS
AD9709-EBZEvaluation Board303.6Y
Reference Materials
AD9709: 8-Bit, 125 MSPS Dual TxDAC+® D/A Converter Data Sheet (Rev. B) ad9709
AD9709AST 3V ad9709
AD9709AST 5V ad9709
AN-237: Choosing DACs for Direct Digital Synthesis ad9856
AN-595: Understanding Pin Compatibility in the TxDAC® Line of High Speed D/A Converters (Rev. 0) ad9760
AN-237: 放大器直接数字频率合成的DAC选型器应用漫谈 (Rev. 0) ad9540
AN-912: 用平衡电流输出DAC驱动中心抽头变压器[中文版] (Rev. 0) ad7524
AN-912: Driving a Center-Tapped Transformer with a Balanced Current-Output DAC (Rev. 0) ad7524
AN-320A: CMOS Multiplying DACs and Op Amps Combine to Build Programmable Gain Amplifier, Part 1 ad7524
AN-595: 了解TxDAC®系列高速DAC的引脚兼容性[中文版] (Rev. 0) ad9760
AN-555: Using the AD9709, AD9763, AD9765, AD9767 Dual DAC Evaluation Board (Rev. 0) ad9763
Digital to Analog Converters ICs Solutions Bulletin ad5590