AD9778 Dual 14-Bit, 1 GSPS, Digital-to-Analog Converter _ BDTIC a Leading Distributor in China

AD9778 Dual 14-Bit, 1 GSPS, Digital-to-Analog Converter

Ultralow noise and intermodulation distortion (IMD) enable high quality synthesis of wideband signals from baseband to high intermediate frequencies. A proprietary DAC output switching technique enhances dynamic performance. The current outputs are easily configured for various single-ended or differential circuit topologies. CMOS data input interface with adjustable set up and hold. Novel 2×, 4×, and 8× interpolator/coarse complex modulator allows carrier placement anywhere in DAC bandwidth. Applications Wireless infrastructure WCDMA, CDMA2000, TD-SCDMA, WiMax, GSM Digital high or low IF synthesis Internal digital upconversion capability Transmit diversity Wideband communications: LMDS/MMDS, point-to-point Data Sheet, Rev. A, 3/07

The AD9776/AD9778/AD9779 are dual, 12-/14-/16-bit, high dynamic range, digital-to-analog converters (DACs) that provide a sample rate of 1 GSPS, permitting multicarrier generation up to the Nyquist frequency. They include features optimized for direct conversion transmit applications, including complex digital modulation, and gain and offset compensation. The DAC outputs are optimized to interface seamlessly with analog quad-rature modulators such as the AD8349. A serial peripheral interface (SPI®) provides for programming/readback of many internal parameters. Full-scale output current can be programmed over a range of 10 mA to 30 mA. The devices are manufactured on an advanced 0.18 μm CMOS process and operate on 1.8 V and 3.3 V supplies for a total power consumption of 1.0 W. They are enclosed in 100-lead TQFP packages.

Product Highlights

Applications

Data Sheet, Rev. A, 3/07

Features and Benefits

Low power: 1.0 W @ 1 GSPS, 600 mW @ 500 MSPS, full operating conditions
SFDR = 78 dBc to fOUT = 100 MHz
Single carrier WCDMA ACLR = 79 dBc @ 80 MHz IF
Analog output: adjustable 8.7 mA to 31.7 mA, RL = 25 Ω to 50 Ω
Novel 2×, 4×, and 8× interpolator/coarse complex modulator allows carrier placement anywhere in DAC bandwidth

Auxiliary DACs allow control of external VGA and offset control
Multiple chip synchronization interface
High performance, low noise PLL clock multiplier
Digital inverse sinc filter
100-lead, exposed paddle TQFP package

Digital to Analog Converters

D/A Converters

AD9778 IBIS Models

AD9778 IBIS Models .IBS

Data Sheets

Document	note
AD9776/AD9778/AD9779: Dual 12-/14-/16-Bit, 1 GSPS, Digital-to-Analog Converters Data Sheet (Rev. A)	PDF 1525 kB

Application Notes

Document	note
AN-748: Set-Up and Hold Measurements in High Speed CMOS Input DACs (Rev. 0)	PDF 812 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 1	PDF 1295 kB

Order Information

Part Number	Package	Packing Qty	Temp Range	Price 100-499	Price 1000+	RoHS
AD9778BSVZ Production	100 ld TQFP-ED(w/ 6.5mm exposed pad)	OTH 90	-40 to 85C	29.7	25.25	Y
AD9778BSVZRL Production	100 ld TQFP-ED(w/ 6.5mm exposed pad)	REEL 1000	-40 to 85C	0	25.25	Y