Document
DAC908
DAC908
DAC908
SBAS109B – JUNE 2003
TM 8-Bit, 165MSPS DIGITAL-TO-ANALOG CONVERTER
FEATURES
q SINGLE +5V OR +3V OPERATION q HIGH SFDR: 5.04MHz Output at 100MSPS: 67dBc q LOW GLITCH: 3pV-s q LOW POWER: 170mW at +5V q INTERNAL REFERENCE:
Optional Ext. Reference Adjustable Full-Scale Range Multiplying Option
APPLICATIONS
q MEDICAL INSTRUMENTATION Ultrasound (DBF)
q VIDEO, DIGITAL TV q WAVEFORM GENERATION
Direct Digital Synthesis (DDS) Arbitrary Waveform Generation (ARB) q TEST INSTRUMENTATION q COMMUNICATIONS
DESCRIPTION
The DAC908 is a high-speed, Digital-to-Analog Converter (DAC) offering an 8-bit resolution option within the SpeedPlus family of high-performance converters. Featuring pin compatibility among family members, the DAC900, DAC902, and DAC904 provide a component selection option to an 10-, 12-, and 14-bit resolution, respectively. All models within this family of DACs support update rates in excess of 165MSPS with excellent dynamic performance, and are especially suited to fulfill the demands of a variety of applications.
The advanced segmentation architecture of the DAC908 is optimized to provide a high Spurious-Free Dynamic Range (SFDR) for single-tone, as well as for multi-tone signals—essential when used for the transmit signal path of communication systems.
The DAC908 has a high impedance (200kΩ) current output with a nominal range of 20mA and an output compliance of up to 1.25V. The differential outputs allow for both a differential or singleended analog signal interface. The close matching of the current outputs ensures superior dynamic performance in the differential configuration, which can be implemented with a transformer.
Utilizing a small geometry CMOS process, the monolithic DAC908 can be operated on a wide, single-supply range of +2.7V to +5.5V. Its low power consumption allows for use in portable and batteryoperated systems. Further optimization can be realized by lowering the output current with the adjustable full-scale option.
For noncontinuous operation of the DAC908, a power-down mode results in only 45mW of standby power.
The DAC908 comes with an integrated 1.24V bandgap reference and edge-triggered input latches, offering a complete converter solution. Both +3V and +5V CMOS logic families can be interfaced to the DAC908.
The reference structure of the DAC908 allows for additional flexibility by utilizing the on-chip reference, or applying an external reference. The full-scale output current can be adjusted over a span of 2mA to 20mA, with one external resistor, while maintaining the specified dynamic performance.
The DAC908 is available in the SO-28 and TSSOP-28 packages.
+VA DAC908
FSA REFIN
INT/EXT
BW +VD
Current Sources
LSB Switches
Segmented Switches
IOUT IOUT BYP
+1.24V Ref.
AGND
CLK
Latches
8-Bit Data Input D7...D0
PD DGND
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.
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Copyright © 2002-2003, Texas Instruments Incorporated
ABSOLUTE MAXIMUM RATINGS
+VA to AGND ........................................................................ –0.3V to +6V +VD to DGND ........................................................................ –0.3V to +6V AGND to DGND ................................................................. –0.3V to +0.3V
+VA to +VD ............................................................................... –6V to +6V CLK, PD to DGND ..................................................... –0.3V to VD + 0.3V D0-D7 to DGND ......................................................... –0.3V to VD + 0.3V IOUT, IOUT to AGND ........................................................ –1V to VA + 0.3V BW, BYP to AGND ..................................................... –0.3V to VA + 0.3V REFIN, FSA to AGND ................................................. –0.3V to VA + 0.3V INT/EXT to AGND ...................................................... –0.3V to VA + 0.3V Junction Temperature .................................................................... +150°C Case Temperature ......................................................................... +100°C Storage Temperature .................................................................... +125°C
ELECTROSTATIC DISCHARGE SENSITIVITY
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision inte.