 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
AD9777 Datasheet(PDF) 4 Page - Analog Devices |
|
||||||||||||||||||||||||||||||
AD9777 Datasheet(HTML) 4 Page - Analog Devices |
|
|
4 / 60 page  AD9777 Rev. C | Page 4 of 60 GENERAL DESCRIPTION The AD97771 is the 16-bit member of the AD977x pin compatible, high performance, programmable 2×/4×/8× interpolating TxDAC+ family. The AD977x family features a serial port interface (SPI) that provides a high level of programmability, thus allowing for enhanced system level options. These options include selectable 2×/4×/8× interpola- tion filters; fS/2, fS/4, or fS/8 digital quadrature modulation with image rejection; a direct IF mode; programmable channel gain and offset control; programmable internal clock divider; straight binary or twos complement data interface; and a single- port or dual-port data interface. The selectable 2×/4×/8× interpolation filters simplify the requirements of the reconstruction filters while simultaneously enhancing the TxDAC+ family’s pass-band noise/distortion performance. The independent channel gain and offset adjust registers allow the user to calibrate LO feedthrough and sideband suppression errors associated with analog quadrature modulators. The 6 dB of gain adjustment range can also be used to control the output power level of each DAC. The AD9777 features the ability to perform fS/2, fS/4, and fS/8 digital modulation and image rejection when combined with an analog quadrature modulator. In this mode, the AD9777 accepts I and Q complex data (representing a single or multicarrier wave- form), generates a quadrature modulated IF signal along with its orthogonal representation via its dual DACs, and presents these two reconstructed orthogonal IF carriers to an analog quadrature modulator to complete the image rejection upconversion process. Another digital modulation mode (that is, the direct IF mode) allows the original baseband signal representation to be fre- quency translated such that pairs of images fall at multiples of one-half the DAC update rate. The AD977x family includes a flexible clock interface accepting differential or single-ended sine wave or digital logic inputs. An internal PLL clock multiplier is included and generates the necessary on-chip high frequency clocks. It can also be disabled to allow the use of a higher performance external clock source. An internal programmable divider simplifies clock generation in the converter when using an external clock source. A flexible data input interface allows for straight binary or twos comple- ment formats and supports single-port interleaved or dual-port data. Dual high performance DAC outputs provide a differential current output programmable over a 2 mA to 20 mA range. The AD9777 is manufactured on an advanced 0.35 micron CMOS process, operates from a single-supply of 3.1 V to 3.5 V, and consumes 1.2 W of power. 1 Protected by U.S. Patent Numbers, 5,568,145; 5,689,257; and 5,703,519. Other patents pending. Targeted at wide dynamic range, multicarrier, and multistandard systems, the superb baseband performance of the AD9777 is ideal for wideband CDMA, multicarrier CDMA, multicarrier TDMA, multicarrier GSM, and high performance systems employing high-order QAM modulation schemes. The image rejection feature simplifies and can help to reduce the number of signal band filters needed in a transmit signal chain. The direct IF mode helps to eliminate a costly mixer stage for a variety of communications systems. PRODUCT HIGHLIGHTS 1. The AD9777 is the 16-bit member of the AD977x pin compatible, high performance, programmable 2×/4×/8× interpolating TxDAC+ family. 2. Direct IF transmission is possible for 70 MHz + IFs through a novel digital mixing process. 3. fS/2, fS/4, and fS/8 digital quadrature modulation and user selectable image rejection simplify/remove cascaded SAW filter stages. 4. A 2×/4×/8× user selectable interpolating filter eases data rate and output signal reconstruction filter requirements. 5. User selectable twos complement/straight binary data coding. 6. User programmable channel gain control over 1 dB range in 0.01 dB increments. 7. User programmable channel offset control ±10% over the FSR. 8. Ultrahigh speed 400 MSPS DAC conversion rate. 9. Internal clock divider provides data rate clock for easy interfacing. 10. Flexible clock input with single-ended or differential input, CMOS, or 1 V p-p LO sine wave input capability. 11. Low power: Complete CMOS DAC operates on 1.2 W from a 3.1 V to 3.5 V single supply. The 20 mA full-scale current can be reduced for lower power operation, and several sleep functions are provided to reduce power during idle periods. 12. On-chip voltage reference: The AD9777 includes a 1.20 V temperature compensated band gap voltage reference. 13. An 80-lead thin quad flat package, exposed pad (TQFP_EP). |
Similar Part No. - AD9777_15 |
|
Similar Description - AD9777_15 |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
