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Details, datasheet, quote on part number:AD9765AST
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Datasheet text preview:
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FEATURES 12-Bit Dual Transmit DAC 125 MSPS Update Rate Excellent SFDR to Nyquist @ 5 MHz Output: 75 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 Single 5 V or 3 V Supply Operation Power Dissipation: 380 mW @ 5 V Power-Down Mode: 50 mW @ 5 V 48-Lead LQFP APPLICATIONS Communications Base Stations Digital Synthesis Quadrature Modulation PRODUCT DESCRIPTION
12-Bit, 125 MSPS Dual TxDAC+® D/A Converter AD97651
FUNCTIONAL BLOCK DIAGRAM
DVDD DCOM AVDD ACOM CLK1 "1" DAC IOUTA1 IOUTB1 REFIO FSADJ1 FSADJ2 GAINCTRL SLEEP IOUTA2 IOUTB2 PORT1 "1" LATCH
WRT1 WRT2
REFERENCE DIGITAL INTERFACE
AD9765
BIAS GENERATOR
PORT2
"2" LATCH MODE
"2" DAC CLK2
The AD9765 is a dual port, high speed, two channel, 12-bit CMOS DAC. It integrates two high quality 12-bit TxDAC+ cores, a voltage reference and digital interface circuitry into a small 48-lead LQFP package. The AD9765 offers exceptional ac and dc performance while supporting update rates up to 125 MSPS. The AD9765 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 AD9765 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.2 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
TxDAC+ is a registered trademark of Analog Devices, Inc. 1 Patent pending. 2 Please see GAINCTRL Mode section, for important date code information on this feature.
and provide a nominal full-scale current of 20 mA. The fullscale currents between each DAC are matched to within 0.1%. The AD9765 is manufactured on an advanced low cost CMOS process. It operates from a single supply of 3.0 V to 5.0 V and consumes 380 mW of power.
PRODUCT HIGHLIGHTS
1. The AD9765 is a member of a pin-compatible family of dual TxDACs providing 8-, 10-, 12-, and 14-bit resolution. 2. Dual 12-Bit, 125 MSPS DACs: A pair of high performance DACs optimized for low distortion performance provide for flexible transmission of I and Q information. 3. Matching: Gain matching is typically 0.1% of full scale, and offset error is better than 0.02%. 4. Low Power: Complete CMOS Dual DAC function operates on 380 mW from a 3.0 V to 5.0 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. 5. On-Chip Voltage Reference: The AD9765 includes a 1.20 V temperature-compensated bandgap voltage reference. 6. Dual 12-Bit Inputs: The AD9765 features a flexible dualport interface allowing dual or interleaved input data.
REV. B
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781/329-4700 World Wide Web Site: http://www.analog.com Fax: 781/326-8703 © Analog Devices, Inc., 2000
AD9765SPECIFICATIONS
DC SPECIFICATIONS (T
Parameter RESOLUTION DC ACCURACY Integral Linearity Error (INL) TA = +25°C TMIN to TMAX Differential Nonlinearity (DNL) TA = +25°C TMIN to TMAX ANALOG OUTPUT Offset Error Gain Error (Without Internal Reference) Gain Error (With Internal Reference) Gain Match Full-Scale Output Current2 Output Compliance Range Output Resistance Output Capacitance REFERENCE OUTPUT Reference Voltage Reference Output Current3 REFERENCE INPUT Input Compliance Range Reference Input Resistance Small Signal Bandwidth TEMPERATURE COEFFICIENTS Offset Drift Gain Drift (Without Internal Reference) Gain Drift (With Internal Reference) Reference Voltage Drift POWER SUPPLY Supply Voltages AVDD DVDD Analog Supply Current (IAVDD) Digital Supply Current (IDVDD)4 Digital Supply Current (IDVDD)5 Supply Current Sleep Mode (IAVDD) Power Dissipation4 (5 V, IOUTFS = 20 mA) Power Dissipation5 (5 V, IOUTFS = 20 mA) Power Dissipation6 (5 V, IOUTFS = 20 mA) Power Supply Rejection Ratio7--AVDD Power Supply Rejection Ratio7--DVDD OPERATING RANGE
1
MIN
to TMAX, AVDD = +5 V, DVDD = +5 V, IOUTFS = 20 mA, unless otherwise noted.)
Min 12 Typ Max Units Bits
1.5 2.0 0.75 1.0 0.02 2 5 1.6 0.14 2.0 1.0
± 0.4 ± 0.3
+1.5 +2.0 +0.75 +1.0 +0.02 +2 +5 +1.6 +0.14 20.0 +1.25
LSB LSB LSB LSB % of FSR % of FSR % of FSR % of FSR dB mA V k pF V nA V M MHz ppm of FSR/°C ppm of FSR/°C ppm of FSR/°C p p m /° C
± 0.25 ±1 0.1
100 5 1.14 1.20 100 1.26
0.1 1 0.5 0 ± 50 ± 100 ± 50
1.25
3 2.7
5 5 71 5 8 380 420 450
5.5 5.5 75 7 15 12.0 410 450 +0.4 +0.025 +85
0.4 0.025 40
V V mA mA mA mA mW mW mW % of FSR/V % of FSR/V °C
NOTES 1 Measured at I OUTA, driving a virtual ground. 2 Nominal full-scale current, I OUTFS, is 32 times the I REF current. 3 An external buffer amplifier with input bias current <100 nA should be used to drive any external load. 4 Measured at f CLOCK = 25 MSPS and fOUT = 1.0 MHz. 5 Measured at f CLOCK = 100 MSPS and f OUT = 1 MHz. 6 Measured as unbuffered voltage output with I OUTFS = 20 mA and 50 RLOAD at IOUTA and IOUTB, fCLOCK = 100 MSPS and f OUT = 40 MHz. 7 ± 10% Power supply variation. Specifications subject to change without notice.
2
REV. B
DYNAMIC SPECIFICATIONS Transformer Coupled Output, 50
Parameter DYNAMIC PERFORMANCE Maximum Output Update Rate (fCLOCK) Output Settling Time (tST) (to 0.1%)1 Output Propagation Delay (tPD) Glitch Impulse Output Rise Time (10% to 90%)1 Output Fall Time (90% to 10%)1 Output Noise (IOUTFS = 20 mA) Output Noise (IOUTFS = 2 mA) AC LINEARITY Spurious-Free Dynamic Range to Nyquist fCLOCK = 100 MSPS; fOUT = 1.00 MHz 0 dBFS Output 6 dBFS Output 12 dBFS Output 18 dBFS Output fCLOCK = 65 MSPS; fOUT = 1.00 MHz fCLOCK = 65 MSPS; fOUT = 2.51 MHz fCLOCK = 65 MSPS; fOUT = 5.02 MHz fCLOCK = 65 MSPS; fOUT = 14.02 MHz fCLOCK = 65 MSPS; fOUT = 25 MHz fCLOCK = 125 MSPS; fOUT = 25 MHz fCLOCK = 125 MSPS; fOUT = 40 MHz Spurious-Free Dynamic Range Within a Window fCLOCK = 100 MSPS; fOUT = 1.00 MHz; 2 MHz Span fCLOCK = 50 MSPS; fOUT = 5.02 MHz; 10 MHz Span fCLOCK = 65 MSPS; fOUT = 5.03 MHz; 10 MHz Span fCLOCK = 125 MSPS; fOUT = 5.04 MHz; 10 MHz Span Total Harmonic Distortion fCLOCK = 100 MSPS; fOUT = 1.00 MHz fCLOCK = 50 MSPS; fOUT = 2.00 MHz fCLOCK = 125 MSPS; fOUT = 4.00 MHz fCLOCK = 125 MSPS; fOUT = 10.00 MHz Multitone Power Ratio (Eight Tones at 110 kHz Spacing) fCLOCK = 65 MSPS; fOUT = 2.00 MHz to 2.99 MHz 0 dBFS Output 6 dBFS Output 12 dBFS Output 18 dBFS Output Channel Isolation fCLOCK = 125 MSPS; fOUT = 10 MHz fCLOCK = 125 MSPS; fOUT = 40 MHz
NOTES 1 Measured single-ended into 50 load. Specifications subject to change without notice.
(TMIN to TMAX, AVDD = +5 V, DVDD = +5 V, IOUTFS = 20 mA, Differential Doubly Terminated, unless otherwise noted.)
Min 125 35 1 5 2.5 2.5 50 30 Typ Max
AD9765
Units MSPS ns ns pV-s ns ns pA/ Hz pA/ Hz
70
81 77 72 70 81 79 78 68 55 67 60 90 88 88 88 80 78 75 75 70
dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc dBc
80
80 79 77 75 85 77
dBc dBc dBc dBc dBc dBc
REV. B
3
AD9765SPECIFICATIONS
DIGITAL SPECIFICATIONS (T
Parameter DIGITAL INPUTS Logic "1" Voltage @ DVDD = +5 V Logic "1" @ DVDD = 3 Logic "0" Voltage @ DVDD = +5 V Logic "0" @ DVDD = 3 Logic "1" Current Logic "0" Current Input Capacitance Input Setup Time (tS) Input Hold Time (tH) Latch Pulsewidth (tLPW, tCPW)
Specifications subject to change without notice.
MIN
to TMAX, AVDD = +5 V, DVDD = +5 V, IOUTFS = 20 mA, unless otherwise noted.)
Min 3.5 2.1 0 10 10 5 2.0 1.5 3.5 Typ 5 3 0 Max Units V V V V µA µA pF ns ns ns
1.3 0.9 +10 +10
ABSOLUTE MAXIMUM RATINGS*
Parameter AVDD DVDD ACOM AVDD MODE, CLK1, CLK2, WRT1, WRT2 Digital Inputs I O U T A 1 / I O U T A 2 , I O U T B 1/ I O U T B 2 REFIO, FSADJ1, FSADJ2 GAINCTRL, SLEEP Junction Temperature Storage Temperature Lead Temperature (10 sec)
With Respect to ACOM DCOM DCOM DVDD DCOM DCOM ACOM ACOM ACOM
Min 0.3 0.3 0.3 6.5 0.3 0.3 1.0 0.3 0.3 65
Max +6.5 +6.5 +0.3 +6.5 DVDD + 0.3 DVDD + 0.3 AVDD + 0.3 AVDD + 0.3 AVDD + 0.3 +150 +150 +300
Units V V V V V V V V V °C °C °C
*Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum ratings for extended periods may affect device reliability.
ORDERING GUIDE
tS
tH
Model AD9765AST AD9765-EB
Temperature Range 40°C to +85°C
Package Description
Package Option*
DATA IN
(WRT2) (WRT1 / IQWRT)
48-Lead LQFP ST-48 Evaluation Board
t LPW t CPW
(CLK2) (CLK1/ IQCLK) IOUTA OR IOUTB
*ST = Thin Plastic Quad Flatpack.
THERMAL CHARACTERISTICS Thermal Resistance
t PD
48-Lead LQFP JA = 91°C/W
Figure 1. Timing Diagram for Dual and Interleaved Modes
See Dynamic and Digital sections for timing specifications.
CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD9765 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
WARNING!
ESD SENSITIVE DEVICE
4
REV. B
AD9765
PIN FUNCTION DESCRIPTIONS
Pin No. 112 13, 14, 35, 36 15, 21 16, 22 17 18 19 20 2334 37 38 39, 40 41 42 43 44 45, 46 47 48
Name PORT1 NC DCOM1, DCOM2 DVDD1, DVDD2 WRT1/IQWRT CLK1/IQCLK CLK2/IQRESET WRT2/IQSEL PORT2 SLEEP ACOM IOUTA2, IOUTB2 FSADJ2 GAINCTRL REFIO FSADJ1 I O U T B 1, I O U T A 1 AVDD MODE
Description Data Bits DB11P1 to DB0P1. No Connect. Digital Common. Digital Supply Voltage. Input write signal for PORT 1 (IQWRT in interleaving mode). Clock input for DAC1 (IQCLK in interleaving mode). Clock input for DAC2 (IQRESET in interleaving mode). Input write signal for PORT 2 (IQSEL in interleaving mode). Data Bits DB11P2 to DB0P2. Power-Down Control Input. Analog Common. "PORT 2" differential DAC current outputs. Full-scale current output adjust for DAC2. GAINCTRL Mode (0 = 2 resistor, 1 = 1 resistor.) Reference Input/Output. Full-scale current output adjust for DAC1. "PORT 1" differential DAC current outputs. Analog Supply Voltage. Mode Select (1 = Dual Port, 0 = Interleaved).
PIN CONFIGURATION
GAINCTRL
FSADJ1
FSADJ2
48 47 46 45 44 43 42 41 40 39 38 37
DB11-P1 (MSB) 1 DB10-P1 2 DB9-P1 3 DB8-P1 4 DB7-P1 5 DB6-P1 6 DB5-P1 7 DB4-P1 8 DB3-P1 9 DB2-P1 10 DB1-P1 11 DB0-P1 12
SLEEP
36 NC 35 NC 34 DB0-P2 33 DB1-P2 32 DB2-P2 31 DB3-P2 30 DB4-P2 29 DB5-P2 28 DB6-P2 27 DB7-P2 26 DB8-P2 25 DB9-P2
IOUTA1
IOUTB1
IOUTB2 DCOM2
IOUTA2 DVDD2
REFIO
PIN 1 IDENTIFIER
AD9765
TOP VIEW (Not to Scale)
13 14 15 16 17 18 19 20 21 22 23 24
DCOM1
DVDD1
NC
NC
ACOM DB11-P2 (MSB)
MODE
AVDD
WRT1/ IQWRT
CLK1/ IQCLK
NC = NO CONNECT
REV. B
5
CLK2/ IQRESET
WRT2/ IQSEL
DB10-P2
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