Analog Devices AD9786 A Datasheet

16-Bit, 200 MSPS/500 MSPS TxDAC+® with

2×/4×/8× Interpolation and Signal Processing

FEATURES

16-bit resolution, 200 MSPS input data rate
IMD 90 dBc @10 MHz
Noise spectral density (NSD): −164 dBm/Hz @ 10 MHz
WCDMA ACLR = 80 dBc @ 40 MHz IF
DNL = ±0.3 LSB
INL = ±0.6 LSB
Selectable 2×/4×/8× interpolation filters

/2, f

/4, f

Selectable f

DAC

DAC

Single- or dual-channel signal processing
Selectable image rejection Hilbert transform
Flexible calibration engine
Direct IF transmission features
Serial control interface
Versatile clock and data interface

3.3 V-compatible digital interface
On-chip 1.2 V reference
80-lead, thermally enhanced, TQFP_EP package

APPLICATIONS

Base stations: Multicarrier WCDMA, GSM/EDGE, TD-SCDMA,

IS136, TETRA

Instrumentation

RF signal generators, arbitrary waveform generators
HDTV transmitters
Broadband wireless systems
Digital radio links
Satellite systems

/8 modulation modes

DAC

FUNCTIONAL BLOCK DIAGRAM

AD9786

PRODUCT DESCRIPTION

The AD9786 is a 16-bit, high speed, CMOS DAC with
2×/4×/8× interpolation and signal processing features tuned
for communications applications. It offers state-of-the-art
distortion and noise performance. The AD9786 was developed
to meet the demanding performance requirements of
multicarrier and third-generation base stations. The selectable
interpolation filters simplify interfacing to a variety of input
data rates while also taking advantage of oversampling
performance gains. The modulation modes allow convenient
bandwidth placement and selectable sideband suppression.

The flexible clock interface accepts a variety of input types such
as 1 V p-p sine wave, CMOS, and LVPECL in single-ended or
differential mode. Internal dividers generate the required data
rate interface clocks.

The AD9786 provides a differential current output, supporting
single-ended or differential applications; it provides a nominal
full-scale current from 10 mA to 20 mA. The AD9786 is
manufactured on an advanced, low cost, 0.25 µm CMOS process.

LATCH

P1B[15:0]

P2B[15:0]

DATACLK

CLK+
CLK–

Rev. A

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 that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.

DATA

ASSEMBLER

DATA PORT

SYNCHRONIZER

×1

LATCH

2×2×2×

f

/2

DAC

/4

f

DAC

/8

f

DAC

2×2×2×

CLOCK DISTRIBUTION AND CONTROL

Q

0

90

Q

Figure 1.

FSADJ

0

90

0

90

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone]
Fax: [phone] © 2005 Analog Devices, Inc. All rights reserved.

∆t

Re()/Im()

HILBERT

ZERO

STUFF

CALIBRATION

16-BIT DAC

www.analog.com

REFERENCE

SPI

REFIO

CIRCUITS

I

OUTA

I

OUTB

SDIO
SDO
CSB
SCLK
RESET

03152-001

AD9786

TABLE OF CONTENTS

Product Highlights ........................................................................... 3

Specifications..................................................................................... 4

DC Specifications ......................................................................... 4

Dynamic Specifications ............................................................... 5

Digital Specifications ................................................................... 6

Absolute Maximum Ratings............................................................ 7

Thermal Resistance ...................................................................... 7

ESD Caution.................................................................................. 7

Pin Configuration and Function Descriptions............................. 8

Clock .............................................................................................. 8

Analog............................................................................................ 9

Data ................................................................................................ 9

Serial Interface ............................................................................ 10

Definition of Specifications........................................................... 11

Typical Performance Characteristics ........................................... 13

MSB/LSB Transfers .................................................................... 20

Notes on Serial Port Operation ................................................ 20

Mode Control (via Serial Port)..................................................... 21

Digital Filter Specifications........................................................... 25

Digital Interpolation Filter Coefficients.................................. 25

AD9786 Clock/Data Timing..................................................... 26

Real and Complex Signals......................................................... 33

Modulation Modes..................................................................... 34

Power Dissipation....................................................................... 39

Hilbert Transform Implementation......................................... 41

Operating the AD9786 Rev F Evaluation Board........................ 45

Power Supplies............................................................................ 45

PECL Clock Driver .................................................................... 45

Data Inputs.................................................................................. 46

Serial Port.................................................................................... 46

Serial Control Interface.................................................................. 19

General Operation of the Serial Interface............................... 19

Serial Interface Port Pin Descriptions..................................... 19

REVISION HISTORY

2/05—Rev. 0 to Rev. A

Changed DRVDD Supply Range......................................Universal

Changes to DC Specifications......................................................... 4

Changes to Dynamic Specifications............................................... 5

Changes to Digital Specifications................................................... 6

Changes to Absolute Maximum Ratings....................................... 7

Change to Figure 2 ........................................................................... 8

Replaced Figure 13 .........................................................................14

Replaced Figure 14 .........................................................................14

Replaced Figure 16 .........................................................................15

Replaced Figure 21 .........................................................................16

Replaced Figure 22 .........................................................................16

Replaced Figure 26 .........................................................................16

Replaced Figure 27 .........................................................................17

Changes to Table 15........................................................................ 22

Analog Output............................................................................ 46

Outline Dimensions....................................................................... 60

Ordering Guide .......................................................................... 60

Change to Figure 44....................................................................... 26

Replaced Figure 45 ......................................................................... 26

Change to Figure 47....................................................................... 27

Change to Figure 48....................................................................... 27

Change to Figure 51....................................................................... 29

Change to Figure 52....................................................................... 29

Change to Figure 53....................................................................... 30

Change to DATAADJUST Synchronization Section................. 31

Changes to Power Dissipation Section ........................................ 40

Changes to Table 37 ....................................................................... 42

Changes to Data Inputs Section ................................................... 46

Change to Figure 88....................................................................... 49

Replaced Figure 95 ......................................................................... 55

Updated Outline Dimensions....................................................... 60

Changes to Ordering Guide.......................................................... 60

7/04—Revision 0: Initial Version

Rev. A | Page 2 of 60

AD9786

PRODUCT HIGHLIGHTS

1. The AD9786 is a 16-bit, high speed, interpolating

TxDAC+.

2. 2×/4×/8× user-selectable interpolating filter eases data rate

and output signal reconstruction filter requirements.

3. 200 MSPS input data rate.

4. Ultra high speed, 500 MSPS DAC conversion rate.

5. Flexible clock with single-ended or differential input:

CMOS, 1 V p-p sine wave, and LVPECL capability.

6. Complete CMOS DAC function operates from a 3.1 V to

3.5 V single analog (AVDD) supply, 2.5 V digital supply,
and a 3.3 V digital (DRVDD) supply. The DAC full-scale
current can be reduced for lower power operation, and a
sleep mode is provided for low power idle periods.

7. On-chip voltage reference: The AD9786 includes a

1.20 V temperature-compensated band gap voltage
reference.

8. Multichip synchronization: Multiple AD9786 DACs can be
synchronized to a single master AD9786 to ease timing
design requirements and optimize image reject transmit
performance.

Rev. A | Page 3 of 60

AD9786

SPECIFICATIONS

DC SPECIFICATIONS

T

to T

MIN

Table 1.

Parameter Min Typ Max Unit

RESOLUTION 16 Bits

DC Accuracy1

ANALOG OUTPUT

Offset Error ±0.015 ±0.0175 % of FSR

REFERENCE OUTPUT

Reference Voltage 1.15 1.23 1.30 V
Reference Output Current3 1 µA

REFERENCE INPUT

Input Compliance Range 0.1 1.25 V
Reference Input Resistance (External Reference Mode) 10 MΩ
Small Signal Bandwith 200 kHz

TEMPERATURE COEFFICIENTS

Unipolar Offset Drift 0 ppm of FSR/°C
Gain Drift (with Internal Reference) ±4 ppm of FSR/°C
Reference Voltage Drift ±30 ppm/°C

POWER SUPPLY

AVDD1, AVDD2

ACVDD, ADVDD

CLKVDD

DVDD

DRVDD

OPERATING RANGE –40 +85 °C

1

Measured at I

2

Nominal full-scale current, I

3

Use an external amplifier to drive any external load.

4

Measured under the following conditions: f

, AVDD1, AVDD2, DRVDD = 3.3 V, ACVDD, ADVDD, CLKVDD, DVDD = 2.5 V, I

MAX

= 20 mA, unless otherwise noted.

OUTFS

Integral Nonlinearity ±0.6 LSB
Differential Nonlinearity ±0.3 LSB

Gain Error (with Internal Reference) ±1.5 % of FSR
Full-Scale Output Current2 10 20 mA
Output Compliance Range –1.0 +1.0 V
Output Resistance 10 MΩ

Voltage Range 3.1 3.3 3.5 V
Analog Supply Current (I
I

+ I

AVDD1

in Sleep Mode 18 mA

AVDD2

AVDD1

+ I

) 50 mA

AVDD2

Voltage Range 2.35 2.5 2.65 V
Analog Supply Current (I

ACVDD

+ I

) 2.5 mA

ADVDD

Voltage Range 2.35 2.5 2.65 V
Clock Supply Current (I

) 12 mA

CLKVDD

Voltage Range 2.35 2.5 2.65 V
Digital Supply Current (I

) 52.5 mA

DVDD

Voltage Range 3.1 3.3 3.5 V
Digital Supply Current (I

) 5.3 µA

DRVDD

Nominal Power Dissipation4 1.25 W

driving a virtual ground.

OUTA

, is 32× the I

OUTFS

current.

REF

= 125 MSPS, f

DATA

= 500 MSPS, 4× interpolation, f

DAC

/4 modulation, Hilbert off.

DAC

Rev. A | Page 4 of 60

AD9786

DYNAMIC SPECIFICATIONS

T

to T

MIN

, AVDD1, AVDD2, DRVDD = 3.3 V, ACVDD, ADVDD, CLKVDD, DVDD = 2.5 V, I

MAX

coupled output, 50 Ω doubly terminated, unless otherwise noted.

Table 2.

Parameter Min Typ Max Unit

DYNAMIC PERFORMANCE

Minimum DAC Output Update Rate 20 MHz
Maximum DAC Output Update Rate (f

) 500 MSPS

DAC

Output Settling Time (tST) (to 0.025%) ns
Output Propagation Delay1 (tPD) ns
Output Rise Time (10% to 90% of Full Scale)2 ns
Output Fall Time (90% to 10% of Full Scale)2 ns

AC LINEARITY/BASEBAND MODE

Spurious-Free Dynamic Range (SFDR) to Nyquist (f

f

= 100 MSPS; f

DATA

f

= 200 MSPS; f

DATA

f

= 200 MSPS; f

DATA

f

= 200 MSPS; f

DATA

= 5 MHz, 4×, 2× interpolation 93 dBc

OUT

= 10 MHz 85 dBc

OUT

= 25 MHz 78 dBc

OUT

= 50 MHz 78 dBc

OUT

Two-Tone Intermodulation (IMD) to Nyquist (f

f

= 200 MSPS; f

DATA

f

= 200 MSPS; f

DATA

f

= 200 MSPS; f

DATA

f

= 200 MSPS; f

DATA

f

= 200 MSPS; f

DATA

f

= 200 MSPS; f

DATA

= 5 MHz; f

OUT1

= 15 MHz; f

OUT1

= 25 MHz; f

OUT1

= 45 MHz; f

OUT1

= 65 MHz; f

OUT1

= 85 MHz; f

OUT1

= 6 MHz 85 dBc

OUT2

= 16 MHz 85 dBc

OUT2

= 26 MHz 84 dBc

OUT2

= 46 MHz 80 dBc

OUT2

= 66 MHz 78 dBc

OUT2

= 86 MHz 75 dBc

OUT2

= 0 dBFS)

OUT

= f

OUT1

= –6 dBFS)

OUT2

Noise Power Spectral Density (NPSD)

f

= 156 MSPS; f

DATA

f

= 156 MSPS; f

DATA

= 10 MHz; 0 dBFS, 8 tones, separation = 500 kHz −164 dBm/Hz

OUT

= 50 MHz; 0 dBFS, 8 tones, separation = 500 kHz −161 dBm/Hz

OUT

Adjacent Channel Power Ratio (ACLR)
WCDMA ACLR with 3.84 MHz BW, single carrier

IF = 21 MHz, f
IF = 224.76 MHz, f

= 122.88 MSPS, 4× interpolation 80 dB

DATA

= 122.88 MSPS, 4× interpolation, high-pass interpolation filter mode 72 dB

DATA

1

Propagation delay is delay from CLK input to DAC update.

2

Measured doubly terminated into 50 Ω load.

= 20 mA, differential transformer

OUTFS

Rev. A | Page 5 of 60

AD9786

DIGITAL SPECIFICATIONS

T

to T

MIN

Table 3.

Parameter Min Typ Max Unit

DIGITAL INPUTS

Logic 1 Voltage DRVDD – 0.9 DRVDD V
Logic 0 Voltage 0 0.9 V
Logic 1 Current –10 +10 µA
Logic 0 Current –10 +10 µA
Input Capacitance 5 pF

CLOCK INPUTS1

Input Voltage Range 0 2.65 V
Common-Mode Voltage 0.75 1.5 2.25 V
Differential Voltage 0.5 1.5 V
Latch Pulse Width (t
Data Setup Time to DATACLK Out in Master Mode (tS) −0.5 ns
Data Hold Time to DATACLK Out in Master Mode (tH) 2.9 ns

1

See the AD9786 Clock/Data Timing section for setup and hold times in various timing modes.

, AVDD1, AVDD2, DRVDD = 3.3 V, ACVDD, ADVDD, CLKVDD, DVDD = 2.5 V, I

MAX

) 5 ns

LPW

= 20 mA, unless otherwise noted.

OUTFS

Rev. A | Page 6 of 60

AD9786

ABSOLUTE MAXIMUM RATINGS

Table 4.

Parameter With Respect to Min Max Unit

AVDD1, AVDD2,
DRVDD

ACVDD, ADVDD,
CLKGND, DVDD

AGND1, AGND2,
ACGND, ADGND,
CLKGND, DGND

REFIO, FSADJ AGND1 −0.3

I

, I

OUTA

P1B15 to P1B0,
P2B15 to P2B0

DATACLK DGND −0.3

CLK+, CLK−, RESET CLKGND −0.3

CSB, SCLK,
SDIO, SDO

Junction
Temperature

Storage
Temperature

Lead Temperature
(10 sec)

AGND1 −1.0

OUTB

AGND1, AGND2,
ACGND, ADGND,
CLKGND, DGND

AGND1, AGND2,
ACGND, ADGND,
CLKGND, DGND

AGND1, AGND2,
ACGND, ADGND,
CLKGND, DGND

DGND −0.3

DGND −0.3

−65 +125 °C

150 °C

300 °C

−0.3 +3.6 V

−0.3 +2.8 V

−0.3 +0.3 V

AVDD1
+ 0.3

AVDD1
+ 0.3

DRVDD
+ 0.3

DRVDD
+ 0.3

CLKVDD
+ 0.3

DRVDD
+ 0.3

V

V

V

V

V

V

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.

THERMAL RESISTANCE

80-lead thermally enhanced TQFP_EP θJA = 23.5°C/W (with
thermal pad soldered to PCB).

ESD 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 this product
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.

Rev. A | Page 7 of 60

AD9786

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

DNC

ADVDD

ADGND

ACVDD

ACGND

AVDD2

AGND2

AVDD1

AGND1

IOUTA

IOUTB

AGND1

DRVDD

DATACLK

AVDD1

IQSEL/P2B15

CLKVDD

DNC
CLKVDD
CLKGND

CLK+
CLK–

CLKGND

DGND

DVDD
P1B15
P1B14
P1B13
P1B12
P1B11
P1B10

DGND

DVDD

P1B9
P1B8
P1B7

DNC = DO NOT CONNECT

80 79 78 77 76 71 70 69 68 67 66 6575 74 73 72 64 63 62 61

1

PIN 1

2

IDENTIFIER

3
4
5
6
7
8

9
10
11
12
13
14
15
16
17
18
19
20

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

P1B6

P1B5

P1B4

P1B3

DGND

DVDD

P1B2

AD9786

TOP VIEW

(Not to Scale)

P1B1

P1B0

AGND2

AVDD2

DGND

P2B13

ACGND

ACVDD

DVDD

P2B12

ADGND

ADVDD

P2B11

P2B10

DNC

P2B9

60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41

FSADJ
REFIO
RESET
CSB
SCLK
SDIO
SDO
DGND
DVDD
P2B0
P2B1
P2B2
P2B3
P2B4
P2B5
DGND
DVDD
P2B6
P2B7
P2B8

Figure 2. Pin Configuration

CLOCK

Table 5. Clock Pin Function Descriptions

Pin
No. Mnemonic Direction Description

5, 6 CLK+, CLK– I Differential Clock Input.
2 DNC Do Not Connect.
31 DATACLK I/O

1, 3 CLKVDD Clock Domain 2.5 V.
4, 7 CLKGND Clock Domain 0 V.

DCLKEXT
0x02[3]

0

Mode

Pin configured for input of channel data rate or synchronizer clock. Internal clock
synchronizer can be turned on or off with DCLKCRC (0x02[2]).

1 Pin configured for output of channel data rate or synchronizer clock.

ONEPORTCLOCK/P2B14

03152-002

Rev. A | Page 8 of 60

AD9786

ANALOG

Table 6. Analog Pin Function Descriptions

Pin No. Mnemonic Direction Description

59 REFIO A Reference.
60 FSADJ A Full-Scale Adjust.
70, 71 IOUTB, IOUTA A Differential DAC Output Currents.
61 DNC Do Not Connect.
62, 79 ADVDD Analog Domain Digital Content 2.5 V.
63, 78 ADGND Analog Domain Digital Content 0 V.
64, 77 ACVDD Analog Domain Clock Content 2.5 V.
65, 76 ACGND Analog Domain Clock Content 0 V.
66, 75 AVDD2 Analog Domain Clock Switching 3.3 V.
67, 74 AGND2 Analog Domain Switching 0 V.
68, 73 AVDD1 Analog Domain Quiet 3.3 V.
69, 72 AGND1 Analog Domain Quiet 0 V.
80 DNC Do Not Connect.

DATA

Table 7. Data Pin Function Descriptions

Pin No. Mnemonic Direction Description

10 to 15, 18 to
24, 27 to 29

32 IQSEL/P2B15 I

33 ONEPORTCLOCK/P2B14 I/O

34, 37 to 43,
46 to 51

30 DRVDD Digital Output Pin Supply, 3.3 V.
9, 17, 26,

36, 44, 52
8, 16, 25,

35, 45, 53

P1B15 to P1B0 I

P2B13 to P2B0 I Input Data Port 2, Bit 13 to Bit 0.

DVDD Digital Domain, 2.5 V.

DGND Digital Domain, 0 V.

Input Data Port 1.

ONEPORT
0x02[6] Mode

0 Latched data routed for I channel processing.
1

ONEPORT
0x02[6]

0 X X

1 0 0

1 0 1

1 1 0

1 1 1

ONEPORT
0x02[6]

0 Latched data routed for Q channel Bit 14 processing.
1

Latched data demultiplexed by IQSEL and routed for
interleaved I/Q processing.

IQPOL
0x02[1]

Pin configured for output of clock at twice the channel
data route.

IQSEL/
P2B15 Mode (IQPOL = 0)

Latched data routed to Q channel Bit 15
(MSB) processing.

Latched data on Data Port 1 routed to Q
channel processing.

Latched data on Data Port 1 routed to I
channel processing.

Latched data on Data Port 1 routed to I
channel processing.

Latched data on Data Port 1 routed to Q
channel processing.

Rev. A | Page 9 of 60

AD9786

SERIAL INTERFACE

Table 8. Serial Interface Pin Function Descriptions

Pin No. Mnemonic Direction Description

54 SDO O

55 SDIO I/O

56 SCLK I Serial Interface Clock.
57 CSB I Serial Interface Chip Select.
58 RESET I Resets entire chip to default state.

SDIODIR
0x00[7]

CSB

1 X High impedance.
0 0 Serial data output.
0 1 High impedance.

SDIODIR

CSB

0x00[7] Mode

1 X High impedance.
0 0 Serial data output.
0 1 Serial data input/output depending on Bit 7 of the serial instruction byte.

Mode

Rev. A | Page 10 of 60

AD9786

DEFINITION OF SPECIFICATIONS

Linearity Error (Integral Nonlinearity or INL)

Linearity error is defined as the maximum deviation of the
actual analog output from the ideal output, determined by a
straight line drawn from zero to full scale.

Settling Time

The time required for the output to reach and remain within a
specified error band about its final value, measured from the
start of the output transition.

Differential Nonlinearity (DNL)

DNL is the measure of the variation in analog value, normal­ized to full scale, associated with a 1 LSB change in digital
input code.

Monotonicity

A D/A converter is monotonic if the output either increases or
remains constant as the digital input increases.

Offset Error

The deviation of the output current from the ideal of zero is
called offset error. For I
inputs are all 0s. For I

, 0 mA output is expected when the

OUTA

, 0 mA output is expected when all

OUTB

inputs are set to 1.

Gain Error

The difference between the actual and ideal output span. The
actual span is determined by the output when all inputs are set
to 1s, minus the output when all inputs are set to 0.

Output Compliance Range

The range of allowable voltage at the output of a current-output
DAC. Operation beyond the maximum compliance limits can
cause either output stage saturation or breakdown, resulting in
nonlinear performance.

Glitch Impulse

Asymmetrical switching times in a DAC give rise to undesired
output transients that are quantified by a glitch impulse. It is
specified as the net area of the glitch in pV-sec.

Spurious-Free Dynamic Range

The difference, in dB, between the rms amplitude of the output
signal and the peak spurious signal over the specified bandwidth.

Total Harmonic Distortion

THD is the ratio of the rms sum of the first six harmonic
components to the rms value of the measured fundamental. It is
expressed as a percentage or in decibels.

Signal-to-Noise Ratio (SNR)

SNR is the ratio of the rms value of the measured output signal
to the rms sum of all other spectral components below the
Nyquist frequency, excluding the first six harmonics and dc.
The value for SNR is expressed in decibels.

Interpolation Filter

If the digital inputs to the DAC are sampled at a multiple rate of

(interpolation rate), a digital filter can be constructed that has

f

DATA

a sharp transition band near f
appear around f

(output data rate) can be greatly suppressed.

DAC

/2. Images that would typically

DATA

Temp er at u re D ri ft

Temperature drift is specified as the maximum change from the
ambient (+25°C) value to the value at either T

MIN

or T

MAX

. For
offset and gain drift, the drift is reported in ppm of full-scale
range (FSR) per degree Celsius. For reference drift, the drift is
reported in ppm per degree Celsius.

Power Supply Rejection

The maximum change in the full-scale output as the supplies
are varied from minimum to maximum specified voltages.

Pass Band

Frequency band in which any input applied therein passes
unattenuated to the DAC output.

Stop-Band Rejection

The amount of attenuation of a frequency outside the pass band
applied to the DAC, relative to a full-scale signal applied at the
DAC input within the pass band.

Rev. A | Page 11 of 60

AD9786

Group Delay

Number of input clocks between an impulse applied at the
device input and peak DAC output current. A half-band FIR
filter has constant group delay over its entire frequency range

Impulse Response

Response of the device to an impulse applied to the input.

Adjacent Channel Leakage Ratio (ACLR)

A ratio in dBc between the measured power within a channel
relative to its adjacent channel.

Complex Modulation

The process of passing the real and imaginary components of a
signal through a complex modulator (transfer function = e
coswt + jsinwt) and realizing real and imaginary components
on the modulator output.

jwt

=

Hilbert Transform

A function with unity gain over all frequencies, but with a phase
shift of 90° for negative frequencies, and a phase shift of –90°
for positive frequencies. Although this function can not be
implemented ideally, it can be approximated with a short FIR
filter with enough accuracy to be very useful in single sideband
radio architectures.

Complex Image Rejection

In a traditional two-part upconversion, two images are created
around the second IF frequency. These images are redundant
and have the effect of wasting transmitter power and system
bandwidth. By placing the real part of a second complex
modulator in series with the first complex modulator, either the
upper or lower frequency image near the second IF can be
rejected.

Rev. A | Page 12 of 60

AD9786

TYPICAL PERFORMANCE CHARACTERISTICS

T

to T

MIN

, AVDD1, AVDD2, DRVDD = 3.3 V, ACVDD, ADVDD, CLKVDD, DVDD = 2.5 V, I

MAX

coupled output, 50 Ω doubly terminated, unless otherwise noted.

120

120

= 20 mA, differential transformer

OUTFS

100

80

60

SFDR (dBc)

40

20

0

Figure 3. SFDR vs. Frequency, F

120

100

80

60

SFDR (dBc)

40

–3dBFS

–6dBFS

0dBFS

FREQUENCY (MHz)

= 200 MSPS, 1× Interpolation

DATA

–6dBFS

0dBFS

–3dBFS

100

80

60

SFDR (dBc)

40

20

800 10203040506070

03152-003

0

Figure 6. SFDR vs. Frequency, F

120

100

80

60

SFDR (dBc)

40

–6dBFS

FREQUENCY (MHz)

= 200 MSPS, 2× Interpolation

DATA

–3dBFS

–6dBFS

0dBFS

0dBFS

–3dBFS

800 10203040506070

03152-006

20

0

Figure 4. SFDR vs. Frequency, F

120

100

80

60

SFDR (dBc)

40

20

0

Figure 5. SFDR vs. Frequency, F

FREQUENCY (MHz)

= 100 MSPS, 4× Interpolation

DATA

0dBFS

FREQUENCY (MHz)

= 50 MSPS, 8× Interpolation

DATA

–6dBFS

–3dBFS

20

450 5 10 15 20 25 30 35 40

03152-004

250 5 10 15 20

03152-005

0

Figure 7. SFDR vs. Frequency, F

120

100

80

60

SFDR (dBc)

40

20

0

–6dBFS

0dBFS

–3dBFS

Figure 8. SFDR vs. Frequency, F

FREQUENCY (MHz)

= 125 MSPS, 4× Interpolation

DATA

FREQUENCY (MHz)

= 62.5 MSPS, 8× Interpolation

DATA

600 1020304050

03152-007

300 5 10 15 20 25

03152-008

Rev. A | Page 13 of 60

AD9786

90

85

80

75

70

65

SFDR (dBc)

60

55

50

Figure 9. Out-of-Band SFDR, F

0dBFS

–3dBFS

F

(MHz)

OUT

= 200 MSPS, 2× Interpolation

DATA

–6dBFS

90

85

80

75

70

65

60

OUT OF BAND SFDR (dBc)

55

800 102030 607040 50

03152-009

50

010 304020

–6dBFS

ANALOG OUTPUT FREQUENCY (MHz)

Figure 12. Out-of-Band SFDR, F

0dBFS

–3dBFS

= 100 MSPS, 4× Interpolation

DATA

03152-012

100

IMD (dBc)

95

90

85

80

75

70

65

60

55

50

0dBFS

Figure 10. Out-of-Band SFDR, F

100

IMD (dBc)

95

90

85

80

75

70

65

60

55

50

–3dBFS

0dBFS

Figure 11. Out-of-Band SFDR, F

–6dBFS

–3dBFS

F

(MHz)

OUT

= 125 MSPS, 4× Interpolation

DATA

–6dBFS

F

(MHz)

OUT

= 62.5 MSPS, 8× Interpolation

DATA

90

85

80

75

–3dBFS

70

65

60

OUT OF BAND SFDR (dBc)

55

260200 220 2400 20 40 60 120 140 160 18080 100

03152-010

50

Figure 13. Out-of-Band SFDR, F

100

95

90

85

80

75

70

IMD (dBc)

65

60

55

2600 20 40 60 120 140 160 180 200 220 24080 100

03152-011

50

Figure 14. Third-Order IMD vs. Frequency, F

0dBFS

ANALOG OUTPUT FREQUENCY (MHz)

–3dBFS

–6dBFS

–6dBFS

= 50 MSPS, 8× Interpolation

DATA

0dBFS

F

(MHz)

OUT

DATA

250 5 10 15 20

03152-013

800 204060

03152-014

= 160 MSPS, 1× Interpolation

Rev. A | Page 14 of 60

AD9786

100

IMD (dBc)

95

90

85

80

75

70

65

60

55

50

–3dBFS

0dBFS

F

OUT

(MHz)

Figure 15. Third-Order IMD vs. Frequency, F

–6dBFS

1600 20 40 60 120 14080 100

= 160 MSPS, 2× Interpolation

DATA

03152-015

100

IMD (dBc)

95

90

85

80

75

70

65

60

55

50

–3dBFS

0dBFS

F

(MHz)

OUT

Figure 18. Third-Order IMD vs. Frequency, F

–6dBFS

10002040 8060

= 200 MSPS,1x Interpolation

DATA

03152-018

100

–3dBFS

0dBFS

F

OUT

(MHz)

IMD (dBc)

95

90

85

80

75

70

65

60

55

50

Figure 16. Third-Order IMD vs. Frequency, F

100

IMD (dBc)

95

90

85

80

75

70

65

60

55

50

0dBFS

F

OUT

–3dBFS

(MHz)

Figure 17. Third-Order IMD vs. Frequency, F

–6dBFS

2000 20 40 60 120 140 160 18080 100

= 200 MSPS, 2× Interpolation

DATA

–6dBFS

260200 220 2400 20 40 60 120 140 160 18080 100

= 125 MSPS, 4× Interpolation

DATA

03152-016

03152-017

100

–3dBFS

F

0dBFS

OUT

–6dBFS

(MHz)

IMD (dBc)

95

90

85

80

75

70

65

60

55

50

Figure 19. Third-Order IMD vs. Frequency, F

100

IMD (dBc)

95

90

85

80

75

70

65

60

55

50

–3dBFS

0dBFS

F

(MHz)

OUT

Figure 20. Third-Order IMD vs. Frequency, F

2000 20 40 60 120 140 160 18080 100

= 100 MSPS, 4× Interpolation

DATA

–6dBFS

2000 20 40 60 120 140 160 18080 100

= 50 MSPS, 8× Interpolation

DATA

03152-019

03152-020

Rev. A | Page 15 of 60

AD9786

100

95

90

85

80

75

70

IMD (dBc)

65

60

55

50

Figure 21. Third-Order IMD vs. Frequency, F

–3dBFS

0dBFS

F

(MHz)

OUT

–6dBFS

2600 204060 12010080 160140 180 200 220 240

= 62.5 MSPS, 8× Interpolation

DATA

03152-021

0.3

0.2

0.1

0

–0.1

DNL (LSBs)

–0.2

–0.3

–0.4

CODE

655360 8192 16384 24576 49152 5734432768 40960

03152-024

Figure 24. Typical DNL

1.25

1.00

0.75

0.50

0.25

INL (LSBs)

–0.25

–0.50

–140

–145

–150

–155

–160

–165

–170

–175

NOISE SPECTRAL DENSITY(dBm/Hz)

–180

0

CODE

Figure 22. Typical INL

F

= 156MSPS, 1× INTERPOLATION

DATA

F

= 156MSPS, 2× INTERPOLATION

DATA

ANALOG OUTPUT FREQUENCY (MHz)

Figure 23. Noise Spectral Density vs. Analog

Input Frequency, F

DATA

= 156 MSPS

–140

–145

–150

F

= 78MSPS, 1× INTERPOLATION

–155

–160

–165

–170

–175

NOISE SPECTRAL DENSITY(dBm/Hz)

655360 8192 16384 24576 49152 5734432768 40960

03152-022

–180

DATA

F

= 78MSPS, 2× INTERPOLATION

DATA

ANALOG OUTPUT FREQUENCY (MHz)

800 102030 607040 50

03152-025

Figure 25. Noise Spectral Density vs. Analog

= –6DBFS

A

IN

= 78 MSPS

DATA

800 10203040506070

03152-026

Input Frequency, F

–150

–152

–154

–156

–158

–160

AIN = 0DBFS

–162

–164

–166

NOISE SPECTRAL DENSITY (dBm/Hz)

–168

1600 20 40 60 120 14080 100

03152-023

–170

A

= –3DBFS

IN

ANALOG OUTPUT FREQUENCY (MHz)

Figure 26. Noise Spectral Density vs. Analog Input Frequency,

= 78 MSPS, 2x Interpolation

F

DATA

Rev. A | Page 16 of 60

AD9786

–

–

–150

–152

–154

A

= –3dBFS

–156

–158

–160

AIN = 0dBFS

IN

–162

= –6dBFS

A

–164

IN

–166

NOISE SPECTRAL DENSITY (dBm/Hz)

–168

–170

ANALOG OUTPUT FREQUENCY (MHz)

Figure 27. Noise Spectral Density vs. Analog Input Frequency,

= 156 MSPS, 2x Interpolation

F

DATA

–60

–65

1600 20 40 60 80 100 120 140

03152-027

10

0

–10

–20

1AVG

–30

–40

–50

–60

–70

–80

1

–90

100

–110

START 100 kHz STOP 200 MHz19.9 MHz/

Figure 30. Two Tones Around 23 MHz, F

2× Interpolation, Low-Pass Digital Filter Mode

= 200 MSPS,

DATA

1MA

03152-030

–70

–75

ACLR (dBc)

–80

0dBFS

–3dBFS

–6dBFS

–85

–90

F

(MHz)

OUT

Figure 28. ACLR for First Adjacent Band vs. Frequency,

= 61.44 MSPS, 4× Interpolation

F

DATA

–60

–65

–70

0dBFS

–75

ACLR (dBc)

–80

–85

–90

F

(MHz)

OUT

Figure 29. ACLR for First Adjacent Band vs. Frequency,

= 76.8 MSPS, 4× Interpolation

F

DATA

–6dBFS

–3dBFS

10

0

–10

–20

1AVG

–30

–40

–50

–60

–70

–80

1

–90

1500 25 50 75 100 125

03152-028

100

–110

START 100 kHz STOP 200 MHz19.9 MHz/

Figure 31. Two Tones Around 177 MHz, F

= 200 MSPS,

DATA

1MA

03152-031

2× Interpolation, High-Pass Digital Filter Mode

REF –29.82dBm
*AVG

Log
10dB/

AVERAGE
103

PAVG
22
W1 S2

CENTER 51.44MHz
*RES BW 30kHz

RMS RESULTS

CARRIER POWER

2000 20 40 60 80 100 120 140 160 180

03152-029

–17.41dBm/

3.84MHz

*ATTEN 6dB

FREQ OFFSET

5.000MHz

10.000MHz

15.000MHz

20.000MHz

REF BW

3.840MHz

3.840MHz

3.840MHz

3.840MHz

LOWER

dBc

0.15
–74.24
–75.73
–75.67

SWEEP 142.2ms (601 pts)VBW 300kHz

dBm
–17.26
–91.65
–93.14
–93.08

SPAN 43.84MHz

UPPER

dBc

dBm

–74.63

–92.05

–75.67

–93.08

–76.38

–93.79

–75.75

–93.17

03152-032

Figure 32. ACLR for Two WCDMA Carriers @ 51.44 MHz,

= 61.44 MSPS, 4× Interpolation

F

DATA

Rev. A | Page 17 of 60

AD9786

REF –22.76dBm
*AVG

Log
10dB/

AVERAGE
22

PAVG
22
W1 S2

CENTER 20.00MHz
*RES BW 30kHz

RMS RESULTS

CARRIER POWER
–10.38dBm/

3.84 MHz

Figure 33. ACLR for Single WCDMA Carrier @ 20 MHz,

*ATTEN 8dB

FREQ OFFSET

5.000MHz

10.000MHz

15.000MHz

F

REF BW

dBc

3.840MHz

–79.00

3.840MHz

–80.78

3.840MHz

–79.71

= 61.44 MSPS, 4× Interpolation

DATA

SWEEP 109.8ms (601 pts)VBW 300kHz

LOWER

dBm
–89.38
–91.16
–90.09

AC-COUPLED

SPAN 33.84MHz

UPPER

dBc

dBm

–79.63

–90.01

–81.77

–92.15

–81.45

–91.83

03152-033

REF –33.3dBm
*AVG

Log
10dB/

AVERAGE
104

PAVG
104
W1 S2

CENTER 46.40MHz
*RES BW 30kHz

RMS RESULTS

CARRIER POWER
–20.32dBm/

3.84MHz

*ATTEN 6dB

FREQ OFFSET

5.000MHz

10.000MHz

15.000MHz

20.000MHz

25.000MHz

REF BW

3.840MHz

3.840MHz

3.840MHz

3.840MHz

3.840MHz

LOWER

dBc

0.22
–0.60
–72.68
–72.74
–73.05

SWEEP 174.6ms (601 pts)VBW 300kHz

dBm
–20.11
–20.92
–93.00
–93.06
–93.37

Figure 35. ACLR for Four WCDMA Carrier Near 50 MHz,

= 61.44 MSPS, 4× Interpolation

F

DATA

AC-COUPLED

SPAN 53.84MHz

UPPER

dBc

dBm

–0.16

–20.48

–72.05

–92.37

–72.85

–93.18

–72.55

–92.88

–72.02

–92.35

03152-035

REF –28.2dBm
*AVG

Log
10dB/

AVERAGE
22

PAVG
22
W1 S2

CENTER 142.88MHz
*RES BW 30kHz

RMS RESULTS

CARRIER POWER
–15.30dBm/

3.84MHz

*ATTEN 6dB

FREQ OFFSET

5.000MHz

10.000MHz

15.000MHz

REF BW

3.840MHz

3.840MHz

3.840MHz

LOWER

dBc
–72.33
–72.41
–72.67

SWEEP 109.8ms (601 pts)VBW 300kHz

dBm
–87.64
–87.71
–87.97

Figure 34. ACLR for Single WCDMA Carrier @ 142.88 MHz,

= 61.44 MSPS, 4× Interpolation

F

DATA

SPAN 33.84MHz

UPPER

dBc

dBm

–72.13

–87.43

–73.02

–88.32

–73.50

–88.88

03152-034

Rev. A | Page 18 of 60