background image

 

CMOS 300 MSPS Quadrature

Complete DDS

  

AD9854

 

 

Rev. E 

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. 

 

 
 
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700 

www.analog.com

 

Fax: 781.461.3113 

©2002–2007 Analog Devices, Inc. All rights reserved. 

FEATURES 

300 MHz internal clock rate 
FSK, BPSK, PSK, chirp, AM operation 
Dual integrated 12-bit digital-to-analog converters (DACs) 
Ultrahigh speed comparator, 3 ps rms jitter 
Excellent dynamic performance 

80 dB SFDR at 100 MHz (±1 MHz) A

OUT

 

4× to 20× programmable reference clock multiplier 
Dual 48-bit programmable frequency registers 
Dual 14-bit programmable phase offset registers 
12-bit programmable amplitude modulation and  

on/off output shaped keying function 

Single-pin FSK and BPSK data interfaces 
PSK capability via input/output interface 
Linear or nonlinear FM chirp functions with single-pin 

frequency hold function 

Frequency-ramped FSK 
<25 ps rms total jitter in clock generator mode 
 

Automatic bidirectional frequency sweeping 
Sin(x)/x correction 
Simplified control interfaces 

10 MHz serial 2- or 3-wire SPI compatible  
100 MHz parallel 8-bit programming 

3.3 V single supply 
Multiple power-down functions 
Single-ended or differential input reference clock 
Small, 80-lead LQFP or TQFP with exposed pad  

APPLICATIONS 

Agile, quadrature LO frequency synthesis 
Programmable clock generators 
FM chirp source for radar and scanning systems 
Test and measurement equipment 
Commercial and amateur RF exciters 
 

FUNCTIONAL BLOCK DIAGRAM 

DIGITAL MULTIPLIERS

SYSTEM

CLOCK

DAC R

SET

INV

SINC

FILTER

FR

E

Q

U

E

N

C

Y

A

C

C

UMUL

A

T

O

R

AC

C 1

I/O PORT BUFFERS

COMPARATOR

PROGRAMMING REGISTERS

DIFF/SINGLE

SELECT

REFERENCE

CLOCK IN

FSK/BPSK/HOLD

DATA IN

BIDIRECTIONAL

INTERNAL/EXTERNAL

I/O UPDATE CLOCK

READ

WRITE

SERIAL/

PARALLEL

SELECT

6-BIT ADDRESS

OR SERIAL

PROGRAMMING

LINES

8-BIT

PARALLEL

LOAD

MASTER

RESET

+V

S

GND

CLOCK

OUT

ANALOG

IN

OSK

ANALOG

OUT

ANALOG

OUT

P

HAS

E

-T

O

-

A

M

P

LITU

D

E

CO

NV

E

RT

E

R

PROGRAMMABLE

AMPLITUDE AND

RATE CONTROL

D

Q

CK

÷2

INT

EXT

SYSTEM

CLOCK

REF

CLK

BUFFER

SYSTEM

CLOCK

MUX

DELTA

FREQUENCY

RATE TIMER

SYSTEM

CLOCK

DELTA

FREQUENCY

WORD

FREQUENCY

TUNING

WORD 1

FREQUENCY

TUNING

WORD 2

FIRST 14-BIT

PHASE/OFFSET

WORD

SECOND 14-BIT

PHASE/OFFSET

WORD

12-BIT DC

CONTROL

MUX

SYSTEM CLOCK

P

HAS

E

A

CCUM

UL

AT

O

R

ACC

 2

DDS CORE

12-BIT

I

DAC

12-BIT

Q DAC OR

CONTROL

DAC

I

Q

12

MUX

MUX

MU

X

MUX

SYSTEM

CLOCK

SYSTEM

CLOCK

48

48

48

14

14

BUS

12

12

14

17

17

48

48

48

AD9854

MODE SELECT

2

3

DE

M

UX

MU

X

MUX

12

INV

SINC

FILTER

12

12

12

12

I AND Q 12-BIT

AM MODULATION

0

06

36-

001

4× TO 20×

REF CLK

MULTIPLIER

INTERNAL

PROGRAMMABLE

UPDATE CLOCK

 

Figure 1. 

Содержание AD9854

Страница 1: ...rrection Simplified control interfaces 10 MHz serial 2 or 3 wire SPI compatible 100 MHz parallel 8 bit programming 3 3 V single supply Multiple power down functions Single ended or differential input...

Страница 2: ...rol DAC 30 Inverse Sinc Function 31 REFCLK Multiplier 31 Programming the AD9854 32 MASTER RESET 32 Parallel I O Operation 34 Serial Port I O Operation 34 General Operation of the Serial Interface 36 I...

Страница 3: ...le Tone Mode 000 Section 17 Changes to Ramped FSK Mode 010 Section 18 Changes to Basic FM Chirp Programming Steps Section 23 Changes to Figure 50 27 Changes to Evaluation Board Operating Instructions...

Страница 4: ...used for phase changes The 12 bit I and Q DACs coupled with the innovative DDS architecture provide excellent wideband and narrow band output SFDR The Q DAC can also be configured as a user programma...

Страница 5: ...C IV 1 1 V DAC STATIC OUTPUT CHARACTERISTICS Output Update Speed Full I 300 200 MSPS Resolution 25 C IV 12 12 Bits I and Q Full Scale Output Current 25 C IV 5 10 20 5 10 20 mA I and Q DAC DC Gain Imb...

Страница 6: ...C IV 10 10 SYSCLK cycles COMPARATOR INPUT CHARACTERISTICS Input Capacitance 25 C V 3 3 pF Input Resistance 25 C IV 500 500 k Input Current 25 C I 1 5 1 5 A Hysteresis 25 C IV 10 20 10 20 mV p p COMPA...

Страница 7: ...et square or sine wave centered at one half the applied VDD or a 3 V TTL level pulse input 2 An internal 400 mV p p differential voltage swing equates to 200 mV p p applied to both REFCLK input pins 3...

Страница 8: ...EDEC test board 3 Values of JA are provided for package comparison and PCB design considerations 4 Per JEDEC JESD51 6 heat sink soldered to PCB 5 Airflow increases heat dissipation effectively reducin...

Страница 9: ...7 28 72 75 to 78 DGND Connections for the Digital Circuitry Ground Return Same potential as AGND 13 35 57 58 63 NC No Internal Connection 14 to 16 A5 to A3 Parallel Address Inputs for Program Register...

Страница 10: ...ternal high speed comparator 43 VINN Voltage Input Negative The inverting input of the internal high speed comparator 48 IOUT1 Unipolar Current Output of I or the Cosine DAC Refer to Figure 3 49 IOUT1...

Страница 11: ...THE OUTPUT VOLTAGE COMPLIANCE RATING COMPARATOR OUT AVDD DVDD DIGITAL IN AVOID OVERDRIVING DIGITAL INPUTS FORWARD BIASING ESD DIODES MAY COUPLE DIGITAL NOISE ONTO POWER PINS A DAC OUTPUTS B COMPARATO...

Страница 12: ...0636 004 Figure 4 Wideband SFDR 19 1 MHz 0 START 0Hz 10 20 30 40 50 60 70 80 90 100 15MHz STOP 150MHz 00636 005 Figure 5 Wideband SFDR 39 1 MHz 0 START 0Hz 10 20 30 40 50 60 70 80 90 100 15MHz STOP 15...

Страница 13: ...d SFDR 39 1 MHz 1 MHz BW 300 MHz REFCLK with REFCLK Multiplier Bypassed 0 CENTER 39 1MHz 10 20 30 40 50 60 70 80 90 100 5kHz SPAN 50kHz 00636 011 Figure 11 Narrow Band SFDR 39 1 MHz 50 kHz BW 300 MHz...

Страница 14: ...lier 10 100 110 150 120 130 140 160 170 PHASE NOISE dBc Hz AOUT 80MHz AOUT 5MHz FREQUENCY Hz 10 1M 100 100k 10k 1k 00636 018 Figure 18 Residual Phase Noise 300 MHz REFCLK with REFCLK Multiplier Bypass...

Страница 15: ...itter 40 MHz AOUT 300 MHz RFCLK with REFCLK Multiplier Bypassed CH1 500mV M 500ps CH1 980mV REF1 RISE 1 174ns C1 FALL 1 286ns 00636 023 Figure 23 Comparator Rise Fall Times FREQUENCY MHz 1200 0 AMPLIT...

Страница 16: ...8 10 BIT ADC DIGITAL DEMODULATOR Rx BASEBAND DIGITAL DATA OUT 8 8 I Q MIXER AND LOW PASS FILTER VCA ADC ENCODE ADC CLOCK FREQUENCY LOCKED TO Tx CHIP SYMBOL PN RATE REFERENCE CLOCK 48 CHIP SYMBOL PN RA...

Страница 17: ...0 8 TO 2 5GHz AD9854 QUADRATURE DDS DDS LO LO DDS LO 36dB TYPICAL SSB REJECTION 50 VOUT AD8346 QUADRATURE MODULATOR 90 COSINE DC TO 70MHz SINE DC TO 70MHz LO LO 0 00636 031 NOTES 1 FLIP DDS QUADRATURE...

Страница 18: ...I DAC 1 2 Q DAC OR CONTROL DAC LOW PASS FILTER LOW PASS FILTER 00636 034 NOTES 1 IOUT APPROX 20mA MAX WHEN RSET 2k 2 SWITCH POSITION 1 PROVIDES COMPLEMENTARY SINUSOIDAL SIGNALS TO THE COMPARATOR TO PR...

Страница 19: ...1 1 Chirp 1 0 0 BPSK In each mode some functions may be prohibited Table 6 lists the functions and their availability for each mode Single Tone Mode 000 This is the default mode when the MASTER RESET...

Страница 20: ...ated via the 8 bit parallel programming port at a 100 MHz parallel byte rate or at a 10 MHz serial rate Incorporating this attribute permits FM AM PM FSK PSK and ASK operation in single tone mode Unra...

Страница 21: ...raditional FSK Mode I O UD CLK F1 F2 0 FREQUENCY MODE TW1 TW2 010 RAMPED FSK F1 F2 000 DEFAULT 0 0 REQUIRES A POSITIVE TWOS COMPLEMENTVALUE RAMP RATE DFW FSK DATA PIN 29 00636 037 Figure 37 Ramped FSK...

Страница 22: ...ter is activated when a logic level change occurs on the FSK input Pin 29 This counter is run at the system clock rate 300 MHz maximum The time period between each output pulse is given as N 1 System...

Страница 23: ...dwell times at every frequency Use this function to automatically sweep between any two frequencies from dc to Nyquist In the ramped FSK mode with the triangle bit set high an automatic frequency swe...

Страница 24: ...trol bit Register Address 1F hex is available to clear both the frequency accumulator ACC1 and the phase accumulator ACC2 When this bit is set high the output of the phase accumulator results in 0 Hz...

Страница 25: ...0 Hz When the CLR ACC1 bit Register Address 1F hex is set high the 48 bit frequency accumulator ACC1 output is cleared with a retriggerable one shot pulse of one system clock duration The 48 bit delt...

Страница 26: ...F1 000 DEFAULT 0 RAMP RATE RAMP RATE 011 CHIRP DELTA FREQUENCY WORD CLR ACC1 00636 045 Figure 45 Effect of CLR ACC1 in FM Chirp Mode CLR ACC2 F1 0 FREQUENCY MODE TW1 DPW 000 DEFAULT 0 RAMP RATE 011 CH...

Страница 27: ...ange between dc and Nyquist Unless terminated by the user the chirp continues until power is removed When the chirp destination frequency is reached the user can choose any of the following actions St...

Страница 28: ...solution to achieve the proper frequency range BPSK Mode 100 Binary biphase or bipolar phase shift keying is a means to rapidly select between two preprogrammed 14 bit output phase offsets that equall...

Страница 29: ...ansferring This is an effect of the minimum high pulse time when I O UD CLK functions as an output ON OFF OUTPUT SHAPED KEYING OSK The on off OSK feature allows the user to control the amplitude vs ti...

Страница 30: ...in 56 These are current output DACs with a full scale maximum output of 20 mA however a nominal 10 mA output current provides the best spurious free dynamic range SFDR performance The value of RSET is...

Страница 31: ...in 61 provides the connection for the external zero compensation network of the PLL loop filter The zero compensation network consists of a 1 3 k resistor in series with a 0 01 F capacitor The other s...

Страница 32: ...rt after the contents of the buffer memory are transferred to the register banks This transfer of information occurs synchronously to the system clock in one of two ways Internally at a rate programma...

Страница 33: ...lta frequency word 23 16 00 14 Delta frequency word 15 8 00 15 Delta frequency word 7 0 00 16 5 Update clock 31 24 00 17 Update clock 23 16 00 18 Update clock 15 8 00 19 Update clock 7 0 40 1A 6 Ramp...

Страница 34: ...and can be configured as a single pin I O SDIO or two unidirectional pins for input and output SDIO SDO Data transfers are supported in MSB or the LSB first format for up to 10 MHz When configured fo...

Страница 35: ...36 052 Figure 52 Parallel Port Read Timing Diagram D 7 0 D1 D2 D3 SPECIFICATION VALUE DESCRIPTION tASU tDSU tADH tDHD 8 0ns 3 0ns ADDRESS SETUP TIME TO WR SIGNAL ACTIVE DATA SETUP TIME TO WR SIGNAL AC...

Страница 36: ...controller expects the subsequent eight rising SCLK edges to be the instruction byte of the next communication cycle In addition an active high input on the IO RESET pin immediately terminates the cu...

Страница 37: ...yte NOTES ON SERIAL PORT OPERATION The AD9854 serial port configuration bits reside in Bit 1 and Bit 0 of Register Address 20 hex It is important to note that the configuration changes immediately upo...

Страница 38: ...the clocks are forced to dc effectively powering down the digital section In this state the PLL still accepts the REFCLK signal and continues to output the higher frequency CR 23 is reserved Write to...

Страница 39: ...n is configured as an input CR 7 is reserved Write to 0 CR 6 is the inverse sinc filter bypass bit When this bit is set the data from the DDS block goes directly to the output shaped keying logic and...

Страница 40: ...convenience can be the ground plane Sockets for either package style of the device are not recommended JUNCTION TEMPERATURE CONSIDERATIONS The power dissipation PDISS of the AD9854 in a given applica...

Страница 41: ...ed operating temperature for the AD9854 in a given application Subtract this value from 150 C which is the maximum junction temperature allowed for the AD9854 For the extended industrial temperature r...

Страница 42: ...Windows 95 Windows 98 Windows 2000 Windows NT and Windows XP Connect a printer cable from the PC to the AD9854 evaluation board printer port connector labeled J11 Hardware Preparation Use the schemat...

Страница 43: ...Q signals appear as nearly pure sine waves and 90 out of phase with each other These filters are designed with the assumption that the system clock speed is at or near its maximum speed 300 MHz If the...

Страница 44: ...al entries such as frequency and phase infor mation require pressing Enter to register the information For example if a new frequency is input but does not take effect when Load is clicked the user pr...

Страница 45: ...06CG120J9B200 10 2 C34 C43 Capacitor 1206 1206 8 2 pF 50 V NPO 0 5 pF Yageo Corporation CC1206DRNPO9BN8R2 11 9 J1 J2 J3 J4 J5 J6 J7 J25 J26 SMB STR PC MNT N A N A Emerson Johnson 131 3701 261 12 1 J10...

Страница 46: ...5552742 1 31 6 W1 W2 W3 W4 W8 W17 3 pin header SIP 3P N A N A Samtec Inc TSW 103 07 S S 32 10 W6 W7 W9 W10 W11 W12 W13 W14 W15 W16 2 pin header SIP 2P N A N A Samtec Inc TSW 102 07 S S 33 6 W1 W2 W3 W...

Страница 47: ...F C27 0 1 F C8 0 1 F C44 0 1 F GND DVDD J10 1 2 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 ADR5 ADR4 ADR3 ADR2 ADR1 ADR0 UDCLK WR RD PMO...

Страница 48: ...CC 20 RESET UDCLK PMODE ORAMP FDATA U4 74HC125D GND 1G 1A 1Y 2G 2A 2Y VCC 4G 4A 4Y 3G 3A 3Y U2 GND 1 2 3 4 5 6 7 13 12 11 10 9 8 14 VCC VCC U10 W11 ADDR1 ADDR0 W14 W12 W13 W9 VCC R18 10k GND W15 VCC R...

Страница 49: ...AD9854 Rev E Page 49 of 52 00636 070 Figure 66 Assembly Drawing 00636 071 Figure 67 Top Routing Layer Layer 1...

Страница 50: ...AD9854 Rev E Page 50 of 52 00636 072 Figure 68 Power Plane Layer Layer 3 00636 073 Figure 69 Ground Plane Layer Layer 2...

Страница 51: ...AD9854 Rev E Page 51 of 52 00636 074 Figure 70 Bottom Routing Layer Layer 4...

Страница 52: ...ITY VIEW A ROTATED 90 CCW SEATING PLANE 7 3 5 0 61 60 1 80 20 41 21 40 VIEW A 1 60 MAX 0 75 0 60 0 45 16 20 16 00 SQ 15 80 14 20 14 00 SQ 13 80 0 65 BSC LEAD PITCH 0 38 0 32 0 22 TOP VIEW PINS DOWN PI...

Отзывы: