Analog Devices AD9912 manual

1 GSPS Direct Digi tal Synthesizer with 14 - Bit DAC AD9912 Rev. D Info rmation fu rnished by A nalog Devic es is believed to be ac curate an d reliable . Ho wev er , no respo nsibility is assumed by An alog Devices fo r its use, nor for any infringements of p atents or other rights of third parties that may resu lt from its use . Specif ications s[...]

AD9912 Rev. D | Page 2 of 40 T ABLE OF CONTENTS Fea tures .............................................................................................. 1  A pplica tions ....................................................................................... 1  General Descr iption .............................................................[...]

AD9912 Rev. D | P age 3 of 40 SPECIFICA TIONS DC SPE CIFICATI ONS A VDD = 1.8 V ± 5% , A V DD3 = 3.3 V ± 5%, DVDD = 1.8 V ± 5%, DVDD_I/O = 3.3 V ± 5% , A VSS = 0 V , D VS S = 0 V , u nless o therwise noted. Tabl e 1 . Paramet er Min Ty p Max Uni t T est Conditio ns/ Co mments SUPPL Y VOL T AGE DVDD_I/O (Pin 1) 3.135 3. 30 3.465 V DVD D ( Pin 3,[...]

AD9912 Rev. D | P age 4 of 40 Paramet er Min Ty p Max Uni t T est Conditio ns/ Co mments SYSTEM CLOCK INPU T Syste m clock in puts sho uld alwa ys be ac - coupl ed (b oth s ingl e - ended and diff erentia l) SYSCLK PLL Bypas sed In put Capaci tance 1.5 pF Sing le - ended, ea ch pin Input Resistan ce 2.4 2.6 2.9 kΩ Differ entia l Interna lly Gene [...]

AD9912 Rev. D | P age 5 of 40 AC SPECIFI CATIONS f S = 1 GHz, DA C R SET = 10 k Ω , u nless otherwis e noted . P ower suppl y pins within the range sp ecif ied in the DC Spec ifications se ctio n. Table 2 . Paramet er M in Typ Max Un it Test Conditions/Comments FDBK _IN I NPU T Pin 40, Pin 41 Input F reque ncy Range 10 400 MHz Minim um Diffe renti[...]

AD9912 Rev. D | P age 6 of 40 Paramet er M in Typ Max Un it Test Conditions/Comments CMOS Output Driver (AVDD3/Pi n 37) @ 1. 8 V Freq uency Ra nge 0.008 40 MHz See Figur e 28 f or maximum togg le rate Duty Cyc le 45 55 65 % With 20 pF load and up to 40 MHz Rise Time /Fall Ti me (20% to 80% ) 5 6.8 ns With 20 pF load DAC OUTPUT CHARAC TERISTICS DCO [...]

AD9912 Rev. D | P age 7 of 40 ABSOLUTE MAXIMUM RA T INGS Table 3. Paramet er Rating Analog Su pply V oltag e (A VDD) 2 V Digital Su pply Voltag e (DVDD ) 2 V Digital I/ O Supply Vo ltage (DVDD_I/O) 3.6 V DA C Supply Voltage ( A VDD3 Pin s ) 3.6 V Maximu m Digital I nput V oltage −0.5 V to D VDD_ I/O + 0. 5 V Storag e T e mpera ture −65°C t o +[...]

AD9912 Rev. D | P age 8 of 40 PIN CONFIGURA TION AND FUNCTION DE SCRIPTI ONS PIN 1 INDI C A T OR 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 NC NC A V DD NC NC NC A V DD A V DD A V DD A V DD SYSCLK SYSCLKB A V DD A V DD LOOP_ FI L T ER CLKM ODES E L 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 SCL K SDI O SDO CSB IO _UPD A TE RESET PW RDOW N[...]

AD9912 Rev. D | P age 9 of 40 P i n N o. Input / Output P i n Ty p e Mnemonic Descriptio n 32 I 1.8 V CMO S CLK MODE SEL Clock Mode Selec t. Set to GND whe n connecting a cr ystal to the system clock inp ut (P in 27 and P in 28). P ull up to 1.8 V whe n using ei ther an oscillator or an external cloc k sourc e . This pin c an be l eft uncon nected [...]

AD9912 Rev. D | P age 10 of 40 TYPICAL PERFORMA NCE CHARACTERIST ICS AV D D , AV D D 3 , a n d D VDD a t nominal supp ly vol tage; DAC R SET = 10 k Ω, unless otherwis e noted. See Fig ure 26 for 1 GHz re fe re nce pha s e n oi se used for gen era ting these p lo ts . 06763-003 0 100 200 300 400 500 OUT PUT F REQ UE NCY ( M Hz) –50 –55 –60 ?[...]

AD9912 Rev. D | P age 11 of 40 06763-009 19.85 19. 95 20. 05 20.15 20.25 20. 35 FREQUENCY (MH z) 10 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 SI G NAL P O W E R ( d Bm) 20.1M Hz –95dBc 500kHz 300Hz 1kHz CARRIE R: SF DR: FRE Q . S P AN: RE SOLUTION BW: VI DE O BW: Figure 9 . Narrow -B and SFDR at 20.1 MHz , SYSCLK = 1 G[...]

AD9912 Rev. D | P age 12 of 40 06763-015 100 1k 10k 100k 1M 10M 100M FREQUENCY OFFSET (Hz) –100 –110 –120 –130 –140 –150 PHASE N OISE (d Bc/Hz) 800MHz 600MHz RMS JI TT ER (100Hz T O 100M Hz) : 600MHz: 800MHz: 585fs 406fs Figure 15 . Absolute Phase Noise U sing H STL Driver , SYSCLK = 1 GHz Wenzel Oscilla tor ( SYSCLK PLL By pass ed) , H[...]

AD9912 Rev. D | P age 13 of 40 06763-051 100 1k 10k 100k 1M 10M 100M FREQUENCY OFFSET (Hz) –125 –115 –135 –145 –155 –165 –175 PHASE N OISE (d Bc/Hz) RMS JI TT ER (100Hz T O 20M Hz) : 50MHz: 200MHz: 400MHz: 62fs 37fs 31fs 200MHz 400MHz 50MHz Figure 21 . Absolute Phase Noise of U nfiltered DAC Output , f OUT = 50 MHz, 200 MH z, and 400 [...]

AD9912 Rev. D | P age 14 of 40 06763-021 0 200 400 600 800 FREQUENCY (MH z) 650 600 550 500 450 AMPLITUDE (mV) NOM S KE W 25°C, 1. 8V S UP P L Y WORST CASE (SLOW SKEW 90°C, 1.7V SUPPLY) Figure 27 . HSTL Out pu t Driver Single - En ded Peak -to- Pe ak Amplitud e vs. Toggle Rate (100 Ω Across Differential P air) 06763-022 0 10 20 30 40 FREQUENCY ([...]

AD9912 Rev. D | P age 15 of 40 INPUT/OUTPUT TER MINA TION RECOMM EN DA TIONS DOW NST REAM DEVI CE (H IGH-Z) AD9912 1.8V HST L OUT PUT 100 Ω 06763-027 0.01µ F 0.01µ F Figure 33 . AC - Coupled HST L Output Driver DOW NST REAM DEVI CE (H IGH-Z) AD9912 1.8V HST L OUT PUT 50 Ω 50 Ω 06763-028 AVDD/ 2 Figure 34 . DC - Coupled HST L Output Driver A[...]

AD9912 Rev. D | P age 16 of 40 THEOR Y OF OPERA TION 06763-031 DDS/ DAC FRE QUENCY TUNI NG W O RD ÷S 2× DIGI TAL SY NTHES IS CORE CONT ROL LOGIC LOW NOIS E CLO CK MU LTIPLIER AMP SYSCLK PORT EXT ERNAL ANALO G LOW -PASS FILTER EXT ERNAL LOOP FILTER DIGITA L INT ERF ACE SYSCLK SYSCLKB S1 TO S4 FDBK_I N FDBK_I NB DAC_OUT DAC_OUT B OUT OUTB OUT _CMO [...]

AD9912 Rev. D | P age 17 of 40 06763-032 DAC (14-BI T) AN GLE TO AMPL IT UDE CONVE RSI ON 14 19 19 48 48 48 14 PHASE OFFSET Q D 48-BIT ACCUMUL ATO R FREQ UENCY TUNI NG W O RD (FTW) f S DAC_RSET DAC_OUT DAC_OUT B DAC I-S E T REGISTERS AN D LOGIC Figure 40 . DDS Block Diagram The inp ut to the DDS is a 4 8- bit FT W that pro vides the accu - m ula to[...]

AD9912 Rev. D | P age 18 of 40 PRI MARY SI GNAL FILTER RESPONSE SIN(x)/x ENVELOPE SPURS IMAGE 0 IMAGE 1 IMAGE 2 IMAGE 3 IMAGE 4 0 –20 –40 –60 –80 –100 MAG NIT UDE (d B) f s /2 f s 3 f s /2 2 f s 5 f s /2 f BASE BAND 06763-034 Figure 42 . DAC Spectrum vs. Recons truction Filter R esponse Be ca use the D AC con stitu tes a samp led system, [...]

AD9912 Rev. D | P age 19 of 40 SYSC LK INPUTS Funct i onal D escription A n exter nal ti me base connects to the AD9912 at the SY SCLK pins t o genera te the in ternal hig h frequenc y system clock (f S ). The S Y SCLK in pu ts can be o perated i n on e of the following thr ee modes: • S Y SCLK P LL byp assed • S Y SCLK P LL ena bled w ith inpu[...]

AD9912 Rev. D | P age 20 of 40 SYSCLK PLL Multiplier When the SY SCLK PLL multiplier path is employ ed, the freq uency a pp lied to t he S Y SCLK inp ut pin s m ust be limi ted so as n ot t o ex ceed the maxi mu m in pu t freq uency of the S Y SCLK PLL p hase detecto r . A block di agram of th e SY SCLK gener at or app e ars i n Fig u re 45 . 06763[...]

AD9912 Rev. D | P age 21 of 40 N ote t ha t the SY SCLK PLL b ypassed a nd S Y SCLK P LL ena bl ed input pat hs a re in te rna lly biase d to a d c level of ~1 V . Care should be taken to ensure that an y external connections do not disturb the dc bias be cause this may sign ifica ntl y degra de perform ance. Gener ally , it i s recommend ed that t[...]

AD9912 Rev. D | P age 22 of 40 Although the worst spurs tend to be harmonic in origin , the fact that the D AC is part of a sampled system results in the poss ibility of sp urs ap pearing in the outp ut spec tru m that are not harmoni - cally r elated to t he fundamen tal. F or exam ple, if the DA C is sampled at 1 GH z and ge ner ates an output si[...]

AD9912 Rev. D | P age 23 of 40 THERMAL PERFOR MANCE Table 7 . Thermal Paramete rs Symbo l Therm al Char acterist ic Us ing a JE DEC51 - 7 Plus JE DEC51 - 5 2S 2P T est B oard Valu e Unit θ JA Ju nc t i on - to - ambient t hermal r esistance , 0.0 m/s ec a ir flow per JE DEC JESD51 - 2 (still ai r) 25.2 °C/W θ JMA Jun c ti on - to - ambient ther [...]

AD9912 Rev. D | P age 24 of 40 POWER-UP POWER - ON RESET On initial power - up, t h e AD991 2 in terna lly genera tes a 75 ns RESET pulse. The puls e is initiated when b oth o f the following two condition s are met: • The 3.3 V supp ly is gr eater than 2.35 V ± 0.1 V . • The 1.8 V supp ly is gr eater than 1.4 V ± 0.05 V . Less than 1 ns afte[...]

AD9912 Rev. D | P age 25 of 40 POWER SUPPL Y PAR TITI ONING The AD9912 feat ures m ultiple pow er supp lies, and their power consum ption varies with its configuration. This s ection covers which power supp lies can be grouped together and how the powe r cons u mpti on of each blo ck v ar ies with f requency . The numbers quoted he re are for com p[...]

AD9912 Rev. D | P age 26 of 40 SERIAL CONTROL PORT The AD9912 se rial contr ol port is a flexible, synchro nous, serial co m m unications port that allows an easy interface with many indus tr y - standard microcon trollers and micr op rocessors. Single or m ultip le byte transf ers are su pported, as well as MSB first o r LSB first t ransfer forma [...]

AD9912 Rev. D | P age 27 of 40 Read If the instr ucti on wor d is for a rea d operation (I15 = 1), the next N × 8 SCLK cy cles c lock ou t the da ta from t he address specified in the instruction word, where N is 1, 2, 3, or 4, as deter mined by [ W1:W0 ] . In this case, 4 is used for str eaming m ode where fou r or mor e words a r e transf erred [...]

AD9912 Rev. D | P age 28 of 40 Table 10 . Serial Control Port, 16 - Bit Instr uction Word , MSB F irst MSB LS B I15 I14 I13 I 12 I11 I10 I9 I8 I7 I6 I5 I4 I3 I2 I1 I0 R/ W W1 W0 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 06763-043 CSB SCLK DON' T CARE SDIO A12 W0 W1 R/W A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D[...]

AD9912 Rev. D | P age 29 of 40 06763-048 CSB SCL K SDI O t H IGH t LOW t CLK t S t DS t DH t H BIT N BIT N + 1 Figure 56 . Serial Co ntrol Port Timing — Write Table 11 . De finit ions o f Ter ms Used in Seria l Cont rol Port Tim ing Diagr ams Paramet er Descrip tion t CLK P eriod of SCLK t DV Rea d dat a valid time (t ime fro m f allin g edge of [...]

AD9912 Rev. D | P age 30 of 40 I/O REGISTER MAP All address and bi t location s that ar e left blank in Ta b l e 12 ar e unu sed . Table 12 . Addr (Hex) Type 1 Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Default (Hex) Serial port con figuration and pa rt i dentification 0x0000 Serial c onfi g. SDO a ctive LSB f ir st (buff ered) Soft r ese[...]

AD9912 Rev. D | P age 31 of 40 Addr (Hex) Type 1 Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Default (Hex) Calibration (user - acc essibl e t rim) 0x0400 to 0x040A Reserv ed 0x00 0x040B DAC full- scale c urrent DAC full -s cale c urrent , Bits[7:0] 0x FF 0x040C DAC full - scale c urrent , Bits[9: 8] 0x01 0x040D Reserv ed 0x00 0x040E Reserv[...]

AD9912 Rev. D | P age 32 of 40 I/O REGISTER DESC RIP TION S SERI AL PORT C ONFIGUR ATION (R EG IS TER 0x 0000 TO REG IST ER 0x 0005) Regist er 0x0000 —Serial P ort Config urat ion Table 13 . Bits B it Name Descript ion [7:4] These b its ar e the mirror imag e of Bit s[3:0 ]. 3 Lo ng i ns truc ti on Rea d - only ; th e AD9912 suppor ts only long i[...]

AD9912 Rev. D | P age 33 of 40 Regist er 0x0011 — Reserved Regist er 0x0012 — Res et ( Autoc learing) To reset t he en tir e chi p , the user c an use the (non - auto cl eari ng) soft r es et bit in Register 0x0000. Table 17 . Bits B it Name Descript ion 0 DDS r eset R eset of the d irect d igital s ynt hes is block. R eset of t his bl ock is v[...]

AD9912 Rev. D | P age 34 of 40 CMOS O UTPUT DIVIDE R (S -DIVIDER) (REG ISTER 0x 0100 TO REG ISTER 0x 0106) Regist er 0x 0100 to Registe r 0x0103 — Reserv ed Regist er 0x0104 —S- Di vider Table 21 . Bits B it Name Descript ion [7:0] S-d ivider CMOS out put divider . Div ide ra tio = 1 − 65,536. If t he des ired S - d ivider s etting is grea te[...]

AD9912 Rev. D | P age 35 of 40 Regist er 0x01A9 — FTW0 ( Fr equen cy T unin g W ord) (Con ti nued) Table 27 . Bit s Bit Name Desc riptio n [31:24] FT W0 These r egist ers conta in the FT W (fr equency tu ning w ord) f or the D DS. The FT W det ermin es the ratio of the A D9912 outpu t frequ ency to it s DA C sys tem c lock. Reg iste r 0x 01 A6 is[...]

AD9912 Rev. D | P age 36 of 40 DOUBLER AND O UTPUT D RIVER S (RE G ISTE R 0x 0200 TO REG IS TE R 0x 0201) Regist er 0x0200 — HSTL Driver Table 32 . Bits B it Name Descript ion 4 OPOL Out put pola rity . Sett ing th is bit inv er ts the HS TL driv er output po larity . [3:2] Reserved Reserved . [ 1: 0] HSTL outp ut d oubler HSTL output doub ler. 0[...]

AD9912 Rev. D | P age 37 of 40 Regist er 0x0503 — Sp ur A (C ontin ued) Table 38 . Bit s Bit Na me Descr iptio n [7:0] Spur A phase Linear o ffs et fo r Spu r B phas e. Regist er 0x0504 — Sp ur A (C ontin ued) Table 39 . Bits B it Name Descript ion [8] Sp ur A p h as e Linear of fs et for S pur A phase . Regist er 0x0505 — Sp ur B Table 40 . [...]

AD9912 Rev. D | P age 38 of 40 OUTLINE DIMENSIO NS PIN 1 INDI C A T OR T OP VIEW 8. 75 BSC SQ 9.00 BSC SQ 1 64 16 17 49 48 32 33 0.50 0.40 0.30 0.50 BS C 0. 20 RE F 12° M AX 0.80 M AX 0.65 T Y P 1.00 0.85 0.80 7.50 REF 0.05 M AX 0.02 NO M 0.60 M AX 0.60 M AX * 4.85 4.70 S Q 4.55 EXPOSED PAD (BOT TOM VIE W) * COM P L IANT T O JEDEC S T ANDARDS M O [...]

AD9912 Rev. D | P age 39 of 40 ORDERING GUIDE Model T emper atu re Rang e Package De scription P ackage Op tion AD9912A B C PZ 1 , 2 −40°C to +85° C 64 - Lea d Lea d F rame Ch ip Scal e P ackage [ LFCSP_VQ ] CP - 64 -7 AD9912A B C PZ - REEL7 1 , 2 −40°C t o +85°C 64 - Lead L ead F rame Chip Sca le P ackage [LFCSP _VQ] CP - 64 -7 AD9912B CPZ[...]

AD9912 Rev. D | P age 40 of 40 NOTES © 2007 – 2009 Anal og De vice s, Inc. All rights reserved. Tradema rks and registe red trad emarks are the pro perty of their resp ective o wners. D06763 -0- 11/09(D)[...]