RF-Class TxDAC® High Performance MixMode™ DACs 1st Generation 2nd Generation Single AD9739 14b, 2.5 GSPS Single Single AD9736/35/34 AD9789 14-10b, 1.2 GSPS 2x Interpolation 14b, 2.4 GSPS Highly Integrated All LVDS Inputs 1 —Analog Devices Confidential Information— RFDAC Frequency Coverage 1st 2nd 3rd 0 1 21 41 61 81 Mix RZ T(f) (dB) -10 Normal -20 -30 -40 0.5FS 2 FS 1.5FS —Analog Devices Confidential Information— 2FS RFDAC Normal Mode Output Spectrum 0 1 21 41 61 81 Mix RZ T(f) (dB) -10 Normal -20 -30 -40 0.5FS 3 FS 1.5FS —Analog Devices Confidential Information— 2FS RFDAC in MixModeTM Output Spectrum 0 1 21 41 61 81 Mix RZ T(f) (dB) -10 Normal -20 -30 -40 0.5FS 4 FS 1.5FS —Analog Devices Confidential Information— 2FS DAC Quad Switch Enables RF Upconversion Theory vs. Practice Frequency Response (using OFDM test vector) @ DACCLK=2.4 GHz Mix-Mode (blue trace) nd Nyquist zone (i.e. 1.2 to 2.4 GHz) Flat RF Passband in 2 rd Small Region in 3 Nyquist zone available Bandwidth roll-off beyond 2.5 Ghz also attributed to transformer, impedance matching, RF DAC core output bandwidth FIRST NYQUIST ZONE SECOND NYQUIST ZONE 0 THIRD NYQUIST ZONE MIX MODE –5 RZ MODE –10 –15 NORMAL MODE –20 –25 –35 0FS 0.25FS 0.50FS 0.75FS 1.00FS FREQUENCY (Hz) 5 1.25FS 1.50FS 07851-080 –30 Figure 1a. Plot compares different modes of operation using Mix-Mode EVB using MABACT0039 Balun. Normal Mode(Pink), RTZ Mode(Yellow), and Mix-Mode (White). —Analog Devices Confidential Information— 1-Carrier WCDMA ACLR Results (FDAC = 2,457.6MSPS) -40 -50 -45 -55 2nd Nyquist Zone 3rd Nyquist Zone -50 Normal Mode -65 -70 1st ADJ CH -75 MixModeTM -55 ACLR - dBc ACLR - dBc -60 -60 -65 1st ADJ CH -70 -75 -80 2nd ADJ CH -80 -85 5th ADJ CH -85 2nd ADJ CH -90 0 6 122.88 245.76 368.64 491.52 614.4 737.28 Fout - MHz 860.16 983.04 1105.9 1228.8 5th ADJ CH -90 1229 1475 1720 1966 2212 2458 2703 2949 3195 3441 3686 —Analog Devices Confidential Information— Fout - MHz AD9739: RF Performance 4-carrier ACLR at 2.1 GHz 10dB/DIV 10dB/DIV 4-carrier ACLR at 2.8 GHz REF BW (MHz) 3.84 3.84 3.84 3.84 3.84 3.84 LOWER (dBc) (dBm) 0.22 –25.31 –66.68 –92.21 –68.01 –93.53 –68.61 –94.14 –68.87 –94.40 –69.21 –94.74 UPPER (dBc) (dBm) 0.24 –25.29 0.14 –25.38 –66.82 –92.35 –67.83 –93.36 –67.64 –93.17 –68.50 –94.03 CENTER 2.81271GHz #RES BW 30kHz FREQ REF RMS RESULTS OFFSET BW CARRIER POWER (MHz) 5 –27.98dBm/ 10 3.84MHz 15 20 25 30 ACLR=67+ dBc 7 VBW 300kHz SPAN 63.84MHz SWEEP 207ms (601pts) (MHz) 3.84 3.84 3.84 3.84 3.84 3.84 LOWER (dBc) (dBm) –0.42 –28.40 –64.32 –92.30 –66.03 –94.01 –66.27 –94.24 –66.82 –94.79 –67.16 –95.13 ACLR=64+ dBc —Analog Devices Confidential Information— UPPER (dBc) (dBm) –0.10 –28.07 –0.08 –28.06 –65.37 –93.34 –66.06 –94.03 –63.36 –93.34 –66.54 –94.51 07851-042 VBW 300kHz FREQ RMS RESULTS OFFSET CARRIER POWER (MHz) 5 –25.53dBm/ 10 3.84MHz 15 20 25 30 SPAN 63.84MHz SWEEP 207ms (601pts) 07851-043 CENTER 2.09758GHz #RES BW 30kHz The World Leader in High Performance Signal Processing Solutions Signal Chain comparison DAC + IF Filter + Modulator Architecture Complex-IF/ZIF Tx Architecture High Speed Dual DAC AD9122/ AD9125/ AD9146/AD9148 ASIC/FPGA • Low speed fabric • Low speed interface Customer IP 9 QDUC ADL5375 IF DAC Fine NCO Inv SINC ADRF670x Modulator IF DAC —Analog Devices Confidential Information— VGA PA Direct-RF DAC Architecture Direct Real-RF Tx Architecture ASIC/FPGA • Low speed fabric • Low speed interface QDUC Coarse NCO? Customer IP Embedded RF DAC Inv SINC Fine NCO 10 —Analog Devices Confidential Information— VGA PA
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