DEMO MANUAL DC2091A LTC5599 30MHz to 1300MHz Low Power Direct Quadrature Modulator Description Demonstration circuit 2091A is optimized for evaluation of the LTC®5599 low power direct quadrature modulator. The balanced I and Q baseband input ports can be either AC- or DC-coupled to a source with a common mode voltage level of about 1.4V. Fixed LC networks on the LO and RF ports cover a continuous 90MHz to 1300MHz range. The SPI interface controls the supply current, modulator gain, and allows optimization of the LO carrier feedthrough and side-band suppression. Design files for this circuit board are available at http://www.linear.com/demo/DC2091A L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and QuikEval is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Measurement Setup BB SIGNAL SOURCE (VCMBB = 1.4VDC) I+ I– Q+ Q– –6dB –3dB LO SIGNAL SOURCE SPECTRUM ANALYZER – + DC POWER SUPPLY (3.3V) DC2091 F01 Figure 1. Test Setup for RF Performance Measurements dc2091afa 1 DEMO MANUAL DC2091A Absolute Maximum Input Ratings Supply Voltage..........................................................3.8V Common Mode Level of BBPI, BBMI, and BBPQ, BBMQ....................................................2V LOL, LOC DC Voltage.............................................. ±0.1V LOL, LOC Input Power..........................................20dBm Voltage on Any Pin............................–0.3V to VCC + 0.3V TJMAX..................................................................... 150°C Case Operating Temperature Range........ –40°C to 105°C Storage Temperature Range................... –65°C to 150°C CAUTION: This part is sensitive to electrostatic discharge (ESD). Observe proper ESD precautions when handling the LTC5599. Notes on Test Equipment and Setup • Use high performance signal generators with fully configurable differential I and Q outputs, such as the Rohde & Schwarz SMJ100A vector signal generator or equivalent. • Use narrow resolution bandwidth (RBW) and engage video averaging on the spectrum analyzer to lower the displayed average noise level (DANL) in order to improve sensitivity and to increase dynamic range. The trade-off is increased sweep time. • Spectrum analyzers can produce significant internal distortion products if they are overdriven. Generally, spectrum analyzers are designed to operate at their best with about –30dBm to –40dBm at their input filter or preselector. Sufficient spectrum analyzer input attenuation should be used to avoid saturating the instrument, but too much attenuation reduces sensitivity and dynamic range. • Before taking measurements, the system performance should be evaluated to ensure that: 1) clean input signals can be produced 2) the spectrum analyzer’s internal distortion is minimized 3) the spectrum analyzer has enough dynamic range and sensitivity 4) the system is accurately calibrated for power and frequency. • Digital modulation often requires DC coupling and flat frequency response. For best EVM performance with complex modulation, the RC networks at the baseband I/Q inputs are not required. Quick Start Procedure 1. Remove the demonstration circuit from its protective packaging in an ESD-safe working area. 2. Turn off the DC power supply as well as the baseband and LO signal sources’ outputs. 3. Connect all test equipment as show in Figure 1. 4. Make sure jumper JP1 is installed and the jumper JP2 is installed at the 1-2 position. 5. Slowly increase the supply voltage to 3.3V. Do not exceed 3.8V. 6. Turn on the baseband signal source. Set the baseband common mode bias to 1.4V. 2 7. Verify the total VCC supply current is approximately 28mA. The demonstration circuit is now turned on and is ready for measurements. 8. Turn on the output of the LO source and apply a 492.8MHz, 0dBm CW Signal. 9. Set the baseband signal source to provide a 100kHz, 200mVP-P(DIFF) baseband input signal. The I and Q channels should be 90° shifted and set for lower sideband selection. 10.Measure the modulator’s RF output on the Spectrum Analyzer at 492.7MHz. dc2091afa DEMO MANUAL DC2091A Quick Start Procedure 11.Calculate the Voltage Conversion Gain: Gain = 20 • log (VRF(OUT)(50Ω) / VIN(DIFF)(I OR Q)) 12.Measure the Output 1dB Compression Point by increasing the input signal level until the Voltage Conversion Gain degrades by 1dB. 13.Measure the Image Rejection at 492.9MHz. 15.Connect the DC590B to the DC2091A with the ribbon cable provided. Make sure jumper JP6 on the DC590B is set to 3.3V. 16.Run QuikEval® to start the GUI associated with the LTC5599. 17.The turn off procedure is the reverse of the turn on procedure. Make sure VCC is removed after VEN. 14.Measure the LO Leakage at 492.8MHz. Demo Board Schematic VCC 3.3V GND EN E1 FB1 330Ω AT 100MHz C1 4.7µF E2 SDO SDI E3 2 VCTRL VCC E4 JP1 1 R1, 1Ω 2 J1 L1, 39nH C5, 15pF CS 25 24 23 22 21 20 19 GND VCC EN SDO SDI SCLK CSB C3 0.1µF 1 LO SCLK C2, 1000pF VCTRL GNDRF GND GNDRF 3 LOL LTC5599IUF 4 LOC 5 GND TTCK TEMP BBMI BBPI E5 GNDRF GNDRF GNDRF 6 TTCK C4 0.01µF 17 J2 16 15 14 13 J4 R4, 0Ω R6, 0Ω J6 J3 R3, 0Ω R5, 0Ω J5 R2, OPT E7 RF TEMP BBPI BBMI BBPQ BBMQ GND 8 7 9 10 12 11 E6 R8 49.9Ω GND RF 18 C6 0.1µF BBMQ BBPQ R12, OPT R9 49.9Ω C7 0.1µF * R10 49.9Ω C8 0.1µF R11 49.9Ω * C9 0.1µF DC2091 F02 * REMOVE THE RC NETWORK FOR BEST EVM WITH COMPLEX DIGITAL MODULATION. Figure 2. Low Power I/Q Modulator Schematic dc2091afa 3 DEMO MANUAL DC2091A Demo Board schematic VCC U5 NC7WZ17P6X VCC_L R22 200k 1 2 3 1 R23 1k 6 C10 2.2pF 3 JP1 4 CS R25 1k SCLK VCC_L 2 E8 VCC_L GND VCC C12 2.2pF 5 C11 0.1µF U3 NC7WZ17P6X R26 1k 6 1 C13 2.2pF 3 4 2 5 SDI VCC_L GND VCC C14 0.1µF P1 HD-2X7.0.79 ISO_7V_UNREG ISO_5V_3p3v_REG ISO_CSb ISO_SCK_SCL ISO_SDA_MOSI ISO_MISO EE_VCC EE_SDA EE_SCL EE_GND ISO_GND ISO_GND 3 8 13 ISO_GND GPI01 U4 74LVC1T45GW 1 2 1 6 C15 0.1µF 2 4 7 R20 100Ω 5 VCC_A GND VCC_B DIR 6 C17 0.1µF C16 0.1µF 5 R18 4.99k R19 1k 4 3 VCC_L VCC_L C18 2.2pF 10 9 SDO 11 12 U2 24LC025 14 R15 4.99k R14 4.99k R13 4.99k 8 V CC 7 WP A0 6 SCL 5 SDA A2 A1 VSS 1 2 3 4 DC2091 F03 Figure 3. Demo Board SPI Interface 4 dc2091afa DEMO MANUAL DC2091A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components 1 1 C1 CAP., X5R, 4.7µF, 10%, 16V, 0603 MURATA, GRM188R61C475KAAJD 2 1 C2 CAP., C0G, 1000pF, 5%, 50V, 0402 MURATA, GRM1555C1H102JA01D 3 10 C3, C6–C9, C11, C14–C17 CAP., X7R, 0.1µF, 10%, 16V, 0402 MURATA, GRM155R71C104KA88D 4 1 C4 CAP., X7R, 0.01µF, 10%, 16V, 0402 MURATA, GRM155R71C103KA01D 5 1 C5 CAP., COG, 15pF, 5%, 50V, 0402 MURATA, GRM1555C1H150JA01D 6 4 C10, C12, C13, C18 CAP.,COG, 2.2pF,+/-.1pF, 25V, 0402 MURATA, GRM1555C1E2R2BZ01D 7 5 E1, E2, E3, E7, E8 TESTPOINT, TURRET, .094" MILL-MAX, 2501-2-00-80-00-00-07-0 8 3 E4, E5, E6 TESTPOINT, TURRET, .063" MILL-MAX, 2308-2-00-80-00-00-07-0 9 1 FB1 FERRITE BEAD, 33Ω @100MHz TDK, MPZ1608S331AT 10 1 JP1 HEADER, 2 PIN, 0.079 SINGLE ROW SULLINS, NRPN021PAEN-RC 11 1 JP2 HEADER, 3 PIN, 0.079 SINGLE ROW SULLINS, NRPN031PAEN-RC 12 2 XJP4, XJP5 SHUNT, 2mm Ctrs. SAMTEC, 2SN-BK-G 13 6 J1–J6 CONN., SMA, 50Ω, EDGE-LANCH E.F.JOHNSON, 142-0701-851 14 1 L1 IND., 39nH, 0402HP COILCRAFT, 0402HP-39NXJLU 15 1 P1 HEADER, 2X7PIN, 0.079CC MOLEX, 87831-1420 16 1 R1 RES., CHIP, 1Ω, 1%, 0402 VISHAY, CRCW04021R00FNED 17 0 R2, R12 OPT, 0402 18 4 R3, R4, R5, R6 RES., CHIP, 0Ω, 0402 VISHAY, CRCW04020000Z0ED 19 4 R8, R9, R10, R11 RES., CHIP, 49.9Ω, 1%, 0402 VISHAY, CRCW040249R9FKED 20 3 R13, R14, R15 RES., CHIP, 4.99K, 1%, 0402 VISHAY, CRCW04024K99FKED 21 5 R18, R19, R23, R25, R26 RES., CHIP, 1K, 1%, 0402 VISHAY, CRCW04021K00FKED 22 1 R20 RES., CHIP, 100Ω, 1%, 0402 VISHAY, CRCW0402100RFKED 23 1 R22 RES., CHIP, 200K, 1%, 0402 VISHAY, CRCW0402200KFKEA 24 1 U1 IC., LTC5599, QFN-24-4X4 LINEAR TECHNOLOGY, LTC5599IUF#PBF 25 1 U2 IC, EEPROM 2KBIT 400KHZ 8TSSOP MICROCHIP TECH., 24LC025-I/ST 26 2 U3, U5 I.C., DUAL BUFFER SCHMT TRIG UHS SC706 FAIRCHILD SEMI., NC7WZ17P6X 27 1 U4 I.C., DUAL TRANSCEIVER 3ST 6TSSOP NXP, 74LVC1T45GW,125 28 1 FAB, PRINTED CIRCUIT BOARD DEMO CIRCUIT DC2091A dc2091afa Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 5 DEMO MANUAL DC2091A DEMONSTRATION BOARD IMPORTANT NOTICE Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions: This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations. If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES. The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or agency certified (FCC, UL, CE, etc.). No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance, customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind. LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive. Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and observe good laboratory practice standards. Common sense is encouraged. This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer. Mailing Address: Linear Technology 1630 McCarthy Blvd. Milpitas, CA 95035 Copyright © 2004, Linear Technology Corporation 6 dc2091afa Linear Technology Corporation LT 1115 REV A • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2014