DEMO MANUAL DC2349A LTC5586 6GHz High Linearity I/Q Demodulator with Wideband IF Amplifier DESCRIPTION Demonstration circuit 2349A showcases the LTC(R)5586 wideband high linearity IQ demodulator with IF amplifier. The Linear Technology USB serial controller, DC590B, is required to control and configure LTC5586 for its evaluation. Demo circuit 2349A's two switchable single-ended RF inputs are optimized for 700MHz to 6GHz. Its singleended LO input is programmable for 300MHz to 6GHz operation via SPI bus. The demo circuit includes discrete L-C inter-stage lowpass filters between the demodulator outputs and the IF amplifier inputs, which limits the DC-coupled differential I and Q outputs to about 500MHz (-1dB bandwidth). By writing to specific registers through SPI bus, LTC5586's RF input step attenuator, IF amplifier gain, LO input frequency, output DC offset, image rejection, and linearity can be adjusted or optimized. Design files for this circuit board are available at http://www.linear.com/demo/DC2349A 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. BOARD PHOTO dc2349af 1 DEMO MANUAL DC2349A QUICK START PROCEDURE NOTE 1. Evaluation of demonstration circuit 2349A requires the Linear Technology USB serial controller, DC590B, and the Linear Technology QuikEvalTM software. Please refer to DC590B demo manual for their setup and installation. 5. When the DC2349A demo board is connected to the DC590B USB serial controller, the QuikEval software will automatically download and install the proper software GUI. NOTE 2. An internet connection is required for the automatic download and installation of the LTC5586 software GUI. If an internet connection is not available, contact Linear Technology for installation files 6. While monitoring the voltage on VSENSE, increase the VSUPPLY DC power supply voltage until VSENSE reaches 5V (VSUPPLY voltage should be approximately 5.5V). Verify the current consumption is close to the figure listed in the data sheet. NOTE 3. Refer to Figure 1 for proper equipment setup. NOTE 4. Make all connections without RF and DC applied. NOTE 5. Care should be taken to never exceed absolute maximum input ratings. 1. If not already done, install the QuikEval software and connect the DC590B USB serial controller to an internet-connected computer's USB port. 2. Set the DC590B's isolated supply voltage to 3.3V by moving its VCCIO jumper (JP6) to 3.3V position. 3. Verify that the DC2349A's jumpers are set to: 8. In the LTC5586 QuikEval computer GUI, verify that "Connected" is displayed, then press the "Soft Reset" button. See Figure 2. 9. Set the desired LO frequency and LO power, and turn on the LO signal source. 10. Use the LTC5586 QuikEval GUI to configure the LTC5586 to the same LO frequency. JP1 = INT (on-board 3.3V digital supply) 11. Set the desired RF frequency and RF power, and turn on the RF source. JP2 = RFA (RFA input selected) 12. Perform measurements. 4. While the RF sources and the DC power supplies are switched off, connect all test equipment as shown in Figure 1. 2 7. Increase the IF amplifier common-mode output voltage, VCM, to 0.9V. 13. The LTC5586 QuikEval GUI can be used to control and configure various functions of the LTC5586. Press the button "Show Regs" will make the LTC5586's internal register visible and accessible on screen. See Figure 3. dc2349af DEMO MANUAL DC2349A Figure 2. Proper Measurement Equipment Setup QUICK START PROCEDURE dc2349af 3 DEMO MANUAL DC2349A QUICK START PROCEDURE Figure 2. LTC5586 QuikEval GUI 4 dc2349af DEMO MANUAL DC2349A QUICK START PROCEDURE Figure 3. LTC5586 QuikEval GUI Showing Internal Resisters dc2349af 5 DEMO MANUAL DC2349A PCB LAYOUT 6 dc2349af DEMO MANUAL DC2349A PCB LAYOUT dc2349af 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. 7 DEMO MANUAL DC2349A 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 (c) 2004, Linear Technology Corporation 8 dc2349af Linear Technology Corporation LT 0616 * PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear.com (c) LINEAR TECHNOLOGY CORPORATION 2016