background image

1

dc1705cfa

DEMO MANUAL DC1705C

Description

LTC6946

Ultralow Noise and Spurious Integer-N 

Frequency Synthesizer with Integrated VCO

DC1705C features the LTC

®

6946, an ultralow noise and 

spurious integer-N frequency synthesizer with integrated 

VCO. The VCO uses no external components and is inter-

nally calibrated without external system support.
There are three versions of the DC1705C, one for each 

version of the LTC6946. The DC1705C-A contains the 

LTC6946-1, the DC1705C-B incorporates the LTC6946-2 

and DC1705C-C uses the LTC6946-3.

Each DC1705C provides 50Ω SMA connectors for the 

reference frequency input, f

REF

 (REF+ IN), the reference 

output buffer (REF OUT), and the differential RF output 

(RF

+

 and RF

). A DC590 USB serial controller board is 

used for SPI communication with the LTC6946, controlled 

by the supplied PLLWizard™ software. 

Design files for this circuit board are available at  

http://www.linear.com/demo

L

, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and 

PLLWizard and QuikEval are trademarks of Linear Technology Corporation. All other trademarks 

are the property of their respective owners.

Figure 1. Proper Measurement Equipment Setup

Summary of Contents for DC1705B

Page 1: ...rates the LTC6946 2 and DC1705C C uses the LTC6946 3 Each DC1705C provides 50Ω SMA connectors for the reference frequency input fREF REF IN the reference output buffer REF OUT and the differential RF output RF and RF A DC590 USB serial controller board is usedforSPIcommunicationwiththeLTC6946 controlled by the supplied PLLWizard software Design files for this circuit board are available at http ww...

Page 2: ...BLY VERSION PART NUMBER VCO FREQUENCY RANGE GHz OUTPUT DIVIDER SETTINGS DC1705C A LTC6946IUFD 1 2 240 to 3 740 Integers 1 through 6 DC1705C B LTC6946IUFD 2 3 080 to 4 910 Integers 1 through 6 DC1705C C LTC6946IUFD 3 3 840 to 5 790 Integers 1 through 6 Typical DC1705C Requirements and Characteristics Quick Start Procedure The DC590 and PLLWizard application are required to control the DC1705C throu...

Page 3: ...tem Windows XP Windows 2003 Server Windows Vista Windows 7 Microsoft NET 2 0 or later Windows Installer 3 1 or later Linear Technology s QuikEval and DC590 hardware Microsoft NET You must have Microsoft NET 2 0 or later installed on yourcomputer PLLWizardwillnotrunwithoutit Notethat with Windows Vista and Windows 7 you should have at least version 3 5 pre installed To manually determine your versi...

Page 4: ...ation File FILE NET 2 0 SOURCE PLLWizardSetup exe Latest Version Downloaded from Microsoft PLLWizardSetup_net20 exe 2 0 SP2 Included Much Larger File Size Choose PLLWizardSetup if you have NET 2 0 or later have Windows Vista or Windows 7 or if you have less than NET 2 0 but want the latest NET installed Choose PLLWizardSetup_net20 if you have less than NET 2 0 and want faster installation no addit...

Page 5: ... found in the PLLWizard installation directory typically Program Files LTC PLLWizard Set Files The red LED on DC1705C should turn on indicating that the loop is locked at 900MHz You can then change the values of N_DIV and or O_DIV in PLLWizard to change the output frequency Troubleshooting If the red LED does not illuminate follow the instructions below 1 Verify that you are able to communicate wi...

Page 6: ...6 dc1705cfa DEMO MANUAL DC1705C Figure 4 DC1705C Components and Connections quick start procedure ...

Page 7: ... Header 14 Pin 2mm MOLEX 87831 1420 17 4 J6 J7 J8 J9 JACK BANANA KEYSTONE 575 4 18 2 L1 L2 IND 68nH 5 0402 COILCRAFT 0402HPH 68NXJLW 19 1 RZ RES CHIP 453Ω 1 10W 1 0603 NIC NRC06F4530TRF 20 1 R1 RES CHIP 51 1Ω 1 16W 1 0402 NIC NRC04F51R1TRF 21 1 R3 RES CHIP 330Ω 1 16W 1 0402 NIC NRC04F3300TRF 22 1 R4 RES CHIP 15Ω 1 16W 1 0402 NIC NRC04F15R0TRF 23 4 R5 R6 R7 R13 RES CHIP 200K 1 16W 1 0402 NIC NRC04F...

Page 8: ...Y AND SCHEMATIC SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS SCALE NONE www linear com 1 DEMO CIRCUIT 1705C 01 22 2013 12 44 PM 1 2 ULTRALOW NOISE SPURIOUS INTEGER N N A LTC6946IUFD 1 2 3 KIM T MICHEL A SYNTHESIZER WITH INTEGRATED VCO SIZE DATE IC NO REV SHEET OF TITLE APPROVALS PCB DES APP ENG TECHNOLOGY Fax 408 434 0507 Milpitas CA 95035 Phone 408 432 1900 1630 McCarthy Blvd LTC Confidential Fo...

Page 9: ...LY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SCHEMATIC SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS SCALE NONE www linear com 1 DEMO CIRCUIT 1705C 01 22 2013 12 44 PM 2 2 ULTRALOW NOISE SPURIOUS INTEGER N N A LTC6946IUFD 1 2 3 KIM T MICHEL A SYNTHESIZER WITH INTEGRATED VCO SIZE D...

Page 10: ...10 dc1705cfa DEMO MANUAL DC1705C Layout The top metal layer of the DC1705C is shown here as an example of good PCB layout for the LTC6946 ...

Page 11: ...is assumed for its use Linear Technology Corporation makes no representa tion that the interconnection of its circuits as described herein will not infringe on existing patent rights Revision History BOARD REV DATE DESCRIPTION Original Design B 03 12 Added EEPROM for identification purposes C 05 13 Added support for 5V SPI in addition to the default 3 3V ...

Page 12: ...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...

Reviews: