19-1111; Rev 0; 8/96 MAX3681 Evaluation Kit ______________Ordering Information PART MAX3681EVKIT-SO TEMP. RANGE -40°C to +85°C BOARD TYPE Surface Mount ____________________Component List DESIGNATION QTY DESCRIPTION C1–C4, C7 5 0.1µF ceramic capacitors C5 1 33µF, 6.3V tantalum capacitor Sprague 293D336X06R3C2 C6 1 2.2µF ceramic capacitor C8–C11 4 100pF ceramic capacitors J1–J16 16 SMA connectors (PC edge mount) L1 1 56nH inductor Coilcraft 0805CS-560 R1, R3, R5, R7 4 130Ω, 5% resistors R2, R4, R6, R8 4 82Ω, 5% resistors R9–R13 5 100Ω, 5% resistors U1 1 MAX3681EAG +3.3V, GND 2 2-pin headers None 1 MAX3681 data sheet SUPPLIER PHONE (847) 639-6400 (603) 224-1961 ♦ Single +3.3V Supply ♦ Inputs and Outputs Terminated for Interfacing with 3.3V PECL and LVDS Logic ♦ Fully Assembled and Tested _______________Detailed Description The MAX3681 EV kit simplifies evaluation of the MAX3681. The EV kit operates from a single +3.3V supply and includes all the external components necessary to interface with 3.3V PECL and LVDS logic. Each PECL input (SCLK+, SCLK-, SD+, SD-) is terminated on the EV board with the Thevenin equivalent of 50Ω to (VCC - 2V). These inputs can be driven directly by the output of any 3.3V PECL device, such as a clock-and-data-recovery circuit (e.g., the MAX3675). All LVDS outputs (PCLK+, PCLK-, PD_+, PD_-) are differentially terminated with 100Ω resistors between complementary outputs. Each output can directly drive an LVDS input or a high-impedance input oscilloscope (see the section Connecting LVDS Outputs to 50 Ω Input Oscilloscopes). When driving an LVDS input that already includes 100Ω differential termination, remove the termination resistor corresponding to the appropriate LVDS output. The synchronization inputs (SYNC+, SYNC-) are internally terminated LVDS inputs with 100Ω differential input resistance. Ensure that LVDS devices driving these inputs are not redundantly terminated. All signal inputs and outputs use coupled 50Ω transmission lines. All input signal lines are of equal length to minimize propagation-delay skew. Likewise, all output signal lines are of equal length. __________Applications Information Connecting LVDS Outputs to 50Ω Input Oscilloscopes ______________Component Suppliers Coilcraft Sprague ____________________________Features FAX (847) 639-1469 (603) 224-1430 To monitor an LVDS signal on a 50Ω input oscilloscope, remove the differential load resistor between the complementary outputs and AC couple each output to an oscilloscope input. For example, to observe the PD0 signal on a 50Ω input instrument, remove resistor R12 from the EV board and place a capacitor or DC block in series with each output (PD0+ or PD0-) and the instrument input. Do not connect MAX3681 outputs directly to 50Ω inputs or terminations to ground. Choose a coupling capacitor large enough in value to prevent pattern-dependent distortion of the output signal. ________________________________________________________________ Maxim Integrated Products 1 For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800 Evaluates: MAX3681 _______________General Description The MAX3681 evaluation kit (EV kit) simplifies evaluation of the MAX3681 622Mbps, SDH/SONET 1:4 deserializer. The EV kit requires only a single +3.3V supply and includes all the external components necessary to interface with 3.3V PECL and LVDS logic. The board can be connected directly to the output of a clock-anddata-recovery circuit (such as the MAX3675) and to the input of an LVDS device (such as an overhead termination circuit). A signal generator or stimulus system can be used with an oscilloscope, to evaluate the MAX3681’s basic functionality. 2 GND +3.3V J3 SD- SCLK- SMA SMA SCLK+ J1 SMA SD+ SMA J4 J2 L1 56nH C4 0.1µF C3 0.1µF C2 0.1µF C6 2.2µF R7 130Ω R5 130Ω R3 130Ω R1 130Ω R8 82Ω R6 82Ω R4 82Ω R2 82Ω VCC C7 0.1µF C8 100pF THIS SYMBOL REPRESENTS A TRANSMISSION LINE OF CHARACTERISTIC IMPEDANCE Z0 = 50Ω C5 33µF 6.3V VCC VCC VCC VCC C1 0.1µF 1 2 3 4 5 6 7 8 9 10 11 12 C9 100pF J6 SYNC+ SYNCVCC GND C10 100pF SMA SYNC+ J5 VCC MAX3681 VCC SD+ SDVCC SCLK+ SCLKVCC 24 23 22 21 20 19 18 17 16 15 14 13 C11 100pF SMA SYNC- GND PCLK+ PCLK- PD1PD0+ PD0- PD3+ PD3GND PD2+ PD2PD1+ VCC R13 100Ω R12 100Ω R9 100Ω R11 100Ω R10 100Ω J15 J13 J11 J9 J7 J16 PCLK+ SMA J14 SMA PD0+ J12 SMA PD1+ J10 SMA PD2+ J8 SMA PD3+ SMA PCLK- SMA PD0- SMA PD1- SMA PD2- SMA PD3- Evaluates: MAX3681 MAX3681 Evaluation Kit Figure 1. MAX3681 EV Kit Schematic _______________________________________________________________________________________ MAX3681 Evaluation Kit Evaluates: MAX3681 Figure 2. MAX3681 EV Kit Component Placement Guide—Component Side _______________________________________________________________________________________ 3 Evaluates: MAX3681 MAX3681 Evaluation Kit Figure 3. MAX3681 EV Kit PC Board Layout—Component Side 4 _______________________________________________________________________________________ MAX3681 Evaluation Kit Evaluates: MAX3681 Figure 4. MAX3681 EV Kit PC Board Layout—Solder Side _______________________________________________________________________________________ 5 Evaluates: MAX3681 MAX3681 Evaluation Kit Figure 5. MAX3681 EV Kit PC Board Layout—Power Plane 6 _______________________________________________________________________________________ MAX3681 Evaluation Kit Evaluates: MAX3681 Figure 6. MAX3681 EV Kit PC Board Layout—Ground Plane _______________________________________________________________________________________ 7 Evaluates: MAX3681 MAX3681 Evaluation Kit Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 8 ___________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 © 1996 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.