3.3V DUAL 1:10 PRECISION LVDS FANOUT BUFFER/TRANSLATOR WITH 2:1 INPUT MUX

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3.3V DUAL 1:10 PRECISION LVDS FANOUT BUFFER/TRANSLATOR WITH 2:1 INPUT MUX Precision Edge SY89828L Evaluation Board FEATURES GENERAL DESCRIPTION SY89828L dual 1:10 LVDS fanout buffer Single +3.

1 3.3V DUAL 1:10 PRECISION LVDS FANOUT BUFFER/TRANSLATOR WITH 2:1 INPUT MUX Precision Edge SY89828L Evaluation Board FEATURES GENERAL DESCRIPTION SY89828L dual 1:10 LVDS fanout buffer Single +3.3V power supply AC-coupled configuration for ease-of-use I/O interface includes onboard termination Fully assembled and tested Can be reconfigured for DC-coupled operation The SY89828L evaluation board is designed for convenient setup and quick evaluation of the SY89828L. It allows the user to evaluate the part over its full voltagerange without requiring any modifications to the board. The evaluation board standard configuration is ACcoupled for direct interface to a 50Ω compatible oscilloscope without split supplies. For applications that require a DCcoupled configuration, step-by-step instructions for modifying the board are included. The board is fully assembled and tested. All data sheets and support documentation can be found on s web site at RELATED PRODUCT AND SUPPORT DOCUMENTATION Part Number Function Data Sheet Link SY89828L 3.3V, Dual 1:10 Precision LVDS Fanout Buffer/Translator with 2:1 Input MUX Data Sheet EVALUATION BOARD AC-Coupled Evaluation Board Precision Edge is a trademark of, Inc. 1 Rev.: A Amendment: /0 Issue Date: July 2004

2 EVALUATION BOARD DESCRIPTION Direct 50Ω Scope Interface: AC-Coupled Evaluation Board The SY89828L is packaged in a 64-pin EPAD-TQFP with the EPAD attached to a metal pad on the component side of the board for improved heat dissipation. The high-speed clock inputs, LVDS_CLK and LVPECL_CLK, are brought out to SMA connectors through matched length differential traces. The LVPECL_CLK inputs are AC-coupled on the board and biased with Thevenin Equivalent resistor networks to supply the correct bias for the LVPECL levels. Three of the outputs, Q0, Q9 and Q16, are brought out through SMA connectors from three sides of the chip. These LVDS outputs are AC-coupled for direct connection to an oscilloscope with a standard 50Ω termination to Ground. The LVTTL/ CMOS control inputs OE and CLK_SEL are connected to a dipswitch on the board to allow the different modes to be conveniently selected. DC-Coupled Evaluation Board For DC-coupled operation, the board can be modified to use a direct connection to the differential inputs from a signal source such as an Agilent 8133A signal generator. The common mode voltage levels for the inputs would need to be set differently for the LVPECL inputs. These levels are specified in the DC-Coupled Evaluation Board Set-up section. The outputs will still be configured for AC-coupled operation. Step-by-step instructions for modifying an AC-coupled evaluation board for DC-coupled operation is described in Modifying your AC-coupled board for DC-coupled Operation section of this document. S63 S62 C16 C15 Note: Output load resistors R32 R40 and R43 R50 are 0. I I S2 C1 R50 R49 R48 R47 R46 R45 C µF C38 6.8µF C2 S S5 S6 S8 S9 S12 S13 C3 C4 C5 C6 C7 C8 R15 R17 R19 R21 R16 R18 R20 R22 R1 R6 10k SEL2 LVDS_CLKB /LVDS_CLKB VCCI LVDS_CLKA /LVDS_CLKA CLK_SEL1 LVPECL_CLKA /LVPECL_CLKA GND OE1 LVPECL_CLKB LVPECL_CLKB CLK_SEL2 OE2 SEL1 Q0 /Q0 Q1 /Q1 Q2 /Q2 Q3 /Q3 Q4 /Q4 Q5 /Q5 Q6 /Q6 U1 SY89828L /Q19 Q19 /Q18 Q18 /Q17 Q17 /Q16 Q16 /Q15 Q15 /Q14 Q14 /Q13 Q R32 R33 R34 R35 R36 R37 GNDO Q7 /Q7 Q8 /Q8 Q9 /Q9 Q10 /Q10 Q11 /Q11 Q12 /Q12 GNDO R44 R43 R40 R39 R38 C18, C20, C21, C24, C25 are at power pins 4, 17, 32, 49, 64, respectively. C12 C11 O S39 S38 O or I S1 S2 S3 S4 S5 SW Dip-6 C9 C10 O C µF C39 6.8µF S6 S24 S25 Figure 1. AC-Coupled Evaluation Board Schematic I/O I O GND AC-Coupled Input/AC-Coupled Output +3.3V +3.3V 0V Table 1. Evaluation Board Power Supply Connections 2

3 EVALUATION BOARD SET-UP AC-coupled I/O allows the evaluation board to operate from a single 3.3V supply and interface directly to a 50Ω scope. The following steps describe the procedure for setting up the evaluation board. 1. Set up a voltage source for 3.3V and turn off the supply. 2. Connect the GND terminal to the negative side of the power supply. This is the 0V ground potential. 3. Short the I and O terminals together on the board and connect to the positive side of the 3.3V supply. Turn on the power supply and verify that the power supply current is <150mA. 4. Turn off the power supply. 5. Using a differential signal source set the amplitude of each side of the differential pair to 400mV (800mV measured differentially). Set the offset to +1.2V. Turn off or disable the outputs of the signal source. 6. Using equal length 50Ω impedance coaxial cables, connect the signal source to one of the LVDS_CLK inputs on the evaluation board (S2 and S3 or S5 and S6). 7. Using a second differential signal source set the amplitude of each side of the differential pair to 800mV (1600mV measured differentially). Set the offset to a positive value; the value of this offset is not critical, as the AC-coupled inputs will be automatically biased to the correct offset. Turn off or disable the outputs of the signal source. 8. Using equal length 50Ω impedance coaxial cables, connect the signal source to one of the LVPECL_CLK inputs on the evaluation board (S8 and S9 or S12 and S13). 9. Using equal length 50Ω impedance coaxial cables, connect the outputs of the evaluation board (S24, S25, S38, S39, S62 and S63) to the oscilloscope or other measurement device that has an internal 50Ω termination. If not all outputs are to be monitored, the unused outputs must be terminated with 50Ω to ground. 10. Turn on the power. 11. Enable the signal source and monitor the outputs. Refer to the table below. Switch Position Signal Name SY89828L Pin SW1-1 SEL2 1 SW1-2 CLK_SEL1 7 SW1-3 OE1 11 SW1-4 CLK_SEL2 14 SW1-5 OE2 15 SW1-6 SEL1 16 Table 1. SW1 (DIP-6) Switch Settings Note: Switch in ON position sets signal LOW. EVALUATION BOARD LAYOUT PC Board Layout The evaluation boards are constructed with FRA material and are coplanar in design and fabricated to minimize noise, achieve high bandwidth and minimize crosstalk. L1 L2 L3 L4 L5 L6 Signal/GND Impedance GND O Power I Power GND Signal/GND Table 2. Layer Stack 3

4 BILL OF MATERIALS AC-Coupled Evaluation Board Item Part Number Manufacturer Description Qty. C1, C2, C3, C4, C5, VJ0402V104M Vishay (1), 25V, 10% Ceramic Capacitor, Size 0402, 21 C6, C7, C8, C9, C10, X5R Dielectric C11, C12, C15, C16, C18, C20, C21, C22, C23, C24, C25 C28, C29 Vishay (1), 20V, Tantalum Chip Capacitor, Size B 2 C38, C39 293D685X0010 Vishay (1) 6.8µF, 20V, Tantalum Chip Capacitor, Size B 2 J GND Banana Jack, Black 1 J VCCI Banana Jack, Red 1 J Banana Jack, White 1 R1, R2, R3, R4, CRCW F Vishay (1) 10kΩ, 1/16W, 1% Thick-film Resistor, Size R5, R6 R17, R18, R21, R22 CRCW04020F Vishay (1) Ω, 1/16W, 1% Thick-film Resistor, Size R15, R16, R19, R20 CRCW040282R5F Vishay (1) Ω, 1/16W, 1% Thick-film Resistor, Size R23, R27, R29 CRCW04020R00F Vishay (1) 0Ω, 1/16W, 1% Thick-film Resistor, Size R31, R42 R32, R33, CRCW F Vishay (1) 100Ω, 1/16W, 1% Thick-film Resistor, Size R34, R35, R36, R37, R38, R39, R40, R43, R44, R45, R46, R47, R48, R49, R50 S2, S3, S5, S6, S Johnson Components (2) Jack Assembly End Launch SMA 14 S9, S12, S13, S24 S25, S38, S39, S62, S63 SW1 DIP-6 SPST Switch 1 U1 SY89828L, Inc. (3) 3.3V, Dual 1:10 Precision LVDS Fanout Buffer/ 1 Translator with 2:1 Input MUX Notes: 1. Vishay: 2. Johnson Components: 3., Inc.: 4

5 MODIFYING THE AC-COUPLED BOARD FOR DC-COUPLED OPERATION When DC-Coupling is Necessary Interfacing to Another System For applications where AC-coupling of the inputs is not appropriate, the board can be reconfigured for DC-coupled operation. An example where DC-coupling is required is if the input data or clock can be disabled. This would result in a DC-signal at the inputs and the on-board biasing resistors would apply the same level to both the true and complement inputs. Since these inputs are differential this would result in an intermediate non-differential state at the inputs and the outputs would be in an indeterminate condition. This condition can be avoided by reconfiguring the board for DC-coupled operation. Reconfiguring an AC-Coupled Board into a DC- Coupled Board The following procedure details the steps for converting AC-coupled inputs to DC-coupled inputs on the board. 1. Remove resistors R15, R16, R17, R18, R19, R20, R21 and R Remove capacitors C1, C2, C3. C4, C5, C6, C7 and C8 and replace them with 0Ω resistors. DC-COUPLED EVALUATION BOARD SET-UP The following steps describe the procedure for setting up the DC-coupled evaluation board. 1. Set up a voltage source for 3.3V and turn off the supply. 2. Connect the GND terminal to the negative side of the power supply. This is the 0V ground potential. 3. Short the I and O terminals together on the board and connect to the positive side of the 3.3V supply. Turn on the power supply and verify that the power supply current is <150mA. 4. Turn off the power supply. 5. Using a differential signal source set the levels for the LVDS_CLK inputs to be V IL = 1.0V and V IH = 1.4V. 6. Turn off or disable the outputs of the signal source. 7. Using equal length 50Ω impedance coaxial cables, connect the signal source to one of the LVDS_CLK inputs on the evaluation board (S2 and S3 or S5 and S6). 8. Using a second differential signal source set the levels for the LVPECL_CLK inputs to V IL = 1.5V and V IH = 2.3V. Turn off or disable the outputs of the signal source. 9. Using equal length 50Ω impedance coaxial cables, connect the signal source to one of the LVPECL_CLK inputs on the evaluation board (S8 and S9 or S12 and S13). 10. Using equal length 50Ω impedance coaxial cables, connect the outputs of the evaluation board (S24, S25, S38, S39, S62 and S63) to the oscilloscope or other measurement device that has an internal 50Ω termination. If not all outputs are to be monitored, the unused outputs must be terminated with 50Ω to ground. 11. Turn on the power. 12. Enable the signal source and monitor the outputs. BILL OF MATERIALS Modified DC-Coupled Evaluation Board Item Part Number Manufacturer Description Qty. C1, C2, C3, C4 CRCW04020R00F Vishay (1) Replace with 0Ω, 1/16W, 1% Thick-film Resistor, 8 C5, C6, C7, C8 Size 0402 Notes: 1. Vishay: 5

6 HBW SUPPORT Help Line 's HBW Applications helpline is available to assist you. Please call (408) or for assistance. Cross Reference To find an equivalent part, go to s website at and follow the steps below: 1. Click on Dynamic Cross Reference. 2. Enter competitor s part number in the Dynamic Cross Reference field. 3. To download a PDF version of this information, click on the Cross Reference PDF tab. Application Hints and Notes For application notes on high-speed termination on PECL and LVPECL products, clock synthesizer products, SONET jitter measurement, and other High Bandwidth product go to s website at Once in s website, follow the steps below: 1. Click on Product Info. 2. In the Applications Information Box, choose Applications Hint and Applications Note. MICREL, INC FORTUNE DRIVE SAN JOSE, CA USA TEL + 1 (408) FAX + 1 (408) WEB The information furnished by in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by for its use. reserves the right to change circuitry and specifications at any time without notification to the customer. Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser s use or sale of Products for use in life support appliances, devices or systems is at Purchaser s own risk and Purchaser agrees to fully indemnify for any damages resulting from such use or sale. 2004, Incorporated. 6

Precision CML/LVPECL/LVDS 2:1 MUX with Internal Termination and Fail Safe Input

Precision CML/LVPECL/LVDS 2:1 MUX with Internal Termination and Fail Safe Input General Description The SY58609U, SY58610U, and SY58611U evaluation boards are designed for convenient setup and quick evaluation