Features. Data Sheet. Micrel Inc Fortune Drive San Jose, CA USA tel +1 (408) fax + 1 (408)

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1 Precision Low Power 8:1 MUX with Internal Termination and 1:2 LVPECL Fanout Buffer General Description The SY89859U precision low-power 8:1 MUX with internal termination and 1:2 LVPECL fanout buffer evaluation board is designed for convenient set-up and quick evaluation of the device. The evaluation board is designed to interface directly to 50Ω test equipment. Data sheets and support documentation can be found on Micrel s web site at: Features Evaluation board for the SY89859U precision low power 8:1 MUX with internal termination and 1:2 LVPECL fanout buffer Single power supply AC-coupled configuration directly interfaces to 50Ω equipment On-board channel selection dip-switch Related Documentation SY89859U, Precision Low Power 8:1 MUX with Internal Termination and 1:2 LVPECL Fanout Buffer Data Sheet Evaluation Board MLF and MicroLeadFrame are trademarks of Amkor Technology, Inc. Micrel Inc Fortune Drive San Jose, CA USA tel +1 (408) fax + 1 (408) March 2005 M

2 Evaluation Board Description AC-Coupled Evaluation Board The SY89859U is packaged in a 44-pin MLF. The SY89859U evaluation board is designed to operate from a single 2.5V ±5% or 3.3V ±10% power supply and is configured in AC-coupled input and output mode. AC-Coupled Input The high-speed MUX inputs are configured in ACcoupled mode. In AC-coupled mode, signals automatically bias to the DC-operating point set by V T driven by V REF-AC. The high-speed MUX inputs accept standard CML, PECL, LVPECL, and differential signals as small as 100mV (200mVpp) without level shifting or added termination resistors in the signal path. AC-Coupled Output The SY89859U is configured with AC-coupled output mode allowing the board to interface directly to 50Ω lab equipment. DC-Coupled Output The evaluation board can be re-configured in DCcoupled mode by removing the output current setting resistors, and by substituting the output AC-coupling capacitors with 0Ω resistors. For details, see the Evaluation Board Schematic. Unused Output Single-Ended Outputs Unused compliment outputs should be terminated into 50Ω-to-ground. Unused Output Pairs Unused output pairs can be left floating with no impact on jitter. March M

3 Evaluation Board Schematic LVPECL AC-Coupled Evaluation Board I/O R1 R4 C9, C12, C14, C16 AC-Coupled Input/AC-Coupled Output 82Ω 0.1µF AC-Coupled Input/DC-Coupled Output Remove Resistor 0Ω Table 1. AC-Coupled Evaluation Board Power Supply Connections Note: Default setting is AC-Coupled Input/AC-Coupled Output. March M

4 AC-Coupled Evaluation Board Setup 1. Set the voltage supply to: V CC = 2.5V GND = 0V V EE = 0V 2. Drive inputs with a CML, PECL, LVDS signal, or drive the inputs with a V IN 100mV (200mVpp) signal. 3. Select the MUX input by setting the dipswitch, see MUX Truth Table for more details. 4. Observe the outputs. DC-Coupled Evaluation Board Setup 1. Remove R1-R4. 2. Replace C9, C12, C14, and C16 with 0Ω, 0402 resistors. 3. Set the voltage supply to: V CC = 2.5V GND = 0V V EE = ( 0.5V or 1.3V) 4. Drive inputs with a CML, PECL, LVDS, or drive the inputs with a V IN 100mV (200mVpp) signal. 5. Observe the outputs. SEL2 SEL1 SEL0 Output IN IN IN IN IN IN IN IN7 Table 2. MUX Truth Table Evaluation Board Layout PC Board Layout The evaluation board is constructed with Rogers 4003 material, coplanar in design, fabricated to minimize noise, and achieve high bandwidth minimize crosstalk. Layer L1 L2 L3 L4 Description GND and Signal GND V CC GND Table 3. Layer Stack March M

5 Bill of Materials Item Part Number Manufacturer Description Qty. C1 C25, C27 VJ0402G104KXQC Vishay (1) 0.1µF, 25V, 10% Ceramic Capacitor, Size 0402, X7R Dielectric C26, C28 293D685X0010 Vishay (1) 6.8µF, 16V, Tantalum Electrolytic Capacitor, Size B 2 R1 R4 CRCW040282R5F Vishay (1) 82.5Ω, 1/16W, 1% Thick-film Resistor, Size R5 R7 CRCW F Vishay (1) 3kΩ, 1/16W, 1% Thick-film Resistor, Size SMA1 SMA Johnson Components (2) Jack Assembly End Launch SMA 20 SW1, SW2 CKN3054-ND Panasonic (3) 2-Dip Switch 2 U1 SY89859U Micrel (4) Precision Low Power 8:1 MUX with Internal Termination and 1:2 LVPECL Fanout Buffer Notes: 1. Vishay: 2. Johnson Components: 3. Panasonic: 4. Micrel, Inc.: March M

6 Micrel Cross Reference To find an equivalent Micrel part, go to Micrel 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. HBW Support Hotline: Support: HBWHelp@micrel.com 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 products go to Micrel s website at Once in Micrel s website, follow the steps below: 1. Click on Product Info. 2. In the Applications Information Box, choose Application Hints and Application Notes. MICREL, INC FORTUNE DRIVE SAN JOSE, CA USA TEL +1 (408) FAX +1 (408) WEB The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel 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 Micrel Products for use in life support appliances, devices or systems is a Purchaser s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale Micrel, Incorporated. March M