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Low Power, 3GHz, 1:2 LVPECL Fanout Buffer / Translator w / Internal Termination

SY89851U Evaluation Board

Low Power, 3GHz, 1:2 LVPECL Fanout Buffer / Translator w / Internal Termination
SY89851U Evaluation Board
General Description
Features
· SY89851U · Single +2.5V or +3.3V power supply · AC-coupled input and output configuration for easy evaluation · Evaluation board re-configurable for DC-coupled output · Fully assembled and tested
Related Documentation
· SY89851U, Low Power, 3GHz, 1:2 LVPECL Fanout Buffer / Translator with Internal Termination Data Sheet
Evaluation Board
August 2004
M9999-082404 hbwhelp@micrel.com or (408) 955-1690
Micrel
SY89851U Evaluation Board
Evaluation Board Description
DC-Coupled Evaluation Board The SY89851U evaluation board can be configured in DC-coupled mode by removing capacitors C8-C11 and replacing the components with 0 resistors.
Interfacing to 50 Lab Equipment
Interfacing to LVPECL Systems
Unused outputs
August 2004
M9999-082404 hbwhelp@micrel.com or (408) 955-1690
Micrel
SY89851U Evaluation Board
Evaluation Board
SY89851U AC-Coupled LVPECL Evaluation Board
Supply Voltage 2.5V / 3.3V 2.5V 3.3V
I / O AC-Coupled Input / AC-Coupled Output
VCC 2.5 / 3.3V 1.2V 1.2V
VEE 0 -1.3V -2.1V
C8-C11 0.1µF 0 0
AC-Coupled Input / DC-Coupled Output AC-Coupled Input / DC-Coupled Output
Table 1. SY89851U Evaluation Board Setup
Note: 1. 2. Default setting. Remove capacitors at C8-C11 and replace with 0 0402 resistors.
August 2004
M9999-082404 hbwhelp@micrel.com or (408) 955-1690
Micrel
SY89851U Evaluation Board
AC-Coupled Evaluation Board Setup
Setting up the Evaluation Board The following steps describe the procedure for setting up the evaluation board: 1. Set VCC to 2.5 or to 3.3V, and GND and VEE to 0V, and turn off the supply. 2. Using a differential signal source set the amplitude to 400mV (single-ended) or 800mV (differential). Set the offset to a positive value, the value of the offset is not critical, since the AC-coupled inputs will automatically bias to the VT voltage. 3. Turn off or disable the outputs of the signal source. 4. Using equal length 50 impedance coaxial cables, connect the signal source to the inputs on the evaluation board. 5. Using equal length 50 impedance coaxial cables, connect the outputs of the evaluation board to an oscilloscope or other lab equipment with internal 50 termination. 6. Enable the signal source and monitor the outputs.
August 2004
M9999-082404 hbwhelp@micrel.com or (408) 955-1690
Micrel
SY89851U Evaluation Board
Bill of Materials
Item C1, C3, C5-C11 C2, C4 J1 J2 J3 SW SMA1-SMA6 U1
Notes: 1. 2. 3. 4. Vishay: www.vishay.com Johnson Components: www.johnsoncomponents.com Digi-Key: www.digikey.com Micrel: www.micrel.com
Part Number VJ0402Y104KXXAT 293D685X0010 111-0703-001 111-0702-001 111-0701-001 CT2182LPST-ND 142-0701-851 SY89851U
Manufacturer Vishay
Vishay(1) Johnson Components(2) Johnson Components(2) Johnson Components(2) Digi-Key (3) Johnson Components(2) Micrel(4)
August 2004
M9999-082404 hbwhelp@micrel.com or (408) 955-1690
Micrel
SY89851U Evaluation Board
Evaluation Board Layout
PC Board Layout The evaluation boards are constructed with Rogers 4003 material and are coplanar in design and fabricated to minimize noise, achieve high bandwidth and minimize crosstalk.
Layer L1 L2 L3 L4 SY89851U GND and Signal GND VCC and VEE GND
Table 2. Layer Stack
August 2004
M9999-082404 hbwhelp@micrel.com or (408) 955-1690
Micrel
SY89851U Evaluation Board
Micrel Cross Reference
Application Hints and Notes
HBW Support
Hotline: 408-955-1690 Email Support: HBWHelp@micrel.com
MICREL, INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http: / www.micrel.com
August 2004
M9999-082404 hbwhelp@micrel.com or (408) 955-1690