DS80PCI800SQ Datasheet, PDF (36/45 Pages) Texas Instruments – DS80PCI800 2.5 Gbps / 5.0 Gbps / 8.0 Gbps 8 Channel PCI Express Repeater

DS80PCI800
SNLS334E – APRIL 2011 – REVISED MARCH 2012
www.ti.com
POWER SUPPLY BYPASSING
Two approaches are recommended to ensure that the DS80PCI800 is provided with an adequate power supply.
First, the supply (VDD) and ground (GND) pins should be connected to power planes routed on adjacent layers
of the printed circuit board. The layer thickness of the dielectric should be minimized so that the V_DD and GND
planes create a low inductance supply with distributed capacitance. Second, careful attention to supply
bypassing through the proper use of bypass capacitors is required. A 0.1 μF bypass capacitor should be
connected to each V_DD pin such that the capacitor is placed as close as possible to the DS80PCI800. Smaller
body size capacitors can help facilitate proper component placement. Additionally, capacitor with capacitance in
the range of 1 μF to 10 μF should be incorporated in the power supply bypassing design as well. These
capacitors can be either tantalum or an ultra-low ESR ceramic.
Typical Performance Curves Characteristics
640.0
620.0
600.0
580.0
560.0
540.0
520.0
500.0
480.0
460.0
440.0
420.0
0.8
VDD = 2.625V
VDD = 2.5V
VDD = 2.375V
T = 25^oC
0.9
1
1.1
1.2
1.3
VOD (Vp-p)
Figure 8. Power Dissipation (PD) vs. Output Differential Voltage (VOD)
1021
1019
T = 25°C
1016
1013
1010
1007
2.375
2.5
2.625
VDD (V)
Figure 9. Output Differential Voltage (VOD = 1.0 Vp-p) vs. Supply Voltage (VDD)
36
Submit Documentation Feedback
Product Folder Links: DS80PCI800
Copyright © 2011–2012, Texas Instruments Incorporated