XC5VLX220-2FF1760I Xilinx Inc, XC5VLX220-2FF1760I Datasheet - Page 224

• Manufacturer Part Number: XC5VLX220-2FF1760I
• Description: IC FPGA VIRTEX-5 220K 1760FBGA
• Manufacturer: Xilinx Inc
• Series: Virtex™-5 LXr

Specifications of XC5VLX220-2FF1760I

• Number Of Logic Elements/cells: 221184
• Number Of Labs/clbs: 17280
• Total Ram Bits: 7077888
• Number Of I /o: 800
• Voltage - Supply: 0.95 V ~ 1.05 V
• Mounting Type: Surface Mount
• Operating Temperature: -40°C ~ 100°C
• Package / Case: 1760-BBGA, FCBGA
• For Use With: HW-AFX-FF1760-500-G - BOARD DEV VIRTEX 5 FF1760
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Number Of Gates: -

Chapter 6: SelectIO Resources
224
Controlled Impedance Driver (Source Termination)
Controlled Impedance Driver with Half Impedance (Source Termination)
1.
2.
Alternatively, bidirectional point-to-point lines can use controlled-impedance drivers
(with 3-state buffers) on both ends.
Some I/O standards, such as LVCMOS, must have a drive impedance matching the
characteristic impedance of the driven line. DCI can provide controlled impedance output
drivers to eliminate reflections without an external source termination. The impedance is
set by the external reference resistors with resistance equal to the trace impedance.
The DCI I/O standards supporting the controlled impedance driver are: LVDCI_15,
LVDCI_18, LVDCI_25, LVDCI_33, HSLVDCI_15, HSLVDCI_18, HSLVDCI_25, and
HSLVDCI_33.
X-Ref Target - Figure 6-6
DCI also provides drivers with one half of the impedance of the reference resistors. This
doubling of the reference resistor value reduces the static power consumption through
these resistors by a factor of half. The DCI I/O standards supporting controlled impedance
drivers with half-impedance are LVDCI_DV2_15, LVDCI_DV2_18, and LVDCI_DV2_25.
Figure 6-7
reference resistors R must be 2 × Z
X-Ref Target - Figure 6-7
Driver with termination to V
Driver with termination to V
illustrates a controlled driver with half impedance inside a Virtex-5 device. The
Figure 6-7: Controlled Impedance Driver with Half Impedance
Figure 6-6
Figure 6-6: Controlled Impedance Driver
illustrates a controlled impedance driver in a Virtex-5 device.
www.xilinx.com
Virtex-5 DCI
CCO
CCO
Virtex-5 DCI
0
R/2
R
in order to match the impedance of Z
/2 (Split Termination, Thevenin equivalent)
(Single Termination)
IOB
IOB
UG190_6_04_012706
UG190_6_05_021206
Z
Z
0
0
Virtex-5 FPGA User Guide
UG190 (v5.3) May 17, 2010
0
.