ORT8850H AGERE [Agere Systems], ORT8850H Datasheet - Page 62

• Manufacturer Part Number: ORT8850H
• Description: Field-Programmable System Chip (FPSC) Eight-Channel x 850 Mbits/s Backplane Transceiver
• Manufacturer: AGERE [Agere Systems]

ORCA ORT8850 FPSC
Eight-Channel x 850 Mbits/s Backplane Transceiver
LVDS Buffer Characteristics
Termination Resistor
The LVDS drivers and receivers operate on a 100
not required. The differential driver and receiver buffers include termination resistors inside the device package, as
shown in Figure 22 below.
LVDS Driver Buffer Capabilities
Under worst-case operating condition, the LVDS driver must withstand a disabled or unpowered receiver for an
unlimited period of time without being damaged. Similarly, when its outputs are short-circuited to each other or to
ground, the LVDS driver will not suffer permanent damage. Figure 23 illustrates the terms associated with LVDS
driver and receiver pairs.
62
LVDS DRIVER
Figure 22. LVDS Driver and Receiver and Associated Internal Components
DRIVER
V
V
OA
OB
100
Figure 23. LVDS Driver and Receiver
A
B
V
V
OA
OB
Figure 24. LVDS Driver
A
B
INTERCONNECT
DEVICE PINS
EXTERNAL
R
V
LOAD
GPD
differential impedance, as shown below. External resistors are
C
B
CENTER TAP
C
A
V
V
OD
AA
BB
= (V
50
50
OA
V
V
IA
IB
– V
RECEIVER
OB
)
LVDS RECEIVER
Agere Systems Inc.
August 2001
Data Sheet
5-8703(F)
5-8704(F)
5-8705(F)