VSC8140QR VITESSE [Vitesse Semiconductor Corporation], VSC8140QR Datasheet - Page 11

• Manufacturer Part Number: VSC8140QR
• Description: 2.48832Gb/s 16:1 SONET/SDH Transceiver with Integrated Clock Generator
• Manufacturer: VITESSE [Vitesse Semiconductor Corporation]

VSC8140
Data Sheet
9/6/00
G52251-0, Rev. 4.0
Low-Speed Inputs
voltage is necessary to provide for optimal switching of the inputs. The user can either provide an input voltage
reference from the upstream device (VREFIN), or can use the reference voltage provided from the VSC8140
(VREFOUT). Side-by-side placement of the VREFIN and VREFOUT pins facilitates easy implementation.
mode switch point of an LVPECL DC-coupled signal, and adhere to the DC characteristics as specified by the
Table 3 DC characteristics (V
The incoming low-speed inputs are received by single-ended LVPECL inputs TXIN[15:0]. A reference
For DC or AC operation, the external reference should have a nominal value equivalent to the common-
VREFOUT
Z
VREFIN
O
V
V
C
CC
EE
Figure 15: Termination of Low-Speed LVPECL TXIN[15:0] Inputs
IN
741 Calle Plano, Camarillo, CA 93012 • 805/388-3700 • FAX: [phone]
R1
R2
CM
).
VITESSE
Chip Boundary
VITESSE SEMICONDUCTOR CORPORATION
SEMICONDUCTOR CORPORATION
V
V
CC
EE
= 3.3V
= 0V
Transceiver with Integrated Clock Generator
2.48832Gb/s 16:1 SONET/SDH
R1||R2 = Z
V
CC
R2 + V
R1+R2
o
, R1 = 83
C
for AC operation
EE
IN
R1
TYP = 100nF
= V
BIAS
R2 =125
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