XRT8010
312MHZ CLOCK & CRYSTAL MULTIPLIER WITH LVDS OUTPUTS
NOVEMBER 2003
REV. 1.0.2
s
DESCRIPTION
The XRT8010 is a monolithic analog phase locked
loop that provides a high frequency LVDS clock
output, using a low frequency crystal or reference
clock. It is designed for SONET/SDH and other low
jitter applications.The high performance of the IC
provides a very low jitter LVDS clock output up to 320
MHz, while operating at 3.3 volts. The XRT8010 has
a selectable 8x or 16x internal multiplier for an
external crystal or signal source. The Output Enable
pin provides a true disconnect for the LVDS output.
The very compact (4 x 4 mm) low inductance
package is ideal for high frequency operation.
Telecommunications Sytems
FEATURES
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156 or 320 MHz Operating Range
•
Low Output Jitter:
s
0.0009 UI
RMS
typical @ 155.52 MHz, per
Telcordia GR-253-CORE for OC-3.
Optimized for 15 to 40 MHz crystals
Uses parallel fundamental mode
•
On Chip Crystal Oscillator Circuit
s
s
APPLICATIONS
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Selectable 8x or 16x multiplier
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Selectable ÷1 or ÷2 LVDS output
•
LVDS output meets TIA/EIA 644A Specification
(2001)
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Gigabit Ethernet
•
SONET/SDH
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SPI-4 Phase 2
•
8x or 16x Clock Multiplier for
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Computer
•
3.3V Low power CMOS: <80 mW typical
•
-40°C to +85°C operating temperature
•
Extremely small 16-lead QFN package
F
IGURE
1. XRT8010 B
LOCK
D
IAGRAM
15-40 M H z
C rys tal
X T A L1
12 - 20 pF
+3.3V
A V
DD
A V
DD
R
EXT
10k
Ω
O V
DD
X TA L2
1 2 - 2 0 pF
X R T 801 0
V oltage R eferenc e
&
B ias G enerator
O sc illator
C ircuit &
Input B uffer
VCO
C alibration Logic
P has e
D etec tor
C harge
P um p
Loop
Filter
S electable
VCO
÷
1 or
÷
2
D iv ider
O U TP
LV D S O utput
O U TN
F eedbac k D iv ider
÷
8 or 16
AGND
(C ry stal)
AG ND
AG ND
FS 1
FS 0
PD
OE
O
GND
Exar
Corporation 48720 Kato Road, Fremont CA, 94538
•
(510) 668-7000
•
FAX (510) 668-7017
•
www.exar.com
EXAR [ EXAR CORPORATION ]
