VCXO and Synchronous Ethernet
Jitter Attenuator
ICS810251I
DATA SHEET
General Description
The ICS810251I is a high performance, low jitter/low phase noise
VCXO. The ICS810251i uses a low frequency and low cost pullable
crystal to achieve jitter attenuation for synchronous Ethernet
applications. The ICS810251I can take an input of either 25MHz or
125MHz and produce a single LVCMOS output of 25MHz.
The device is packaged in a small 16 lead TSSOP package and is
ideal for use on space constrained boards typically encountered in
most synchronous ethernet applications.
Applications
• Synchronous Ethernet v0.39a
• End equipment compliant with Std IEEE 802.039a
Features
• One single-ended output (LVCMOS or LVTTL levels),
output Impedance: 15
• Phase jitter attenuation by the VCXO-PLL using a 25MHz pullable
external crystal (XTAL)
• Input frequencies: 25MHz or 125MHz
• Output frequency: 25MHz
• PLL loop bandwidth adjustable by external components
• 25MHz or 125MHz auto input frequency detect
• Full 3.3V or 2.5V supply voltage
• -40°C to 85°C ambient operating temperature
• Available in lead-free (RoHS 6) package
Block Diagram
(External loop
filter inputs.)
LF1 LF0
25MHz
OE
CLK_IN
(25MHz or 125MHz
input frequency auto
detect)
Pre-
divider
(÷1 or ÷5)
PFD CP VCXO
VCXO-PLL
1
0
Q
25MHz
Pin Assignment
PLL_SEL
GND
Reserved
Q
VDDO
OE
VDDA
V DD
1
2
3
4
5
6
7
8
16 CLK_IN
15 V DD
14 LF1
13 LF0
12 GND
11 XTAL_IN
10 XTAL_OUT
9 GND
ICS810251I
16-Lead TSSOP
4.4mm x 5.0mm x 0.925mm
package body
G Package
Top View
ICS810251AGI REVISION B OCTOBER 5, 2012
1
©2012 Integrated Device Technology, Inc.
http://www.Datasheet4U.com
