ICS844008I-46 Datasheet, PDF (1/15 Pages) Integrated Device Technology – FEMTOCLOCKS CRYSTAL-TO-LVDS CLOCK GENERATOR

FEMTOCLOCKS™ CRYSTAL-TO-LVDS
CLOCK GENERATOR
GENERAL DESCRIPTION
The ICS844008I-46 is a 10Gb Ethernet Clock
ICS
Generator and a member of the HiPerClocks™ family
HiPerClockS™ _{of high perfor mance devices from IDT. The}
ICS844008I-46 can synthesize 156.25MHz or
100MHz with a 25MHz crystal. It has a total of 8
LVDS outputs. The ICS844008I-46 has excellent phase jitter
performance and is packaged in a 32 Lead VFQFN package,
making it ideal for use in systems with limited board space.
ICS844008I-46
FEATURES
• Eight differential LVDS outputs
• Crystal oscillator interface designed for 18pF parallel resonant
crystals
• Supports the following output frequencies:
156.25MHz or 100MHz
• VCO frequency: 625MHz or 600MHz
• RMS phase jitter @ 156.25MHz, using a 25MHz crystal
(1.875MHz - 20MHz): 0.45ps (typical)
• Full 2.5V supply mode
• -40°C to 85°C ambient operating temperature
• Available in lead-free (RoHS 6) packages
FREQUENCY SELECT FUNCTION TABLE
Input
XTAL Frequency
(MHz)
25
25
FREQ_SEL
0
1
FB Divider
÷25
÷24
Output Divider
÷4
÷6
VCO (MHz)
625
600
Output Frequency
(MHz)
156.25 (default)
100
BLOCK DIAGRAM
OE ^Pullup
25MHz
XTAL_IN
OSC
Phase
VCO
÷4
XTAL_OUT
Detector 625MHz or
or
600MHz
÷6
FREQ_SEL ^Pulldown
FB = ÷25 or ÷24
PIN ASSIGNMENT
8 _Q0:Q7
8 _nQ0:nQ7
32 31 30 29 28 27 26 25
Q0 1
24 nc
nQ0 2
23 OE
GND 3 ICS844008I-46 22 GND
Q1 4
32-Lead VFQFN _{21 nQ7}
nQ1 5 ^{5mm x 5mm x 0.925mm} 20 Q7
package body
VDDO 6
K Package
19 VDDO
Q2 7
Top View
18 ^nQ6
nQ2 8
17 Q6
9 10 11 12 13 14 15 16
IDT^™ / ICS^™ LVDS CLOCK GENERATOR
1
ICS844008AKI-46 REV. A MAY 19, 2008