®
FemtoClock SAS/SATA Clock Generator
ICS843441
DATA SHEET
General Description
Features
The ICS843441 is a low jitter, high performance clock generator. The
ICS843441 is designed for use in applications using the SAS and
SATA interconnect. The ICS843441 uses an external, 25MHz,
parallel resonant crystal to generate four selectable output
frequencies: 75MHz, 100MHz, 150MHz, and 300MHz. This silicon
based approach provides excellent frequency stability and reliability.
The ICS843441 features down and center spread spectrum (SSC)
clocking techniques.
• Designed for use in SAS, SAS-2, and SATA systems
• Center ( 0.33%) Spread Spectrum Clocking (SSC)
• Down (-0.30% or -0.60%) SSC
• Better frequency stability than SAW oscillators
• One differential 3.3V LVPECL output
• Crystal oscillator interface designed for 25MHz
(CL = 18pF) frequency
• External fundamental crystal frequency ensures high reliability
Additional Ordering Information
and low aging
Part/Order Number
Package
Output Frequency
• Selectable output frequencies: 75MHz, 100MHz, 150MHz,
(MHz)
300MHz
843441AG
16 TSSOP
8 SOIC
8 SOIC
8 SOIC
8 SOIC
75, 100, 150, 300
• Output frequency is tunable with external capacitors
• RMS phase jitter: 1.33ps (typical)
843441AM-75
843441AM-100
843441AM-150
843441AM-300
75
100
150
300
• 3.3V operating supply
• 0°C to 70°C ambient operating temperature
• Industrial temperature available upon request
• Available in lead-free (RoHS 6) package
Pin Assignments
Block Diagrams
XTAL_IN
25MHz
XTAL
FemtoClock
Q
OSC
nQ
PLL
XTAL_OUT
ICS843441
8-Lead SOIC, 150 Mil
3.90mm x 4.90mm x 1.375mm package body
SSC Output
Control Logic
Pulldown
Pulldown:
SSC_SEL(1:0)
8- Lead SOIC
M Package
Top View
F_SEL( 1:0) Pullup:Pulldown
Pulldown
nPLL_SEL
VEE
1
2
16
15
14
13
12
11
10
9
F_SEL1
VEE
nPLL_SEL
nQ
Q
VCC
XTAL_IN
XTAL_OUT
XTAL_IN
FemtoClock
25MHz
XTAL
OSC
3
4
5
6
7
8
0
1
PLL
00= 75MHz
SSC_SEL0
01 =100MHz
Q
XTAL_OUT
nc
nc
nc
10 = 150MHz(default)
11 = 300MHz
nQ
F_SEL0
VCC
SSC_SEL1
Pulldown
SSC Output
Control Logic
Pulldown:
SSC_SEL(1:0)
ICS843441
16- Lead TSSOP
16-Lead TSSOP
4.4mm x 5.0mm x 0.925mm package body
G Package
Top View
ICS843441AG REVISION A MAY 18, 2011
1
©2011 Integrated Device Technology, Inc.