ICS843442I Datasheet, PDF (1/13 Pages) Integrated Device Technology – FemtoClock™ SAS/SATA Clock Generator

FemtoClock™ SAS/SATA Clock Generator
ICS843442I
DATA SHEET
General Description
The ICS843442I is a low jitter, high performance clock
ICS
generator and a member of the FemtoClock™family of
HiPerClockS™ _{silicon timing products. The ICS843442I is designed}
for use in applications using the SAS and SATA
interconnect. The ICS843442I uses an external,
25MHz, parallel resonant crystal to generate two selectable output
frequencies: 75MHz and 150MHz. This silicon based approach
provides excellent frequency stability and reliability. The ICS843442I
features down and center spread spectrum (SSC) clocking
techniques.
Applications
• SAS/SATA Host Bus Adapters
• SATA Port Multipliers
• SAS I/O Controllers
• TapeDrive and HDD Array Controllers
• SAS Edge and Fanout Expanders
• HDDs and TapeDrives
• Disk Storage Enterprise
Features
• Designed for use in SAS, SAS-2, and SATA systems
• Center (±0.25%) Spread Spectrum Clocking (SSC)
• Down (-0.23% or -0.5%) SSC
• Two differential 3.3V LVPECL output pairs
• Crystal oscillator interface designed for 25MHz (C_L = 18pF)
frequency
• External fundamental crystal frequency ensures high reliability
and low aging
• Selectable output frequencies: 75MHz, 150MHz
• Output frequency is tunable with external capacitors
• RMS phase jitter at 150MHz (integrated from 12kHz to 20MHz):
1.07ps (typical)
• 3.3V operating supply
• -40°C to 85°C ambient operating temperature
• Available in lead-free (RoHS 6) package
Block Diagram
nPLL_SEL ^Pulldown
25MHz
XTAL_IN
XTAL_OUT
OSC
FemtoClock™
PLL
0
1
0 = 75MHz
1 = 150MHz
(default)
F_SEL ^Pullup
SSC_SEL[1:0] ^Pulldown
2
Clock Output
Control Logic
Pin Assignment
VEE 1
16 F_SEL
XTAL_OUT 2
15 VEE
Q0
XTAL_IN 3 14 nPLL_SEL
nQ0
SSC_SEL0 4 13 nQ0
nc 5
12 Q0
Q1
nQ1
nc 6 11 nQ1
nc 7 10 Q1
SSC_SEL1 8
9 VCC
ICS843442I
16-Lead TSSOP
4.4mm x 5.0mm x 0.925mm package body
G Package
Top View
ICS843442AGI REVISION A JUNE 24, 2009
1
©2009 Integrated Device Technology, Inc.