
DATA SHEET
ICS844071AG REVISION B OCTOBER 10, 2012
1
2012 Integrated Device Technology, Inc.
FemtoClock Crystal-to-LVDS Clock
Generator
ICS844071
General Description
The ICS844071 is a Serial ATA (SATA)/Serial Attached SCSI (SAS)
Clock Generator. The ICS844071 uses an 18pF parallel resonant
crystal over the range of 20.833MHz - 28.3MHz. For SATA/SAS
applications, a 25MHz crystal is used and either 75MHz or 150MHz
may be selected with the FREQ_SEL pin. The ICS844071 has
excellent <1ps phase jitter performance, over the 900kHz - 7.5MHz
integration range. The ICS844071 is packaged in a small 8-pin
TSSOP, making it ideal for use in systems with limited board space.
Features
One differential LVDS output
Crystal oscillator interface, 18pF parallel resonant crystal
(20.833MHz – 28.3MHz)
Output frequency range: 62.5MHz – 170MHz
VCO range: 500MHz – 680MHz
RMS phase jitter at 150MHz, using a 25MHz crystal
(900kHz – 7.5MHz): 0.45ps (typical)
Full 3.3V or 2.5V operating supply
0°C to 70°C ambient operating temperature
Available in both standard (RoHS 5) and lead-free (RoHS 6)
packages
Table 1. Common Configuration Table
Block Diagram
Inputs
Output Frequency (MHz)
Crystal Frequency (MHz)
FREQ_SEL
M
N
Multiplication Value M/N
25
0
24
4
6
150
25
1
24
8
3
75
26.041666
0
24
4
6
156.25
26.041666
1
24
8
3
78.125
26.5625
0
24
4
6
159.375
26.5625
1
24
8
3
79.675
OSC
Phase
Detector
VCO
500MHz - 680MHz
M = ÷24 (fixed)
FREQ_SEL
N
0
÷4
1
÷8
Q
nQ
FREQ_SEL
XTAL_IN
XTAL_OUT
Pullup
(Default)
1
2
3
4
8
7
6
5
VDDA
GND
XTAL_OUT
XTAL_IN
VDD
Q
nQ
FREQ_SEL
Pin Assignment
ICS844071
8 Lead TSSOP
4.40mm x 3.0mm x 0.925mm
package body
G Package
Top View