ICS843204I Datasheet, PDF (1/16 Pages) Integrated Circuit Systems – FEMTOCLOCKS™ CRYSTAL-TO-3.3V LVPECL FREQUENCY SYNTHESIZER

FEMTOCLOCK™ CRYSTAL-TO-
3.3V LVPECL FREQUENCY SYNTHESIZER
ICS843204I
GENERAL DESCRIPTION
The ICS843204I is a 4 output LVPECL Synthesizer
ICS
optimized to generate Gigabit Ethernet and SONET
HiPerClockS™ _{reference clock frequencies and is a member of the}
HiPerClocks^TM family of high performance clock
solutions from IDT. Using a 19.44MHz and 25MHz,
18pF parallel resonant crystal, 155.52MHz and 156.25MHz
frequencies can be generated. The ICS843204I uses IDT’s
FemtoClock^TM low phase noise VCO technology and can achieve
1ps or lower typical RMS phase jitter. The ICS843204I is pack-
aged in a 48-pin TSSOP package.
FEATURES
• Four 3.3V LVPECL outputs
• Selectable crystal oscillator interface
or LVCMOS/LVTTL single-ended input
• Supports the following output frequencies: 155.52MHz
and 156.25MHz
• VCO range: 560MHz - 680MHz
• RMS phase jitter @ 155.52MHz, using a 19.44MHz crystal
(12kHz - 20MHz): 0.98ps (typical)
• RMS phase jitter @ 156.25MHz, using a 19.44MHz crystal
(1.875MHz - 20MHz): 0.52ps (typical)
• Full 3.3V supply mode
• -40°C to 85°C ambient operating temperature
• Available in both standard (RoHS 5) and lead-free (RoHS 6)
packages
BLOCK DIAGRAM
nPLL_BYPASS_A ^Pullup
IN_SELA ^Pullup
CLK0 ^Pulldown
25MHz
XTAL_IN0
XTAL_OUT0
OSC
nPLL_BYPASS_B ^Pullup
IN_SELB ^Pullup
CLK1 ^Pulldown
19.44MHz
XTAL_IN1
XTAL_OUT1
OSC
PLL
÷4
156.25MHz
625MHz
SELA0
OEA0
0
1
SELA1
OEA1
0
1
QA0
nQA0
QA1
nQA1
PLL
÷4
155.52MHz
622.08MHz
SELB0
OEB0
0
1
SELB0
OEB1
0
1
QB0
nQB0
QB1
nQB1
PIN ASSIGNMENT
nQA1 1
QA1 2
nQA0 3
QA0 4
nc 5
VCCO_A 6
SELA1 7
SELA0 8
nPLL_BYPASS_A 9
nc 10
nc 11
nc 12
nc 13
XTAL_IN1 14
XTAL_OUT1 15
CLK1 16
IN_SEL_B 17
nPLL_BYPASS_B 18
VCCO_B 19
nc 20
QB0 21
nQB0 22
QB1 23
nQB1 24
48 IN_SEL_A
47 CLK0
46 XTAL_IN0
45 XTAL_OUT0
44 nc
43 VEE
42 OEA0
41 OEA1
40 VCC
39 VCCA_A
38 nc
37 nc
36 SELB0
35 VEE
34 OEB0
33 OEB1
32 VCC
31 SELB1
30 VCCA_B
29 nc
28 nc
27 nc
26 nc
25 nc
ICS843204I
48 Lead TSSOP
6.1mm x 12.5mm x 0.925mm
package body
G Package
Top View
IDT^™ / ICS^™ 3.3V LVPECL FREQUENCY SYNTHESIZER
1
ICS843204AGI REV. A MARCH 18, 2009