ICS843034 Datasheet, PDF (1/23 Pages) Integrated Circuit Systems – MULTI-RATE 3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER

Integrated
Circuit
Systems, Inc.
PRELIMINARY
ICS843034
FEMTOCLOCKS™
MULTI-RATE 3.3V, 2.5V LVPECL FREQUENCY SYNTHESIZER
GENERAL DESCRIPTION
The ICS843034 is a general purpose, low phase
ICS
noise LVPECL synthesizer which can generate
HiPerClockS™ frequencies for a wide variety of applications. The
ICS843034 has a 4:1 input Multiplexer from which
the following inputs can be selected: 1 differential
input, 1 single-ended input, or two crystal
oscillators, thus making the device ideal for frequency
translation or frequency generation. Each differential LVPECL
output pair has an output divider which can be independently
set so that two different frequencies can be generated.
Additionally, each LVPECL output pair has a dedicated power
supply pin so the outputs can run at 3.3V or 2.5V. The
ICS843034 also supplies a buffered copy of the reference
clock or crystal frequency on the single-ended REF_CLK pin
which can be enabled or disabled (disabled by default). The
output frequency can be programmed using either a serial or
parallel programming interface.
The phase jitter of the ICS843034 is less than 1ps rms, making
it suitable for use in Fibre Channel, SONET, and Ethernet
applications.
Example applications include systems which must support
both FEC and non FEC rates. In 10Gb Fibre Channel, for
example, you can use a 25.5MHz crystal to generate a
159.375MHz reference clock, and then switch to a 20.544MHz
crystal to generate 164.355MHz for 66/64 FEC. Other
applications could include supporting both Ethernet
frequencies and SONET frequencies in an application. When
Ethernet frequencies are needed, a 25MHz crystal can be
used and when SONET frequencies are needed, the input
MUX can be switched to select a 38.88MHz Crystal.
PIN ASSIGNMENT
FEATURES
• Dual differential 3.3V LVPECL outputs which can be set
independently for either 3.3V or 2.5V
• 4:1 Input Mux:
1 differential input
1 single-ended input
2 crystal oscillator interfaces
• CLK, nCLK pair can accept the following differential
input levels: LVPECL, LVDS, LVHSTL, HCSL, SSTL
• TEST_CLK accepts LVCMOS or LVTTL input levels
• Output frequency range: 35MHz to 750MHz
• Crystal input frequency range: 12MHz to 40MHz
• VCO range: 560MHz to 750MHz
• Parallel or serial interface for programming feedback
divider and output dividers
• RMS phase jitter at 333.33MHz, using a 22.222MHz
crystal (12kHz to 20MHz): 0.80ps (typical)
• Supply voltage modes:
LVPECL outputs (core/outputs):
3.3V/3.3V
3.3V/2.5V
REF_CLK output (core/outputs):
3.3V/3.3V
• 0°C to 70°C ambient operating temperature
• Industrial temperature available upon request
• Available in both, Standard and RoHS/Lead-Free compli-
ant packages
M8
NB0
NB1
NB2
OE_REF
OE_A
OE_B
VCC
NA0
NA1
NA2
VEE
48 47 46 45 44 43 42 41 40 39 38 37
1
36
2
35
3
34
4
ICS843034
33
5
48-Pin LQFP
32
6 _{7mm x 7mm x 1.4mm} 31
7
package body
30
8
Y Package
29
9
Top View
28
10
27
11
26
12
25
13 14 15 16 17 18 19 20 21 22 23 24
XTAL_OUT1
XTAL_IN1
XTAL_OUT0
XTAL_IN0
TEST_CLK
SEL1
SEL0
VCCA
S_LOAD
S_DATA
S_CLOCK
MR
The Preliminary Information presented herein represents a product in prototyping or pre-production. The noted characteristics are based on initial
product characterization. Integrated Circuit Systems, Incorporated (ICS) reserves the right to change any circuitry or specifications without notice.
843034AY
www.icst.com/products/hiperclocks.html
REV. A JULY 25, 2005
1