Document
PRELIMINARY
Integrated Circuit Systems, Inc.
ICS843031
FEMTOCLOCKS™ CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR
FEATURES
• 1 differential 3.3V LVPECL output • Crystal oscillator interface designed for 18pF parallel resonant crystals • VCO frequency range: 580MHz - 700MHz • RMS phase jitter @312.5MHz (1.875MHz - 20MHz): 0.5ps (typical) • 3.3V operating supply • 0°C to 70°C ambient operating temperature • Industrial temperature information available upon request
GENERAL DESCRIPTION
The ICS843031 is a 1 Gigabit Ethernet Clock Generator and a member of the HiPerClocksTM HiPerClockS™ family of high performance devices from ICS. The ICS843031 can synthesize 1 Gigabit Ethernet, SONET, or Serial ATA reference clock frequencies with the appropriate choice of crystal and output divider. The ICS843031 has excellent phase jitter performance and is packaged in a small 8-pin TSSOP, making it ideal for use in systems with limited board space.
ICS
FREQUENCY TABLE
Inputs Crystal Frequency (MHz) 25.92 26.04166 26.5625 M/N Ratio (Multiplier) 12 12 12 Output Frequency (MHz) 311.04 312.5 318.75
BLOCK DIAGRAM
OE
PIN ASSIGNMENT
VCC XTAL_OUT XTAL_IN VEE 1 2 3 4 8 7 6 5 Q0 nQ0 VCC OE
XTAL_IN
OSC
XTAL-OUT
Phase Detector
VCO
÷2
nQ0 Q0
ICS843031
8-Lead TSSOP 4.40mm x 3.0mm x 0.925mm package body G Package Top View
÷24 (fixed)
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. 843031AG www.icst.com/products/hiperclocks.html REV. A NOVEMBER 29, 2004
1
PRELIMINARY
Integrated Circuit Systems, Inc.
ICS843031
FEMTOCLOCKS™ CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR
Type Power Input Power Input Pullup Description Core supply pin. Cr ystal oscillator interface. XTAL_IN is the input, XTAL_OUT is the output. Negative supply pin. Output enable pin. LVCMOS/LVTTL interface levels. Differential clock outputs. LVPECL interface levels.
TABLE 1. PIN DESCRIPTIONS
Number 1, 6 2, 3 4 5 7, 8 Name VCC XTAL_OUT, XTAL_IN V EE OE nQ0, Q0
Output
NOTE: Pullup refers to internal input resistors. See Table 2, Pin Characterristics, for typical values.
TABLE 2. PIN CHARACTERISTICS
Symbol CIN RPULLUP Parameter Input Capacitance Input Pullup Resistor Test Conditions Minimum Typical 4 51 Maximum Units pF KΩ
843031AG
www.icst.com/products/hiperclocks.html
2
REV. A NOVEMBER 29, 2004
PRELIMINARY
Integrated Circuit Systems, Inc.
ICS843031
FEMTOCLOCKS™ CRYSTAL-TO3.3V LVPECL CLOCK GENERATOR
4.6V -0.5V to VCC + 0.5V 50mA 100mA 101.7°C/W (0 mps) -65°C to 150°C NOTE: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These ratings are stress specifications only. Functional operation of product at these conditions or any conditions beyond those listed in the DC Characteristics or AC Characteristics is not imp.