MAX3670_09 Datasheet, PDF (1/12 Pages) Maxim Integrated Products – Low-Jitter 155MHz/622MHz Clock Generator

19-2166; Rev 2; 9/09
Low-Jitter 155MHz/622MHz
Clock Generator
General Description
The MAX3670 is a low-jitter 155MHz/622MHz reference
clock generator IC designed for system clock distribution
and frequency synchronization in OC-48 and OC-192
SONET/SDH and WDM transmission systems. The
MAX3670 integrates a phase/frequency detector, an
operational amplifier (op amp), prescaler dividers and
input/output buffers. Using an external VCO, the
MAX3670 can be configured easily as a phase-lock loop
with bandwidth programmable from 15Hz to 20kHz.
The MAX3670 operates from a single +3.3V or +5.0V
supply, and dissipates 150mW (typ) at 3.3V. The operat-
ing temperature range is from -40°C to +85°C. The chip
is available in a 5mm ✕ 5mm, 32-pin QFN package.
Applications
OC-12 to OC-192 SONET/WDM Transport
Systems
Clock Jitter Clean-Up and Frequency
Synchronization
Frequency Conversion
System Clock Distribution
Features
♦ Single +3.3V or +5.0V Supply
♦ Power Dissipation: 150mW at +3.3V Supply
♦ External VCO Center Frequencies (f_VCO): 155MHz
to 670MHz
♦ Reference Clock Frequencies: f_VCO, f_VCO/2, f_VCO/8
♦ Main Clock Output Frequency: f_VCO
♦ Optional Output Clock Frequencies: f_VCO, f_VCO/2,
f_VCO/4, f_VCO/8
♦ Low Intrinsic Jitter: < 0.4ps_RMS
♦ Loss-of-Lock Indicator
♦ PECL Clock Output Interface
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX3670EGJ
-40°C to +85°C
32 QFN-EP*
MAX3670ETJ+
-40°C to +85°C
32 Thin QFN-EP*
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Pin Configuration appears at end of data sheet.
Typical Application Circuit
155MHz
3.3V
142Ω
VCO
K_VCO = 25kHz/V
155MHz
142Ω
REFCLK+
REFCLK-
3.3V
VCCD
VCOIN+
100Ω
VCOIN-
MAX3670
MOUT+
MOUT-
142Ω
142Ω
RSEL
N.C.
VSEL
N.C.
MAX3892
16:1
SERIALIZER
0.01μF
332Ω
4700pF
500kΩ
4700pF
500kΩ
VC
OPAMP-
OPAMP+
POLAR
REPRESENTS A CONTROLLED-IMPEDANCE TRANSMISSION LINE.
GSEL1
N.C.
GSEL2
GSEL3
GND
3.3V
SETUP FOR 10kHz LOOP
BANDWIDTH
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.