813N252DI-02 Datasheet, PDF (1/23 Pages) Integrated Device Technology – Jitter Attenuator & FemtoClock NG Multiplier

Jitter Attenuator & FemtoClock NG^®
Multiplier
813N252DI-02
DATA SHEET
General Description
Features
The 813N252DI-02 device uses IDT's fourth generation
FemtoClock^® NG technology for optimal high clock frequency and
low phase noise performance, combined with a low power
consumption and high power supply noise rejection. The
813N252DI-02 is a PLL based synchronous multiplier that is
optimized for PDH or SONET to Ethernet clock jitter attenuation and
frequency translation.
The813N252DI-02 is a fully integrated Phase Locked loop utilizing a
FemtoClock NG Digital VCXO that provides the low jitter, high
frequency SONET/PDH output clock that easily meets OC-48 jitter
requirements. This VCXO technology simplifies PLL design by
replacing the pullable crystal requirement of analog VCXOs with a
fixed 27MHz generator crystal. Jitter attenuation down to 10Hz is
provided by an external loop filter. Pre-divider and output divider
multiplication ratios are selected using device selection control pins.
The multiplication ratios are optimized to support most common
clock rates used in PDH, SONET and Ethernet applications. The
device requires the use of an external, inexpensive fundamental
mode 27MHz crystal. The device is packaged in a space-saving
32-VFQFN package and supports industrial temperature range.
Pin Assignment
32 31 30 29 28 27 26 25
LF1 ¹
24
• Fourth generation FemtoClock^® NG technology
• Two LVPECL output pairs
• Each output supports independent frequency selection at 25MHz,
125MHz, 156.25MHz and 312.5MHz
• Two differential inputs support the following input types: LVPECL,
LVDS, LVHSTL, HCSL
• Accepts input frequencies from 8kHz to 155.52MHz including
8kHz, 1.544MHz, 2.048MHz, 19.44MHz, 25MHz, 77.76MHz,
125MHz and 155.52MHz
• Crystal interface optimized for a 27MHz, 10pF parallel resonant
crystal
• Attenuates the phase jitter of the input clock by using a low-cost
fundamental mode crystal
• Customized settings for jitter attenuation and reference tracking
using an external loop filter connection
• FemtoClock NG frequency multiplier provides low jitter, high
frequency output
• Absolute pull range: ±100ppm
• Power supply noise rejection (PSNR): -85dB (typical)
• FemtoClock NG VCXO frequency: 2500MHz
• RMS phase jitter @ 156.25MHz, using a 27MHz crystal
(12kHz – 20MHz): 0.6ps (typical)
• RMS phase jitter @ 125MHz, using a 27MHz crystal
(12kHz – 20MHz): 0.65ps (typical)
• 3.3V supply voltage
• -40°C to 85°C ambient operating temperature
• Available in lead-free (RoHS 6) package
V_EE
LF0 ²
23 _nQB
ISET ³
22 _QB
V_EE ⁴
CLK_SEL ⁵
813N252DI-02
21 _VCCO
20 _nQA
V_CC
RESERVED
V_EE
6
7
8
9
19
18
17
10 11 12 13 14 15 16
QA
V_EE
ODASEL_0
32-pin, 5mm x 5mm VFQFN Package
REVISION 1 08/14/15
1
©2015 INTEGRATED DEVICE TECHNOLOGY, INC.