IDT8T49N004I Datasheet, PDF (1/37 Pages) Integrated Device Technology – Fourth Generation FemtoClock NG PLL technology

Programmable FemtoClock^® NG LVPECL/LVDS
Clock Generator with 4-Outputs
IDT8T49N004I
DATASHEET
General Description
The IDT8T49N004I is a four output Clock Generator with selectable
LVDS or LVPECL outputs. The IDT8T49N004I can generate any one
of four frequencies from a single crystal or reference clock. The four
frequencies are selected from the Frequency Selection Table (Table
3A) and are programmed via I²C interface. The four predefined
frequencies are selected in the user application by two frequency
selection pins. Note the desired programmed frequencies must be
used with the corresponding crystal or clock frequency as indicated
in Table 3A.
Excellent phase noise performance is maintained with IDT’s Fourth
Generation FemtoClock^® NG PLL technology, which delivers
sub-400fs RMS phase jitter.
Features
• Fourth Generation FemtoClock NG PLL technology
• Four selectable LVPECL or LVDS outputs via I²C
• CLK, nCLK input pair can accept the following differential input
levels: LVPECL, LVDS, HCSL
• FemtoClock NG VCO Range: 1.91GHz - 2.5GHz
• RMS phase jitter at 156.25MHz (12kHz - 20MHz):
228fs (typical)
• RMS phase jitter at 156.25MHz (10kHz - 1MHz): 175fs (typical)
• Full 2.5V or 3.3V power supply
• I²C programming interface
• PCI Express (2.5Gb/s), Gen 2 (5Gb/s), and Gen 3 (8Gb/s)
jitter compliant
• -40°C to 85°C ambient operating temperature
• Lead-free (RoHS 6) packaging
Pin Assignment
24 23 22 21 20 19 18 17
SCLK 25
16 VCC
SDATA 26
VEE 27
15 V_EE
14 FSEL0
VCCA 28
13 nCLK
LOCK 29
12 CLK
VEE 30
11 VEE
VCC 31
10 XTAL_OUT
CLK_SEL 32
9 XTAL_IN
12 34 5 67 8
IDT8T49N004I
32-Lead VFQFN
5mm x 5mm x 0.925mm package body
3.15mm x 3.15mm E-Pad
NL Package
IDT8T49N004ANLGI REVISION A OCTOBER 15, 2013
1
©2013 Integrated Device Technology, Inc.