8T74S208A-01 Datasheet, PDF (1/19 Pages) Integrated Device Technology – One differential input reference clock

2.5V Differential LVDS Clock Divider and
Fanout Buffer
8T74S208A-01
DATA SHEET
General Description
The 8T74S208A-01 is a high-performance differential LVDS clock
divider and fanout buffer. The device is designed for the frequency
division and signal fanout of high-frequency, low phase-noise clocks.
The 8T74S208A-01 is characterized to operate from a 2.5V power
supply. Guaranteed output-to-output and part-to-part skew
characteristics make the 8T74S208A-01 ideal for those clock
distribution applications demanding well-defined performance and
repeatability. The integrated input termination resistors make
interfacing to the reference source easy and reduce passive
component count. Each output can be individually enabled or
disabled in the high-impedance state controlled by a I²C register. On
power-up, all outputs are disabled.
Features
One differential input reference clock
Differential pair can accept the following differential input levels:
LVDS, LVPECL, CML
Integrated input termination resistors
Eight LVDS outputs
Selectable clock frequency division of ÷1, ÷2, ÷4 and ÷8
Maximum input clock frequency: 1GHz
LVCMOS interface levels for the control inputs
Individual output enabled/ disabled by I²C interface
Output skew: 45ps (maximum)
Output rise/fall times: 370ps (maximum)
Low additive phase jitter, RMS: 96fs (typical)
Full 2.5V supply voltage
Outputs disable at power up
Lead-free (RoHS 6) 32-Lead VFQFN packaging
-40°C to 85°C ambient operating temperature
Block Diagram
IN
nIN
50
f_REF
÷1, ÷2,
÷4, ÷8
50
V_T
FSEL[1:0] ^{Pulldown (2)}
2
SDA ^Pullup
SCL ^Pullup
I²C
8
ADR[1:0] ^{Pulldown (2)}
2
Pin Assignment
Q0
nQ0
Q1
nQ1
ADR1
32 31 30 29 28 27 26 25
1
24
FSEL0
Q2
GND ²
nQ2
Q0 ³
23 _GND
22 _nQ7
Q3
nQ0 ⁴
21 _Q7
nQ3
8T74S208A-01
Q1 ⁵
20 _nQ6
Q4
nQ4
nQ1 6
19 Q6
Q5
nQ5
GND 7
V_DDO 8
18 GND
17 V_DDO
Q6
nQ6
9 10 11 12 13 14 15 16
Q7
8T74S208A-01
nQ7
32-Lead VFQFN, 5mm x 5mm x 0.925mm
8T74S208A-01 REVISION 1 06/15/15
1
©2015 Integrated Device Technology, Inc.