LMK00725 Datasheet, PDF (1/23 Pages) Texas Instruments – Low Skew, 1-to-5, Differential-to-3.3V LVPECL Fanout Buffer

LMK00725
www.ti.com
SNAS625A – SEPTEMBER 2013 – REVISED OCTOBER 2013
Low Skew, 1-to-5, Differential-to-3.3V LVPECL Fanout Buffer
Check for Samples: LMK00725
FEATURES
1
• Five 3.3V Differential LVPECL Outputs
– Additive Jitter: 43 fs RMS (typ) @ 312.5
MHz
– Noise Floor (≥1 MHz offset): -158 dBc/Hz
(typ) @ 312.5 MHz
– Output Frequency: 650 MHz (max)
– Output Skew: 35 ps (max)
– Part-to-Part Skew: 100 ps (max)
– Propagation Delay: 0.37 ns (max)
• Two Differential Input Pairs (pin-selectable)
– CLKx, nCLK Input Pairs can accept
LVPECL, LVDS, HCSL, SSTL, LVHSTL, or
Single-Ended Signals
• Synchronous Clock Enable
• Power Supply: 3.3V ± 5%
• Package: 20-Lead TSSOP
• Industrial Temperature Range: -40ºC to +85ºC
APPLICATIONS
• Wireless and Wired Infrastructure
• Networking and Data Communications
• Servers and Computing
• Medical Imaging
• Portable Test and Measurement
• High-End A/V
DESCRIPTION
The LMK00725 is a low skew, high-performance
clock fanout buffer which can distribute up to five
3.3V LVPECL outputs from one of two inputs, which
can accept differential or single-ended inputs. The
clock enable input is synchronized internally to
eliminate runt or glitch pulses on the outputs when
the clock enable pin is asserted or de-asserted. The
low additive jitter and phase noise floor and ensured
output and part-to-part skew characteristics make the
LMK00725 ideal for applications demanding high
performance and repeatability.
FUNCTIONAL BLOCK DIAGRAM
CLK_EN ^RPU
R_PD
CLK0
nCLK0 ^RPU
0
CLK1 ^RPD
nCLK1 ^RPU
1
CLK_SEL ^RPD
R_PU = Pullup
R_PD = Pulldown
DQ
(1) R_PU = 51 kΩ pullup, R_PD = 51 kΩ pulldown
Figure 1.
Q0
nQ0
Q1
nQ1
Q2
nQ2
Q3
nQ3
Q4
nQ4
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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2013, Texas Instruments Incorporated