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dc1954af
DEMO MANUAL DC1954A
Description
LTC6954
Low Phase Noise, Triple Output Clock
Distribution Divider/Driver
Demonstration Circuit 1954A features the
LTC
®
6954
, a
Low Phase Noise, Triple Output Clock Distribution Divider/
Driver.
There are four options of the DC1954A, one for each ver-
sion of the LTC6954. Table 1 summarizes the available
DC1954A options.
The DC1954A LVPECL outputs are AC-coupled 50Ω
transmission lines making them suitable for driving 50Ω
impedance instruments. The LVDS/CMOS outputs of the
DC1954A are terminated with a 100Ω differential resistor
and are DC-coupled. All differential input and outputs have
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and EZSync
is a trademark of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
0.5" spaced SMA connectors. The LTC6954’s EZSync™
function is made available via a turret and an SMA con-
nector.
A DC590 USB serial controller board is used for SPI
communication with the LTC6954, controlled by the
supplied LTC6954_GUI software.
Design files for this circuit board are available at
http://www.linear.com/demo/DC1954A
Figure 1. DC1954A Connections
Ribbon
cable
connection
to DC590
OUT0 Outputs, SMA
LTC6954‐1/‐2/‐3
LVPECL, AC coupled
LTC6954‐4
LVDS/CMOS, DC coupled
3.3V DC Supply,
banana jack &
turret
IN Inputs, SMA
AC coupled
GND, banana
jack & turret
OUTxSEL Inputs, Headers
For LVPECL OUTPUTS:
H=IBIAS ON; L=IBIAS OFF
For LVDS/CMOS OUTPUTS:
H=LVDS; L=CMOS
Temperature
monitoring diode, turret
EZSync
TM
SYNC Input,
SMA & turret
OUT1 Outputs, SMA
LTC6954‐1/‐2
LVPECL, AC coupled
LTC6954‐3/‐4
LVDS/CMOS, DC coupled
OUT2 Outputs, SMA
LTC6954‐1
LVPECL, AC coupled
LTC6954‐2/‐3/‐4
LVDS/CMOS, DC coupled
