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dc1216f
DEMO MANUAL DC1216
Description
High Speed ADC
Clock Source
Demonstration circuit 1216 is a low jitter, low noise clock
source for demonstrating high speed ADCs. Each assem-
bly includes a LDO regulator and a high precision VCXO.
Functionally, this circuit uses a linear regulator to provide
a clean 5V to a VCXO at a fixed frequency. This VCXO is
capable of providing a signal which is clean enough to
produce data sheet performance from high speed ADCs.
It is designed to have 50Ω output impedance, but has
provision for other termination resistors if needed.
Table 1. DC1216A Variants
DC1216A VARIANTS
VCXO PART NUMBER
OUTPUT FREQUENCY
DC1216A-A
Crystek 601964
100MHz
DC1216A-B
Crystek 602017
122.88MHz
DC1216A-C
Crystek 602019
80MHz
DC1216A-D
Crystek 601964
100MHz
Note:
DC1216A-A, DC1216A-B and DC1216A-C are optimized to be used
with the data converter demo boards. The DC1216A-D is optimized to
drive the synthesizer demo boards.
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
This circuit also is a model for the clock source of ADCs.
It shows how to properly implement a VCXO correctly to
drive the clock of an ADC. It can be used with a DC1075
to produce lower clock frequencies.
Design files for this circuit board are available at
http://www.linear.com/demo
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