Frequency generator circuits
General purpose clock generator:
Now a days, the default signal used in electronic systems
is either square wave or pulse generator. The sine wave generator
is hardly used. If sine wave is very essential it can be derived
from the square wave.
One of the most popular IC used to generate clock from Maxim
Integrated Products is MAX9471. Please refer this circuit
below to design a clock generator out of this device. This
device can be used generate clock frequency in the range of
4MHz to 200MHz.

Circuit Diagram (Schematic Diagram)-1
Refer datashher for pin details, package and other detailed
information avaialable at:
http://datasheets.maxim-ic.com/en/ds/MAX9471-MAX9472.pdf
Use this below circuit to convert square wave into sine wave:

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