Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

how to use an external crystal?????

Status
Not open for further replies.
S

s3034585

Full Member level 4
Full Member level 4
Joined
May 24, 2004
Messages
226
Helped
1
Reputation
2
Reaction score
0
Trophy points
1,296
Activity points
2,087
Hi guys...

I am new to microcontroller based hardware design. In my project i am suppose to design a interface for a micro controller. I need to use an exteranl crystal for clk ref in the micro controller.

can any one pls tell me how to interface an external crystal. i mean how to select one and how to design the interface. wht r the points one need to consider while selecting the components.... where can i get some info about it...

thanks in advance.

tama
 

Which microcontroller?
If it has pins for connecting an external crystal, then the data sheet should provide a recommended circuit and crystal selection info.
 

Please refer the data sheet of specified mocrocontroller
 

Hello s3034585
When you make a project that contains a crystal first of all you are looking at the frequency, temperature drift, and aging, So the first you have to look is the frequency of the crystal second if the project demands accuracy then you have to see the temperature and time drift. At last a crystal by itself can't do oscillations you have to put 2 capasitors which there value it depends from the manufacturer and the crystal frequency. I hope my opinion would be helpful for you.
Bye
 

    S

    s3034585

    Points: 2
    Helpful Answer Positive Rating
hi guys
thanks a lot for ur opinions...

hi tzoupkas the info wht u gave me was exactly what i was looking for... thnks

the micro controller which i am using is mcf5282. guys can u pls provide some adivce on interfacing power supply to a micro controller.

This micro controller has a adc, pll and its core.. so it requires 4 power supplies...

digital vdd/vss
analog vdd/vss (adc)
analog vdd/vss (pll)
vref vrh/vrl(ref for voltage for adc)..

i couldnt get this info in the data sheet... ur opinions will help a lot

thanks tama
 

There is a reference design schematic available at: **broken link removed**

The same schematic is available in Orcad format at: **broken link removed**

There is an additional schematic available at: http://www.axman.com/files/CML5282_SCH_D.pdf

From the above, you should be able to get some idea of ways to handle your problem.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top