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I wanted know what should be the optimum distance between a microntroller(AT89C51ED2) and a crystal of frequency 11.0592MHz?

user4006
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6 Answers6

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Once again, Atmel app notes to the rescue:

Atmel AVR 8-bit Microcontrollers Application Note - AVR042: AVR Hardware Design Considerations

Crystal/oscillator advice starts on page 13 and on page 16, it recommends a "Short distance between the crystal/capacitors and the MCU". Also, an example layout on page 18 shows how they laid-out the crystal circuit.

StainlessSteelRat
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AngryEE
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    an important thing to note about the layout is that the tuning capacitors should have as close to the same ground as possible. That is they should not be tied to the ground plane through separate vias but tied together and then taken to ground ASAP. – Mark Apr 27 '11 at 15:52
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Microchip recommends <0.5" for their PIC18FxxJxx devices.

Leon Heller
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As close as possible. Provide a ground plane around the oscillator components (crystal + capacitors).

stevenvh
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As short as possible, but don't stress out about it for hobby work.

Toybuilder
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Ensure that your crystal is close to the Micro controller, in fact it should be closer to the Pins of the controller where it will be connected to. And with the capacitors connected, it should work just fine.

As far i know for 8051, there is no distance specified, but closeness is well adviced.

All the best.

Paul A.
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You have to put the crystal as closed as possible of the AT89C51ED2.

Daniel Grillo
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