Intel IXP43X manual Network, Recommendations for Crystal Selection, Oscin, 33 KΩ, 10 KΩ, 33.33 MHz

Models: IXP43X

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Figure 14. Clock Oscillator Interface Example

Intel® IXP43X Product Line of Network Processors—Hardware Design Guidelines

Figure 14. Clock Oscillator Interface Example

 

 

 

3.3 V

OSC_IN

OUT

VDD

 

33 KΩ

10 KΩ

 

ON

 

 

 

 

 

 

0.01 µF

 

 

33.33 MHz

OSC_OUT

 

 

 

Intel® IXP43X

 

 

 

Product Line of

 

 

 

Network

 

 

 

Processors

 

 

 

 

 

 

B4111 -005

3.13.3Recommendations for Crystal Selection

The parameters that should be considered while selecting the crystal to be used are:

Frequency

33.33 MHz

 

 

Operation Mode

Fundamental

 

 

Load

18 pF (This is the capacitance value of the discrete component) *Note1

Capacitance

 

 

 

Frequency

+/- 30 ppm

Tolerance

 

 

 

Frequency

 

stability over

+/- 50 ppm

temperature

 

 

 

Effective Series

20 ohm *Note2

Resistance (ESR)

 

 

Drive level

> 100 uW

 

 

Note: 1) The capacitance value here does not include stray capacitance. The design has been simulated to work with load capacitance up to 36pF.

2)This does not include the stray resistance. The design has been simulated to work up to 40 ohm series resistance.

The Rf and Rs may not needed. Please refer to the crystal vendor datasheet for recommendation.

Intel® IXP43X Product Line of Network Processors

 

HDG

April 2007

52

Document Number: 316844; Revision: 001US

Page 52
Image 52
Intel Network, Recommendations for Crystal Selection, Oscin, 33 KΩ, 10 KΩ, 33.33 MHz, Oscout, Intel IXP43X, Processors