bluetooth和GSM共用26M晶振

mobilesun

在手机上共用晶振的情况下，设计有什么需要注意的地方，
直接从晶振出26M，或者从transceiver出！

ciscospeed

<P>
Crystal lines should be shirt and have the same length. No signals and no ground in layer 2 below the 26MHz crystal. Normally you will have a 26MHz output from the transceiver</P>[br]<p align=right><font color=red>+3 RD币</font></p>

ciscospeed

<P>for pitching the right crystal there're should some requirements Like the crystal shall be 26MHz AT-cut fundamental mode with the following properties:
Parameter Minimum Maximum Units/Comments
Nominal load capacitance 9 to 11 pF1
Initial frequency error at 25&ordm;C -10 to 10 ppm
Variation over temperature
(with respect to value at
25&ordm;C)
-10 to 10 ppm2
-20&ordm;C to 85&ordm;C
ESR 70 Ohms
Drive level 100
W
Pullability 8 10 ppm/pF</P>

<P align=right><FONT color=red>+3 RD币</FONT></P>

[此贴子已经被feel于2005-12-14 23:21:43编辑过]