Hi Sree, 1) I think you should check the tuning capacitors temp. grade first. In this case you need to use NPO grade. If you are using Y5V, it won't work well when temp. changes a lot. 2) Make sure that the tuning capacitor's value is same as what recommended in MCF5212 app. Notes. 3) If capacitors are OK, you need to check XTAL power consumption and make sure that MCF5212 can drive the XTAL at low temp. Tianqi Li -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of chundi srikanth Sent: Saturday, January 30, 2010 10:18 AM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Query about Oscillator problem Hi Friends, I have designed a board with MCF5212 Processor and it was interfaced to a Pericom (saronix-ecera) NKS5 series quartz crystal. The crystals operating temperature was -40Deg c to 85Deg c. Earlier i tested this board and everything was fine but now because the PLL was not locking and processor was working. So when i observed i noticed that at ambient temperature the crystal clock output was 2V p-p but with decrease in temperature the clock output was decreasing below 0.8V at -40 Deg c. Can you just give me an idea about this problem and what might be the problem in this scenario? Thanks & Regards Sree ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu