joshuacp
Member level 4
I want to design a PLL operating over wide temperature range:-40~85℃.
The key is to design the VCO operating over wide temperature range:-40~85℃.
I used a TCXO for VCO reference frequency. Then how to make sure VCO is operating over wide temperature range:-40~85℃.
For the VCO calibration, I calibrated the VCO at 25℃ and stored the calication configuration in the flash. When the VCO start up at 25℃, VCO could start
up normally. But if the VCO start up at -40℃ or 85℃, it could not start up correctly.
How to solve the problem? Could anyone give me any suggestion?
Thank you very much in advance!
The key is to design the VCO operating over wide temperature range:-40~85℃.
I used a TCXO for VCO reference frequency. Then how to make sure VCO is operating over wide temperature range:-40~85℃.
For the VCO calibration, I calibrated the VCO at 25℃ and stored the calication configuration in the flash. When the VCO start up at 25℃, VCO could start
up normally. But if the VCO start up at -40℃ or 85℃, it could not start up correctly.
How to solve the problem? Could anyone give me any suggestion?
Thank you very much in advance!