Since about 8 years we are employng CC1000 as tx/rx chip inside a product. We have TX and RX frequency of 433.3MHz
and reference frequency of 3.6864MHz; L101 is 33nH.
In our recent production we are observing many defective pieces.
We analyzed the problem and found faults in the calibration phase (performed as in fig. 14 of the data sheet). At normal ambient temperature and 3.0V supply the defective products calibrate in tx or rx mode with TEST0 values in the 0x00 .. 0x03 range (TEST2 is 0x15 .. 0x18).
When the device is operating under battery and variable temperatures, often calibration fails.
We tried to change L101 to 27nH, obtaining the calibration with TEST0 = 0x0C .. 0x0F, that seems too near to the other side of the useful range.
Any suggestions-solutions?
Many thanks
Dino
