User Manual

120
8111A–AVR–05/08
AT86RF231
• Bit [3:0] - XTAL_TRIM
The register bits XTAL_TRIM control two internal capacitance arrays connected to pins XTAL1
and XTAL2. A capacitance value in the range from 0 pF to 4.5 pF is selectable with a resolution
of 0.3 pF.
Table 9-16. Crystal Oscillator Trimming Capacitors
Register Bit Value Description
XTAL_TRIM 0x0
0.0 pF, trimming capacitors disconnected
0x1 0.3 pF trimming capacitor switched on
...
0xF 4.5 pF trimming capacitor switched on