at86rf211 ATMEL Corporation, at86rf211 Datasheet - Page 8

• Manufacturer Part Number: at86rf211
• Description: Fsk Transceiver For Ism Radio Applications
• Manufacturer: ATMEL Corporation

8
AT86RF211
Figure 7. Synthesizer Loop Filter Schematic
Note:
The PLL loop filter can be designed to optimize the phase noise around the carrier.
Three configurations can be suggested, regarding the application and channel spacing:
- Narrow band: (14.7 k + 2.2 nF) // 220 pF
- Typical: (3.3 k + 5.6 nF) // 560 pF
- High datarates: (10 k
Fref
FILT1
+ 1 nF) // 100 pF
P F D
C H P
&
VCOIN
VCO
1942C–WIRE–06/02