AMIS-53050 Datasheet, PDF (48/107 Pages) AMI SEMICONDUCTOR – Frequency Agile Transceiver

AMIS-53050 Frequency Agile Transceiver
Data Sheet
Fraction is the value to be used in the RF frequency 2, 1 and 0 registers. As an example, if the desired RF frequency channel is
903.5MHz,
For this example, the RF divider register is written to 0x26, RF Frequency 2 is written to 0xFE, RF Frequency 1 to 0x95, and RF
Frequency 0 to 0x54.This value +/- 1 is fed directly to the PLL as N0 and N1. (i.e. if 63, send 64 and 65 to the PLL)
Table 18: RF Divider - 0X05 [5]
Bit
Name
7:0
RF_divide [7:0]
Comment
The divider value is the rounded result of dividing the RF frequency by
24MHz
6.4.1.2. RF Frequency 2
Table 19: RF Frequency 2 = 0X06 [6]
Bit
Name
Comment
7:0
RF_FREQ [23:16] ^{Upper 8 bits of the RF fraction}
6.4.1.3. RF Frequency 1
Table 20: RF Frequency 1 - 0X07 [7]
Bit
Name
Comment
7:0
RF_FREQ [15:8]
Center 8 bits of the RF fraction
6.4.1.4. RF Frequency 0
Table 21: RF Frequency 0 - 0X08 [8]
Bit
Name
Comment
7:0
RF_FREQ [7:0]
Lower 8 bits of the RF fraction
6.4.1.5. Peak Deviation 1
The peak deviation for FSK transmissions is determined by the peak deviation 1 register and the peak deviation 0 register. This value
is also used inside the DFT FSK detector. Calculation of the value for the peak deviation is straightforward:
The result of this equation, converted to Hex, is entered into the peak deviation registers.
Table 22: Peak Deviation 1 - 0X09 [9]
Bit
Name
Comment
7:0
PEAK_DEV [15:8] ^{Upper 8 bits of the peak deviation}
AMI Semiconductor – Jan. 07, M-20639-002
48
www.amis.com