AMIS-53050 Datasheet, PDF (78/107 Pages) AMI SEMICONDUCTOR – Frequency Agile Transceiver

AMIS-53050 Frequency Agile Transceiver
Data Sheet
6.10.1.7. RF PLL Trim
This register contains the value of the trim from the self calibration. The values written to this register by the PLL calibration can provide
some indication of the quality of the frequency selection. Values at the maximum or minimum allowed for the TX or RX trim function,
even when calibration passes, may indicate (although not necessarily) that a different value for the VCO external LC components could
provide better performance or that a slightly different frequency should be used.
Table 74: RF PLL Trim - 0X27 [39]
Bit Name
State
7
TX Mode PLL
6:4 _{trim value}
111
--000
Comment
Max. VCO trim value from the self calibration
Min. VCO trim value from the self calibration
3
RX Mode PLL
2:0 trim value
111
--
000
Max. VCO trim value from the self calibration
Min. VCO trim value from the self calibration
6.10.1.8. PLL Target Value
This register is used by the AMIS-53050 during self calibration. This is an internal use register with no user-defined function.
6.10.2. Calibrate Quick Start Oscillator
The Quick Start oscillator must be calibrated prior to operations such as sniff or burst transmit. This command will perform an internal
calibration of the oscillator, write the result to the Quick Start trim register, issue a calibration complete flag, as well as a calibration
good/bad indicator. This command can be issued from any valid state that accepts changes in the instructions.
6.10.3. Calibrate 10kHz Oscillator
In any of the idle modes of operation, an internal 10kHz oscillator is used as the timekeeping reference for the interval timers. The
calibrate 10kHz oscillator command will enable the crystal oscillator to create an accurate time base to use for the calibration of this
oscillator, and then perform the calibration and store the result. A cal done and status flag will be issued upon completion of the
calibration. This command can be issued from any valid state that accepts changes in the instructions.
6.10.4. Calibrate PLL
Calibrate the PLL performs a calibration for the PLL in both transmit and receive mode. The PLL status register reports the calibration
value for both modes, as well as the status for the calibration. This command can be issued from any valid state that accepts changes
in the instructions. This calibration is required when the AMIS-53050 is first powered on or returned from a device reset (before a
transmit or receive instruction is issued).
6.10.5. Calibrate LNA
This command turns on the RF receiver chain and optimizes both the LNA output tuning structure and the LNA input matching trim for
maximum signal level on RSSI. This is a calibration typically performed at board assembly in the presence of a known RF signal. The
AMIS-53050 will auto-tune both the input and output internal variable capacitances of the LNA to optimize gain, compensating for the
tolerance of external components for the match.
Note: Only perform this calibration with a known, non-modulated, signal input (the level should be high enough to be above the noise)
input to the AMIS-53050 receiver.
AMI Semiconductor – Jan. 07, M-20639-002
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