Texas Instruments CC1020, Manual

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End of calibration
Wait for T
≥
100 us
Calibrate RX frequency register A
(to calibrate TX frequency register
B write MAIN register = D1h).
Register CALIBRATE = 34h
Write MAIN register = 11h:
RXTX=0, F_REG=0, PD_MODE=1,
FS_PD=0, CORE_PD=0, BIAS_PD=0,
RESET_N=1
Write FREQ_A, FREQ_B, VCO,
CLOCK_A and CLOCK_B registers.
PLL_BW = 174 + 16log
2
(f
ref
/7.126)
Start single calibration
Write CALIBRATE register = B4h
Start calibration
f
ref
is the reference frequency (in
MHz)
Yes
Read STATUS register and wait until
LOCK_CONTINUOUS=1
Read STATUS register and wait until
CAL_COMPLETE=1
Calibration OK?
No
End of calibration End of calibration
Wait for T
≥
100 us
Calibrate RX frequency register A
(to calibrate TX frequency register
B write MAIN register = D1h).
Register CALIBRATE = 34h
Write MAIN register = 11h:
RXTX=0, F_REG=0, PD_MODE=1,
FS_PD=0, CORE_PD=0, BIAS_PD=0,
RESET_N=1
Write FREQ_A, FREQ_B, VCO,
CLOCK_A and CLOCK_B registers.
PLL_BW = 174 + 16log
2
(f
ref
/7.126)
Start single calibration Start single calibration
Write CALIBRATE register = B4h
Start calibration
f
ref
is the reference frequency (in
MHz)
Yes
Read STATUS register and wait until
LOCK_CONTINUOUS=1
Read STATUS register and wait until
CAL_COMPLETE=1
Calibration OK?
No
CC1020
www.ti.com SWRS046H – NOVEMBER 2006 – REVISED MARCH 2015
Figure 5-26. Single Calibration Algorithm for RX and TX
5.12.3 PLL Turn-on Time Versus Loop Filter Bandwidth
If calibration has been performed the PLL turn-on time is the time needed for the PLL to lock to the
desired frequency when going from power down mode (with the crystal oscillator running) to TX or RX
mode. The PLL turn-on time depends on the PLL loop filter bandwidth.
Table 5-12 gives the PLL turn-on
time for different PLL loop filter bandwidths.
Copyright © 2006–2015, Texas Instruments Incorporated
Detailed Description 49
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