Semtech LR1121 - Settxparams; Table 9-6: Settxparams Command; Table 9-7: Ramptime Values

LR1121
User Manual Rev 1.1
UM.LR1121.W.APP Mar 2023
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9.5.2 SetTxParams
Command SetTxParams(...) sets the Tx Power and Ramp Time of the selected PA. SetPaConfig(...) must be sent
prior to this command.
• TxPower defines the output power in dBm in a range of:
 - 17dBm (0xEF) to +14dBm (0x0E) by steps of 1dB if the low power PA is selected
 - 9dBm (0xF7) to +22dBm (0x16) by steps of 1dB if the high power PA is selected
 -18dBm (0xEE) to +13dBm (0x0F) by steps of 1dB if the high frequency PA is selected
 If TxPower > +14dBm, the user must select the VBAT supply for the PA using the SetPaConfig command
• RampTime defines the PA power ramping time, which can be from 16 to 304s according to the following table:
A RampTime of 48s allows the best trade-off between a fast RF power establishment and minimum RF spurious emissions,
therefore complying with radio standards.
Table 9-6: SetTxParams Command
Byte 0 1 2 3
Data from Host 0x02 0x11 TxPower RampTime
Data to Host Stat1 Stat2 IrqStatus(31:24) IrqStatus(23:16)
Table 9-7: RampTime Values
RampTime Value Ramp Time in s
SET_RAMP_16U 0x00 16
SET_RAMP_32U 0x01 32
SET_RAMP_48U 0x02 48
SET_RAMP_64U 0x03 64
SET_RAMP_80U 0x04 80
SET_RAMP_96U 0x05 96
SET_RAMP_112U 0x06 112
SET_RAMP_128U 0x07 128
SET_RAMP_144U 0x08 144
SET_RAMP_160U 0x09 160
SET_RAMP_176U 0x0A 176
SET_RAMP_192U 0x0B 192
SET_RAMP_208U 0x0C 208
SET_RAMP_240U 0x0D 240
SET_RAMP_272U 0x0E 272
SET_RAMP_304U 0x0F 304