Using Semtech SM1262 at +22 dBm "modified to optimize the PA clamping threshold"

Info for Semtech SX1262 permitting operation at 22 dBm

I’m using the Semtech assembly, SX1262DVK1PAS. The datasheet on the device, ‘SX1261/2 Long Range, Low Power, sub-GHz RF Transceiver’,

https://semtech.my.salesforce.com/sfc/p/#E0000000JelG/a/2R000000HT76/7Nka9W5WgugoZe.xwIHJy6ebj1hW8UJ.USO_Pt2CLLo

has information on the rf power operation.

(Note - the datasheet link is on SX1262 | Long Range Low Power LoRa® Transceiver +22dBm | Semtech - click on Datasheets and Resources - it’s the SX1261/SX1262 Datasheet)

The particular section of the manual/datasheet,

15.2 Better Resistance of the SX1262 Tx to Antenna Mismatch, (on page 102)

states that there is a clamping mechanism that causes ‘typically 5 to 6 dB less output power than the expected’.

But a later subsection,

15.2.2 Workaround,

provides the means “modified to optimize the PA clamping threshold”.

Now, I’d like to utilize that, but I don’t wish to push the device too hard. Rather, I’d like to be conservative, “to protect the internal devices and ensure long-term reliability of the chip”, while reaching the 22 dBm output power. But I do wish to be able to use FSK or CW operation at times.

Since the chip size is small (and therefore has lower ‘thermal mass’), the answers to two questions would help.

For operation (at around, say, 25 deg C - or pick a temp that info is available for),

a. how long (seconds) can the unit operate at +22 dBm without problem

b. what is the suggested maximum duty cycle,
Hopefully, the Semtech Team will be able to provide assistance.

Kind regards,

HI George,

I’m not sure this is the best forum for your question as this is primarily for asking questions about how to use Mbed OS and any associated issues…

Regards
Anna