Need info on optimal Set_PaConfig

[MPend.3]

Reference manual RM0453 and AN5457 - Rev 2 give some info on optimal PA and TxParm settings but the data is incomplete and appears to be inconstant. For example,

Table 2 of AN5457 says for RFO_HP, +14dBm

set paDutyCycle to 0x2 and TxParms to 14.

The ref manual Table 35 says for RFO_HP, +14dBm

set PaDutyCycle to 0x02 and Txparms to 0x16 (dec 22)

So do I set Txparms to 14 or 22?

paDutyCycle for +15dBm RFO_LP are also inconsistent. The ref manual says 0x7 and the ap-note says 0x06.

Further the tables are incomplete. For example, under HP only settings for output powers of 22,20,17,14 are provided. I tried to interpolate between values but had issues there. And guidance for power lower the 10 (LP) and 14 (HP) dBm are missing.

Is there a document or guidance with more complete information? Which tables should I believe? The Reference manual or the Ap-Note?

What settings should I use (for example) for LP at 5dBm or other powers below 10/14 dBm. Maybe for powers below a certain value just set paConfig and Txparms to the same value?

Thanks in advance for any guidance.

[Benoit MARCHAND · Accepted solution]

Hello,

As a first comment, PA optimal settings is used to maximize the PA efficiency for the maximum targeted output power.

For a given HW board and PaConfig setting, you can get any Output Power lower than the max by decrementing TxParam/Power (unit is dB).

These tables give recommended settings for the max Output powers allowed by regulations in the different regions (EU,US,China, ...).

Optimal Setting logic is mainly to reduce PA dutyCycle while keeping Power to a maximum.

If you want to optimize to 5dBm, you can set an Optimal Setting with a minimal DutyCycle and a Power probably around 0xA (ie, not maximal).

You can also use any recommended setting and just decrease Power.

Concerning inconsistencies between RM0453 and AN5457, yes, you're right. RM0453 is the latest updated. Please consider it as the reference. We'll realign these 2 documents.

Best Regards,

Benoit