4 years, 8 months ago.

sx1276MB1LAS 433MHz Boost up

I am using the following two H/Ws, PingPong Example

1. SX1276MB1LAS (LoRa RF EVK / Low Band port : 433MHz / High Band Port : 915MHz) 2. ST Nucleo L152RE (STM32 MCU EVK)

The measured value using the spectrum analyzer was 13 dBm.

I want to make 433MHz to be over 14dbm.

So I modified it as shown below.

/media/uploads/sunghwan/change.png

And Change void SX1276MB1xAS::SetRfTxPower( int8_t power ) as shown bleow

void SX1276MB1xAS::SetRfTxPower( int8_t power ) { uint8_t paConfig = 0; uint8_t paDac = 0; uint8_t paOcp = 0;

paOcp = RF_OCP_OFF | RF_OCP_TRIM_240_MA; paConfig = 0xCF; paDac = 0x87;

Write( REG_OCP, paOcp ); Write( REG_PACONFIG, paConfig ); Write( REG_PADAC, paDac ); }

However, the measured value was 13.2 dbm using a spectrum analyzer.

What did I do wrong? How do I get 20dBm?

1 Answer

4 years, 8 months ago.

For support relating to Semtech's range of LoRa TXVRs, please register with Semtech's LoRa Developer Portal (https://lora-developers.semtech.com/).

You would need to ensure the match to the PA_Boost port presents the optimum load impedance to the TX at 433 MHz for the maximum output power that is permissible by local regulations. In the first instance, please refer to the published collateal on the Semtech SX1276 webpage: (https://www.semtech.com/products/wireless-rf/lora-transceivers/sx1276), in particular: https://www.semtech.com/uploads/documents/AN1200.19_SX127x_RefDesign_STD.pdf https://www.semtech.com/uploads/documents/SX1276RF1KAS_e269v01a.zip