Knowledge Base

FSK Bit rate and BW

According to datasheet page43, when using with FSK, BR is calculated as belows:

BR = FXOSC * 32/Bit rate

if FXOSC is 32M and Bit rate is 600bps, then BR equals to 1,706,667 .

At P.43, Bandwidth(BW) has to be larger than a calculated value:
2*Fdev + BR < BW
If Fdev = 800 Hz,
Then Bandwidth would require to be larger than 1.8MHz. but the allowed maximum BW is only 467kHz.
Does that mean the smaller the bit rate, the higher the bandwidth required?
Is there anything wrong on the calculation?

I also tried SX1261 Calculator Tool with the same setting (Fdev = 800, bit rate = 600), The Rx Bandwidth can be selected with 4.8kHz. Once I change the bit rate to 100,000bps, then smallest Rx bandwidth I can choose is 117.3kHz.

It seems the bandwidth calculation of the formula is contradict to the SX1261 Calculator Tool.
I want to know which one is correct and how to calculate the Bandwidth required. Thanks.