Pull-up or pull-down resistors needed for the SPI Interface with the PocketBeagle?

Hi all,

I am working on connecting an ADXL357 accelerometer using the SPI interface with the PocketBeagle.

I will only have one slave device connected on the SPI bus

My question is: do I need pull-up or pull-down resistors on any of the SPI interface? If yes, where to connect them and which value ranges should these resistors have?

Google results were a bit confusing as I found a lot of explanations.


You shouldn't need them for SPI..

Take a look at mikroe's schematic for the ADXL345



SPI is not an open collector bus like I2C and pullups are not needed

Thank you both for the prompt answer.

Thanks Robert, the schematics helped a lot.

Could somebody please check my first post from 11 days ago with no response.

Why does it need a response, you answered it yourself...

" Due to the dropout behavior of the LDO TL5209, its output voltage
rail SYS_VDD1_3P3V should not be used when the OSD335x is being
powered through VIN_BAT. Please refer to the TL5209 datasheet for


Supplying an IC that requires 3.3V or more with the output of the TL5209 is definitely not the right choice as:
3.7V (min battery voltage) - 0.06V (typical value of the battery switch dropout voltage V_DO,BAT of the PMIC (p. 9)) - 500mV (voltage dropout of the LDO @f ull load of 500mA) = 3.14V
However the 3.14V is inside the range mentioned in the datasheet for supplying the IC (2.7V to 3.6V). That’s why I am still confused.