2024-07-01 01:19 PM
I am thinking of powering the IIS2DLPCTR accelerometer VDD rail from a buck converter and wanted to understand if this part uses an internal LDO to step the VDD voltage down to power the internal MEMS block and ADC? Or does it use the supplied VDD directly for this? Trying to decide if it’s necessary to use an external LDO on the VDD rail or if a buck with its ripple voltage will not impact performance.
2024-07-01 01:38 PM
An LDO would only increase the energy consumption of the IIS2DLPC. In addition, an LDO would only be able to partially suppress the ripple of a possibly feeding DCDC if it were specially designed for this purpose. Also, such an LDO would represent a non-negligible cost factor. For these reasons, there is no LDO in the IIS2DLPC.
The applied supply voltage should therefore be largely free of ripple, for which, as mentioned, an external LDO is only rarely suitable and a suitable LC filter should be used.
Does this answer your questions?
Regards
/Peter