Comparison of LDO and level shifter

I am working on a project and need to convert 12V to 3.3 V. From what I understand, I can use a level shifter or an LDO. I wanted to know the advantages and disadvantages of using one over the other and best situation/scenarios to use each one. Also I believe an LDO is a buck converter( voltage step down only) while a level shifter can be buck or boost.

Re: LDO vs Level shifter

Dear Hassan
Hi
Why not a simple LM2576 ? it has several types , such as 3.3 volts /5 volts /12 volts ...... ?
Best Wishes
Goldsmith

Re: LDO vs Level shifter

The main benefit of an LDO over a buck converter is lower noise. However, the efficiency is worse especially for large voltage drops. 12 V to 3.3 V implies an efficiency of 28% for the LDO, vs 80-90% for the buck.

Re: LDO vs Level shifter

Dear pstuckey
Hi
Of course if we don't put a good filter in out put the out put will be noisy . but if we put a good filter ( 4 order ) it will be incredible . isn't it ?
Best Regards
Goldsmith

Re: LDO vs Level shifter

Yes, although if good efficiency and good noise performance were required, I would use a switcher to drop most of the voltage then use the LDO to regulate to the final voltage. So in this case the LDO is basically the output filter.

Re: LDO vs Level shifter

So in this case the LDO is basically the output filter.

Click to expand...

What you are referring to ? an LDO after our SMPS ?!
Consider that we have a filter . a differential filter at the out put . what will happen ? any noise can't go through out put . any . because the attenuate ratio is pretty high .

Re: LDO vs Level shifter

I believe I need to provide more detail

I am interfacing a CANBUS to a development board. The CANBUS signals are at 12V but the board needs 3.3V. Hence to convert the incoming data from 12V to 3.3V hence fast switching response on incoming data logic signals is vital. Furthermore, to power the development board I am using a 12 V wall adapter but I need to convert to 3.3 V and voltage regulate it.

As far as my understanding goes I need a level shifter for fast switching but a voltage regulator to keep supply voltage constant at 3.3V . Correct me if I am wrong. Also most datasheets I find are DC to DC buck converter or step down converter, hardly any that say "level" shifter/translator in their title. Are the DC/DC buck converter and step down converter level shifters or buck voltage regulators?. Almost all datasheets I find have high efficiency and low noise making it extremely confusing for me to differentiate.

Re: LDO vs Level shifter

please refer to https://www.edaboard.com/threads/229917/

Alex

Re: LDO vs Level shifter

To power the board I need to voltage translate from 12V to 3.3V and regulate 3.3V. In this case I need a voltage translator+ regulator. So can I use DC/DC or step down buck converter as level shifter+voltage regulator for both the CANBUS(need level shifting) data signals and for powering the board(need level shifting+voltage regulation)

Three example parts are below, can you please identify whether it would be a good idea to use either one for powering the board and level shifting the CAN signals

**broken link removed**

LM2576

MC14504B