What are the different ways to change 5v DC to 3.3v DC?

I can think of voltage divider using resistors, voltage drop using diodes, DC-DC converter, diode with resistor combination, voltage regulator.

What are the pros and cons of each? Are there some methods I am missing out on? Why do we even need DC-DC converters when much simpler methods exist?

I can think of voltage divider using resistors, voltage drop using diodes, DC-DC converter, diode with resistor combination, voltage regulator.

What are the pros and cons of each? Are there some methods I am missing out on? Why do we even need DC-DC converters when much simpler methods exist?

Click to expand...

Hi
It depends on how much current you need ! mention some values as your required current then i can introduce gang of ways .
Best Wishes
Goldsmith

matrixofdynamism said:

I can think of voltage divider using resistors, voltage drop using diodes, DC-DC converter, diode with resistor combination, voltage regulator.

What are the pros and cons of each? Are there some methods I am missing out on? Why do we even need DC-DC converters when much simpler methods exist?

Click to expand...

Voltage divider:
Simple. Only two components required. However, it can only be used as reference and can't really supply any (much) current.

Voltage drop using diodes:
Again simple. Just diodes. Disadvantage is loss in diodes.

DC-DC Converter:
More complex. More expensive. But greater efficiency (usually). Can supply very high current.

LDO regulator:
Simple. More expensive than voltage divider and diode drop methods but cheaper than DC-DC converter (usually). Can supply high current.

Hope this helps.
Tahmid.

What about a resistor, transistor & zener diode?

I'd go with the LDO option; a single-component, cheap solution.

hmm, so it comes down to current that we need and the stability. I was wondering about this and thus I posted a question. It is just a general question, I am not making a circuit as of yet.
So why do we even need DC-DC converters when we can just use regulators or a diode (perhaps a zenner) with resistors? After all DC-DC converters are quite complex things, why do people even need them when there are such easier and cheaper methods available?

It mainly has to do with the low losses and the high efficiency. You won't get much of a benefit from 5V to 3.3V since the voltage gap is so small. The advantages would be far more noticeable if your input voltage was greater than, say, 9V.