Help:Simple scheme of power conversion from 3.3V to 5V

Hello Gurus, Here I only have a 3.3V power supply , but one component on board needs 5V. So I wonder if there is some simple scheme that could solve this problem. Is it possible only to use some passive components to fulfill such task? Thanks in advance!

If you need small current,use 7404 for resonant,then rectify and filte it.

There aren't free meals,don't you know that?
You couldn't use a passive device.
However,there are some very useful one-chip step-up converters using just one inductor,one capacitor,one shottky diode and maybe some resistors.

alphi said:

If you need small current,use 7404 for resonant,then rectify and filte it.

Click to expand...

Hello alphi,
Thanks for your reply.
Could you explain it in more detail?
Is it possible 7404 output voltage level exceeds its power supply level?
Would do be so kind to post the schematic?

you can go for 74LVCC4245/74LVCC16245 Level converters

If the +5V component draws relatively small current (under, say, 50mA), you could use a charge pump (CP) step-up converter. There are unregulated CPs that simply double their input voltage. There are regulated CPs that have an LDO, so you can get 3.3*2->LDO->5V.

What are you deriving +3.3V from? If the original power source (i.e. batery or AC-DC converter) is above, say, +6V, the easiest way to get +5v in your system is to add a separate LDO for the +5V.

Actually, I have a similar problem myself. My system is powered witha 1-cell Li-ion battery. it's voltage is only +3.7V. But I have an instrumentation amp (InAmp), which requires +4.5V. So now i'm thinking of either using a different InAmp that can work of +3.3V or to add a charge pump.