5v from 9v Battery?

[muh_j18]

hi,
i'm working on a project where i'm using a ttl 7400 ic which need +5v Vcc, how can i use 5v from a battery 9v, variable resistor works?
thanks

 

[MATLABdude]

hi,
i'm working on a project where i'm using a ttl 7400 ic which need +5v Vcc, how can i use 5v from a battery 9v, variable resistor works?
thanks

That really doesn't work too well if you're drawing a lot of current, or something that has a lot of variable current draw. It's a lot easier to use a linear voltage regulator, something like an LM7805 (lots of companies make these--National Semiconductor, Texas Instruments, On Semiconductor, etc. etc.) They're cheap and pretty reliable.