Is the LM2576 really outdated? I know there are tiny ones now that work and higher frequency, making things smaller.
But, can they put out 3A ?
Whoa there, who said anything about 3A? What kind of discrete TTL logic are you talking about powering?
Anyway a quick search reveals pages upon pages of 3A switching regulators in tiny tiny packages and switching in the MHz region, that means tiny inductors and ceramic capacitors.
And it doesn't stop there either...
I have a circuit for the LM2576, which I picked because it had high current output...
But, I did just take a look at the ti.com web page and this one looks pretty good: TPS54339E http://www.ti.com/lit/ds/symlink/tps54339e.pdf
It's a SO-8 style package can use a fairly small 3.3 uH inductor for 5V output and doesn't need an external diode...
This is pretty hard to beat for the price versus time and individual parts costs of actually making a power supply if you need up to 1.5 amps. The other module the Peter mentioned is a great value as well if you need 500 mA or less.
This is pretty hard to beat for the price versus time and individual parts costs of actually making a power supply if you need up to 1.5 amps. The other module the Peter mentioned is a great value as well if you need 500 mA or less.
Yes, I use those 1.5A ones too. It seems these cheaper modules have sprung in the last year or so because I remember looking and looking and not finding anything at this price point so I ended up doing my own at the time.
Switching regulator modules are normally equipped with their own minimum value capacitors to ensure stability but you should always use 104s (0.1uf) on your logic supplies across the loads etc and it never hurts to have a 106 (10uf) tantalum on the that supply but located more conveniently. For the input side you can use an electrolytic and 100uF is still very small. These are just some basic suggestions as this will also depend upon your power source, is it already regulated?, does it have much ripple?, etc.
BTW, using a 104 or even 103 in parallel with a tantalum (low ESR) provides a balance between high-frequency and medium to low-frequency regulation as it is unlikely that one type or value of capacitor does all best.
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But, can they put out 3A ?
Whoa there, who said anything about 3A? What kind of discrete TTL logic are you talking about powering?
Anyway a quick search reveals pages upon pages of 3A switching regulators in tiny tiny packages and switching in the MHz region, that means tiny inductors and ceramic capacitors.
And it doesn't stop there either...
But, I did just take a look at the ti.com web page and this one looks pretty good: TPS54339E
http://www.ti.com/lit/ds/symlink/tps54339e.pdf
It's a SO-8 style package can use a fairly small 3.3 uH inductor for 5V output and doesn't need an external diode...
http://www.digikey.com/scripts/DkSearch/dksus.dll?WT.z_header=search_go&lang=en&keywords=811-2196-5-nd&x=0&y=0&cur=USD
This is pretty hard to beat for the price versus time and individual parts costs of actually making a power supply if you need up to 1.5 amps. The other module the Peter mentioned is a great value as well if you need 500 mA or less.
Right now, I am reading up on how to determine capacitor values and if anyone has any tips on this, please feel free to fill me in on this
BTW, using a 104 or even 103 in parallel with a tantalum (low ESR) provides a balance between high-frequency and medium to low-frequency regulation as it is unlikely that one type or value of capacitor does all best.