Power Supply TO220 vs TO3?

[Brockr0 at cs.com]

> Now I realize, it is going  to be difficult to pick a heat sink 
> to do this because information on this is difficult to find (does 
> anybody know a good place to get this?).


Micrel's 'Designing with Low-Dropout Voltage Regulators' has a good section 
on thermal management including a few examples on how to select a heat sink.
<A HREF="http://www.micrel.com/_PDF/LDOBk.pdf">http://www.micrel.com/_PDF/LDOB
k.pdf</A>

The most straight forward guide to linear power supply design is probably 
National's old Voltage Regulator Handbook (1982). It clearly explains how to 
spec and select every component in a power supply including custom heat 
sinks. I haven't seen this in any of National's recent literature but it is 
worth reading if you find it.

Others have mentioned this here in the past but it is worth noting again, if 
you are going to use 78xx/79xx parts check out <A 
HREF="http://www.national.com/an/AN/AN-182.pdf">http://www.national.com/an/AN/
AN-182.pdf</A> for transient and reverse polarity protection.

AAVID/Thermalloy have good data sheets for their heat sink and thermal 
management products at <A HREF="http://www.aavidthermalloy.com/atp/atp.html">h
ttp://www.aavidthermalloy.com/atp/atp.html</A>. I don't believe they have a 
parametric search so it does help to have some idea of what you are looking 
for on this site. 

Since you will likely need more than one power supply for your system, build 
or buy a better supply for your VCO's at least. It's worth it in the long run.


Brock Russell