8 Apr
2016
8 Apr
'16
11:50 a.m.
William Donzelli wrote:
Nope, purple ceramic. The heat transfer plate is gold
plated too.
That's what I figured to start with, before reading the
datasheets.
At this point, I think I'll just wait till Monday and work
on other things.
I didn't think so.
Bill
1) The 7805 is
actually a Motorola MC7805CP, date
code 7308 with gold leads. Very hard to exactly
replace.
Is that the big flat plastic package with the wide
flat leads? 1) I have a 12
volt DC supply. 12 volts seems to be
within the VIN range for the 7805s whose data
sheets I've now read. Can I simply apply 12 volts?
Yes, but that regulator might get mighty hot! I would
not do this for fear of cooking the poor thing. 2) Could I
place a resistor in series between the 12V
supply and the 7805 to drop the voltage at the 7805
to somewhere around 8?
Yes, you could do this. Pick an appropriate power resistor,
or use a big wirewound rheostat. 3) If I was to
"tack on" a jumper between VIN and VOUT,
would that protect the 7805 and allow me to power the
circuit with 5 volts?
I would not do this at all.