SE EL34 Plexi-verb

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JazzGuitarGimp
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Joined: Mon Jul 23, 2012 4:54 pm
Location: Northern CA

Re: SE EL34 Plexi-verb

Post by JazzGuitarGimp »

Dave,

LDO's are preferred when you're head voltage is only 0.5V to 2V more than the desired output voltage. For higher head voltages, a standard 78xx or 79xx is typically used. In terms of heat dissipation in the regulator, the equation is the same for LDO linear regulatirs and standard 3-terminal linear regulators: (head voltage - output voltage) x output current. Also, for both types of regulators, the input current equals the output current: it is not a power in equals power out relationship. For example: the head voltage is 20V, output voltage is 5V, output current (and, therefore, input current) is 1A, then:

Output Power = 5W (5V x 1A)
Input Power = 20W (20V x 1A)
Regulator Dissipation = 15W ([20v - 5V] x 1A)

HTH,
Lou
Lou Rossi Designs
Printed Circuit Design & Layout,
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Phil_S
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Location: Baltimore, MD

Re: SE EL34 Plexi-verb

Post by Phil_S »

Thanks very much for being so specific in how to do this. It could be a while 'til I get a round tuit. I foresee life and work getting in the way. I've also got to clear space on my bench to move the scope there. I'm guilty of excess clutter on the bench.
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JazzGuitarGimp
Posts: 2356
Joined: Mon Jul 23, 2012 4:54 pm
Location: Northern CA

Re: SE EL34 Plexi-verb

Post by JazzGuitarGimp »

Phil_S wrote:Thanks very much for being so specific in how to do this. It could be a while 'til I get a round tuit. I foresee life and work getting in the way. I've also got to clear space on my bench to move the scope there. I'm guilty of excess clutter on the bench.
No worries, Phil. I'm not ih a hurry if you're not. And the way, clutter is my middle name. So .i understand your plight. :-)

Cheers,
Lou
Lou Rossi Designs
Printed Circuit Design & Layout,
and Schematic Capture
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