Interesting Comparison

Post by **Eric D** » Thu Aug 12, 2010 3:29 pm

On the left is a BJT (Bipolar Junction Transistor) used in most all PG amps.

On the right is an IGBT (Insulated Gate Bipolar Transistor) from an industrial servo control I am trying to repair.

No one uses IGBTs in amps, but several years back a company did use them for home amps (I happen to own a pair of these home amps). However, the IGBTs in my amps are the same physical size as these ones shown here used in PG amps.

My point though is very powerful devices are out there which could be used in mobile amp applications, especially Class D. Just one of these is capable of tremendous power.

holmis · Post by **holmis** » Thu Aug 12, 2010 3:34 pm

WOW!!

Thats a big nasty transistor....

Post by **ttocs** » Thu Aug 12, 2010 4:21 pm

I do not see much of a difference...

what are the benifits that would hlep it perform better?

Post by **Eric D** » Thu Aug 12, 2010 5:41 pm

Size matters. Especially in the case of heat dissipation. The whole bottom of the IGBT is a metal surface for direct contact to a heatsink.

Most amps have transistors measured in tens of amps of current. These are measured in hundreds of amps of current, or more.

Post by **ttocs** » Thu Aug 12, 2010 5:57 pm

yea I figured those puppies could handle some current.