Solid State Guitar Amp Forum | DIY Guitar Amplifiers
Solid State Amplifiers => Amplifier Discussion => Topic started by: NPreston on September 07, 2017, 09:27:50 PM
A friend gave me a Fender Frontman 15G to tackle. Found the TDA2050 is toast.. pulls down the rails to about +/- 2 volts (at least the fuse didn't blow..) IN any case I've been reading up on using a LM1875 as a replacement as the TDA2050 is no longer made.. Any advice on this as a replacement?? From what I can tell so far it should be a direct replacement.. I don't know the impedance of the speaker as I don't have it, but 1875 datasheet says it can drive down to a 4 ohm load with +/-25 volt rails.. with the old part out the rails measure something like +/-23.8V. Also, as for heat sinking.. there is a little rubber like insulator on the back of the old part. Would it be wise to try to reuse this on a new part? Would it need thermal grease? When searching on Digikey, I can find all sorts of mica and alum/Oxide insulators for TO220 packages, but nothing for TO220-5 which I believe this package is. Any advice or words of caution?? Thanks..
TO220-5 simply means TO220 with five legs. The insulator doesn;t care how many legs it has. The 5 leg is the same width as the 3 leg.
The LM1875 is a drop in for the TDA2050.
The flexible rubbery insulators do not use thermal grease, just the rigid mica insulators use it.
If the insulator is not torn or damaged I would just re-use it.
Thanks for the info!! Much appreciated!