LM1857T circuit help? Answered
I have been wanting to build a good amp for a while now and i just got a LM1875T. so i put together this circuit diagram: http://imgur.com/ov3Ikd6
also i am running the audio signal thru an LM386 as a pre-amp/buffer before it hits this. i am using a speaker rated at "4ohm 80W"
and i am using a 30V 2A power supply.
#1 the circuit does not run at all if R2 (22k between pin 1 and ground) is there so i removed it for testing. why is it there if it keeps circuit from working?
#2 C8 (100uf capacitor between pin 3 and ground) is reversed? i thought it might have been a typo on the Texas instruments site so i put it normally. nothing happened. so i put it the way they showed it and it worked! but my cap blew 5 min later... (i used a 50v 100uf) so i replaced it with a 200V 147uf capacitor. it started heating up after 1 minute so i disconnected it to come ask. should i use a tantalum 50V capacitor?