titanium 800.1 repair info

Jeff23spl · Post by **Jeff23spl** » Sat Jan 02, 2010 11:03 pm

hello
i got this amp to repair and the power supply is burned very bad

all the irfz48 are burned and also their pre-driver that i cannot identify
is there a way to get the full part number or a replacement number

actually is Q38-39-40-41 on the amp board

1 is written F D140 A06 and the other match is F D 021 A56

is their any way to know what it is if it is just a standard trasistor with a good gain or a fet etc
thanks

vingasoline · Post by **vingasoline** » Sun Jan 03, 2010 12:00 pm

check mouser PZTA56, PZTA06

Bipolar transistor

Jeff23spl · Post by **Jeff23spl** » Sun Jan 03, 2010 3:51 pm

thanks

how did you figured this out, just by the A06 and A56 ?

it is good to know

i hope to be able to make it play again

vingasoline · Post by **vingasoline** » Sun Jan 03, 2010 6:53 pm

Chances are, with the power supply being that bad, you'll be looking at replacing the pwm controller, most likely SG3525AP -16pin surface mount.. Good luck.

If you decide you would rather sell it than fix it, send me a pm..

Jeff23spl · Post by **Jeff23spl** » Sun Jan 03, 2010 9:06 pm

i replaced the predriver and got 6.5v like a 40-50% duty cycle but it still blew the power irfz instantaneously in a cracking noise. I believe the pwm clock is good because of this 6.5v

maybe the tfo is short ? Or the board....The board fried a little bit when the amp blew because it get too hot and solder melt down to have 2 25v 2200uf capacitor fallen down.....

diodes rectifier are ok but i read my 14v positive to each diode common exit. even with power mosfet irfz removed....I need to figure this out ....

vingasoline · Post by **vingasoline** » Sun Jan 03, 2010 9:54 pm

I wouldn't rule out the pwm.. also check your output transistors/resistors.. Leaking caps

Post by **Jacampb2** » Thu Jan 07, 2010 7:01 pm

Fix what destroyed the power supply in the first place. Did you check the output BJTs? If they fail, they typically fail shorted, and then take out the power supply. If they are okay, the next thought is the power supply fets. The fet's series gate resistor will normally fail along with the fets when they go. If the resistors are open, 33 ohm 1% SMD if memory serves, then the fets will pop again almost immediately on supplying power. There is also a pull down, IIRC 1K SMD resistor on the gate signal to both fet banks, if these are open then the fets will spontaneously self destruct as well.

I have yet to see a SG3525 (the PWM controller in these amps) be blown with the power supply failure. Not saying it could not happen, but I have brought back numerous Ti amps after power supply failure, some with gaping holes in the board, and I have never seen the PWM go with the rest of the supply.

Good luck,
Jason