Ya I know. I use it to remove chips at low temp. I usually use a heat gun set at high heat for install. I know u don't like that method but I have found a quick burst of high heat will melt the solder before the internals of the chip have time to heat up. I can't even remember the last time I lost a 21844s chip to heat. The 2110 and 2010 chips are way more sensitive imo. I swear they blow just from looking at them!
You're right. I have no use for hot-air other than helping to desolder massive items, like terminal blocks.
Again, I've never seen one of these ICs go over 5v on pin 2. It's also odd that the other one begins switching before 2v. It sounds like they're defective.
Again, I've never seen one of these ICs go over 5v on pin 2. It's also odd that the other one begins switching before 2v. It sounds like they're defective.
While they're out (if you haven't yet replaced them), confirm that the mute/delay circuit is working correctly.
You'll need a pull-up resistor from the pin 2 pad of the 21844 (connect to the capacitor [c13 and c19] that's connected to that pad to prevent stressing pad 2). A 10k should be a good value. Connect it to the 12v regulator. You can make that connection on the 12v filter cap (connected to pad 7 of the 21844).
The voltage should be at full negative rail while the protect LED is lit (a few seconds) and then rise relatively slowly (a few seconds) towards 12v after the protect LED goes out. When remote is removed, it should immediately drop back to the negative rail.
Check one then move the resistor to the other IC and make sure the timing is the same.
The voltage should be at full negative rail while the protect LED is lit (a few seconds) and then rise relatively slowly (a few seconds) towards 12v after the protect LED goes out. When remote is removed, it should immediately drop back to the negative rail.
Check one then move the resistor to the other IC and make sure the timing is the same.
Is this something that would be on the card or the board because it does the same thing with a different known working card. I think the problem is on the board.
The two SD voltages causing different start times is very odd and I don't see how that could be on the main board because the same signal goes to both SD terminals. The SD transistor simply turns off and the two ICs pull the voltage up internally.
Are you saying that one IC still goes to well over 6v on pin 2?
And the other IC still starts significantly quicker than the other?
Are you saying that one IC still goes to well over 6v on pin 2?
And the other IC still starts significantly quicker than the other?
If the voltage is rising faster on pin 2 of one IC, the capacitor that's connected to it may be out of tolerance.
I'm starting to think it's the same issue as this.
I went ahead and ordered a card
https://www.diyaudio.com/community/threads/twisted-sounds-ts3-5kw-advice.358431/
I went ahead and ordered a card
https://www.diyaudio.com/community/threads/twisted-sounds-ts3-5kw-advice.358431/
Ya but there I think there were alot of boards that had bad cards. I wouldn't be surprised if they were both bad.
Got the replacement card and the both sides start at the same time now but ½ of the amp still heats up. All fets are from the same batch, all drive transistors are new and the card is brand new.
Do the drive waveforms match at the gates of all of the corresponding FETs from one side to the other?
Both sides operating at the same frequency?
Bad inductor?
Both sides operating at the same frequency?
Bad inductor?