I have this amp in, which likely had an over-voltage failure. Owner runs 16v in his vehicle, and noticed all that appears to be wrong in this particular amp is the UCC27324 PS driver IC; which is shorted across half its legs. PS Fets are IRF1404 and appear to have survived.
UCC27324 SOIC8 is only rated for 15v max, and so I guess it failed at 16v supply.
Is there another low side driver IC that may work (such as UCC27289) which will operate at +16v?
Thanks in advance.
UCC27324 SOIC8 is only rated for 15v max, and so I guess it failed at 16v supply.
Is there another low side driver IC that may work (such as UCC27289) which will operate at +16v?
Thanks in advance.
Th 27289 is a h-bridge driver. The original is more like a TC4427. The 4427 can withstand more voltage but less current. There may be a higher current version.
ok I actually found a schematic that shows IR4427
I'm not getting clock on Pads 2 or 4 of that driver at IC5. Has the PIC16F1829 failed? Its a 20 pin SOIC version. What can I do if anything if that microprocessor has failed?
Fan comes on, and lights cycle from Green-Blue-Red.
I'm not getting clock on Pads 2 or 4 of that driver at IC5. Has the PIC16F1829 failed? Its a 20 pin SOIC version. What can I do if anything if that microprocessor has failed?
Fan comes on, and lights cycle from Green-Blue-Red.
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Check for activity on other pins. The clock pins are very sensitive and even a scope with the probe set to 10x will load the clock circuit enough to stop it.
What's the rail voltage at 16v?
What's the charging system voltage for his 16v battery?
I think you can buy a new microcontroller from Taramps.
What's the rail voltage at 16v?
What's the charging system voltage for his 16v battery?
I think you can buy a new microcontroller from Taramps.
I think the PIC16 is dead. I installed a new IR4427 and there is no drive on any input nor outputs. I might call Taramps. Any clues on to what a new PIC16 may cost?
Not sure what his 16v and charging setup is, but he brought me a bunch of amps that likely over volt failed. Most of them I turned away. Thought this one would be easier to fix.
Not sure what his 16v and charging setup is, but he brought me a bunch of amps that likely over volt failed. Most of them I turned away. Thought this one would be easier to fix.
Verison R00 HD 3000 V2
Actually Im thinking this amp may be fixed now? I've honestly passed on most Brazilian amps as most parts for the output stage are hard for me to get... This amp being non-blown I thought would be a nice to learn on.
So, this amp is now powering up with 147vDC across main rectifiers.
What I didn't see/realize, was that the PIC16 was actually showing a very faint signal to the IR4427 - as Perry mentioned was likely voided under probing. The amp was not signaling much at all without FETs in the PS, but when I put the FETs in, I gave the amp about ~6 seconds to 'boot', and it started producing a highly fluctuating signal to the PS fets at 14.4v in.
I'll play with this some more. Thanks.
Actually Im thinking this amp may be fixed now? I've honestly passed on most Brazilian amps as most parts for the output stage are hard for me to get... This amp being non-blown I thought would be a nice to learn on.
So, this amp is now powering up with 147vDC across main rectifiers.
What I didn't see/realize, was that the PIC16 was actually showing a very faint signal to the IR4427 - as Perry mentioned was likely voided under probing. The amp was not signaling much at all without FETs in the PS, but when I put the FETs in, I gave the amp about ~6 seconds to 'boot', and it started producing a highly fluctuating signal to the PS fets at 14.4v in.
I'll play with this some more. Thanks.
It is strange that the R_00 V2 version i have, shows a ucc27324dr as a gate driver.
Without the supply fets on, you have about half a second to see a 10% duty cycle pulse on the gate pads.
Without the supply fets on, you have about half a second to see a 10% duty cycle pulse on the gate pads.
The supply doesn't seem to be regulated. Does it use feedback from the B+ rail to set a limit on the rail voltage?
If not, why is there feedback?
If not, why is there feedback?
I’m not sure what’s going on. Sometimes the amp will have 147v rail, and sometimes it will only have 105v rail.
Reference is negative battery terminal.
It’s like if I let the caps completely discharge it’ll run 147v rail on initial start and 2-3 time after, and the drive signal to the PS fets is all crazy. It’s not really like a regulated signal I’ve seen before. Seems more like static noise. Amperage draw at idle jumps all around from 1-1.5A. Scope can’t lock on signal at all. Ps fets do not get hot. Changing input voltage changes nothing.
Then if I power cycle the amp only with rem several times, rail voltage will become 105vdc, and the drive signal on ps fets become a clear lockable square wave and stable .8A draw.
The amp appears to be passing audio signal to speaker terminals in both scenarios.
Reference is negative battery terminal.
It’s like if I let the caps completely discharge it’ll run 147v rail on initial start and 2-3 time after, and the drive signal to the PS fets is all crazy. It’s not really like a regulated signal I’ve seen before. Seems more like static noise. Amperage draw at idle jumps all around from 1-1.5A. Scope can’t lock on signal at all. Ps fets do not get hot. Changing input voltage changes nothing.
Then if I power cycle the amp only with rem several times, rail voltage will become 105vdc, and the drive signal on ps fets become a clear lockable square wave and stable .8A draw.
The amp appears to be passing audio signal to speaker terminals in both scenarios.
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Some of these amps use a rough regulation where there are only a few steps. Do you see the drive waveform pulse width change abruptly as the 12v supply voltage is varied significantly?
mcu senses rail voltage through R37, R36 and R33 and forms a voltage divider with R40.
Over/under input voltage is sensed by the voltage divider R20 and R21
It seems you have a 2 ohm version there.
Over/under input voltage is sensed by the voltage divider R20 and R21
It seems you have a 2 ohm version there.
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Why did he sometimes have only 105v?
The Taramps have a rail voltage range for 12.6v to 13.5v and the rail voltage is proportional to the change in the 12v supply voltage. It doesn't seem regulated. That's why I asked it it only acted as a limiter.
The reason I was concerned is that the rail voltage may exceed the rated voltage of the output FETs at 16v+ (charging voltage) unless the PIC acts to limit the voltage.
The Taramps have a rail voltage range for 12.6v to 13.5v and the rail voltage is proportional to the change in the 12v supply voltage. It doesn't seem regulated. That's why I asked it it only acted as a limiter.
The reason I was concerned is that the rail voltage may exceed the rated voltage of the output FETs at 16v+ (charging voltage) unless the PIC acts to limit the voltage.
Before we assume 147V as the normal rail voltage (instead of 105V), we need to be sure we talk about the 2 ohm version. (output fets should be irfb4115).
If thats the case, with 14V input, rail voltage should be 146.5V.
So, in this version, there are 3 x 18K resistors in series R37, R36 and R33. The other component of the voltage divider is R40 (1K1).
Maybe, there is a bad soldering there.
If thats the case, with 14V input, rail voltage should be 146.5V.
So, in this version, there are 3 x 18K resistors in series R37, R36 and R33. The other component of the voltage divider is R40 (1K1).
Maybe, there is a bad soldering there.
From the information I have (which may not be identical to what you have), the 2 ohm amp should have:
@12.6v a rail of 140v
@13.5v a rail of 147v
If the owner is running the amp on 16v+, wouldn't that push the 150v outputs above their rated voltage?
@12.6v a rail of 140v
@13.5v a rail of 147v
If the owner is running the amp on 16v+, wouldn't that push the 150v outputs above their rated voltage?
I am 99% sure that they use regulation. I need a few days to get an amp and check.
Rail is only positive, not split, so each fet "sees" half of rail voltage.
Its two half bridge sides in bridged configuration.
They leave input grounds of both irs2092 floating to be able to operate like this.
Taramps used to declare rail voltages with 12.6V input, but not in this cace.
This schematic clearly states 14V input and 136.5V rail.
Rail is only positive, not split, so each fet "sees" half of rail voltage.
Its two half bridge sides in bridged configuration.
They leave input grounds of both irs2092 floating to be able to operate like this.
Taramps used to declare rail voltages with 12.6V input, but not in this cace.
This schematic clearly states 14V input and 136.5V rail.
Look at the outputs when either is fully on.
When the low-side is ON (essentially shorted drain to source), the high-side sees full rail. When the high side is fully ON, the low side sees full rail.
When the low-side is ON (essentially shorted drain to source), the high-side sees full rail. When the high side is fully ON, the low side sees full rail.
Output FETs are IRFB4115. I also notice a resistor jumped across the 2-ohm setting, R71.
R33, R36, R37, and R40 all measure OK. I re-flowed all 5 mentioned resistors. Still need to test more but 147V is holding for now. No more 105V rail. The signal on PS Fets is still showing regulated/static-like, but is actually a bit cleaner now. Will still test.
Perry is correct I believe; as heavily varying supply voltage between 10~16vDC causes the PS FET drive signal to change; sometimes I can see a solid square wave but mostly regulation. Also now; amp is holding precisely 1.6A draw every time.
So far the IR4427 seems to be working fine as a PS Get driver.
Thank you!