Most people aren't fond of ordering from Asia but Taydaelectronics.com was the ONLY place I have ever found KTC1027. I have gotten output mosfets from them that didn't work but never had a problem with their small signal transistors.
I have used a cross that had the EXACT same specs from mouser with a slightly lower power dissipation and they DID NOT work, the amp (orion 2500d) would protect a few moments after the speaker relay would engage. The parts from Tayda worked just fine.
I have used a cross that had the EXACT same specs from mouser with a slightly lower power dissipation and they DID NOT work, the amp (orion 2500d) would protect a few moments after the speaker relay would engage. The parts from Tayda worked just fine.
Does anyone know the correct value of theis resistor? And the wattage it looks like a 1/4 watt to me but i orderd resistors from digikey before that looked liked 1/4 watt and they swore up and down they were 1 watt.
The resistor measures 33 ohms out of the board just wondering if that correct?
The resistor measures 33 ohms out of the board just wondering if that correct?
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That's right. 33 ohms, 1w.
The size of the resistor depends, in part, on the materials that it's made of. Resistors can be smaller if the materials can withstand higher temperatures. When using miniature resistors, you may want to install them standing off of the board a bit. This will prevent damaging the board from the heat and will prevent the solder connections from oxidizing over time.
The size of the resistor depends, in part, on the materials that it's made of. Resistors can be smaller if the materials can withstand higher temperatures. When using miniature resistors, you may want to install them standing off of the board a bit. This will prevent damaging the board from the heat and will prevent the solder connections from oxidizing over time.
KTC1027 and LTA1023
We have tens of thousands of these in stock
Steve Mantz
Zed Audio
Problem with all the Asian class Ds is that they use through hole parts (lots of inductance) and the driver boards cannot supply the peak current for the banks of MOSFETs which themselves are totally the wrong parts due to high Qg, slow rise and fall times and slow body diodes.
We repair these every week and the only way we know to make them reliable is to modify the circuit and use better MOSFETs.
Look at the value of the gate resistors, they are typically 47 ohm with no ability to discharge the gate on turn off.
When they use the IRS21844 the problem is worse as these chips blow all the time due to gate current issues and they are not easy to purchase due to IRs long lead times.
Steve Mantz
Zed Audio
We have tens of thousands of these in stock
Steve Mantz
Zed Audio
Problem with all the Asian class Ds is that they use through hole parts (lots of inductance) and the driver boards cannot supply the peak current for the banks of MOSFETs which themselves are totally the wrong parts due to high Qg, slow rise and fall times and slow body diodes.
We repair these every week and the only way we know to make them reliable is to modify the circuit and use better MOSFETs.
Look at the value of the gate resistors, they are typically 47 ohm with no ability to discharge the gate on turn off.
When they use the IRS21844 the problem is worse as these chips blow all the time due to gate current issues and they are not easy to purchase due to IRs long lead times.
Steve Mantz
Zed Audio
The amplitude doesn't look right for 1v/div. It's more like what I'd expect at 2v/div unless the scope calibration is way off. The resolution of the second photo isn't good enough to make a judgment on the signal. If the FETs aren't getting hot and it's producing all of the various voltages (regulated for op-amps and for driver board), the drive signal is likely OK.
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