Hi All,
I am hoping to have a go at building my own class D amplifier, despite the problems I am probably going to run into with PCB layout and RFI. I am still trying to decide between a traditional PCM with sawtooth generator variety and a self oscillating topology. This will in part be determined by the answers to these questions.
What can I use as a sawtooth generator? I have read on these forums that the old dual opamp circuit is not precise enough. Do I need to use a proper waveform generator IC such as for example the MAX038? I'd rather not...
I would like to use a dual (+/-) supply and I was hoping to use some cheap mosfet driver ICs to drive the FET gates. It is simple enough to run these using a floating supply, but I am unclear on how to implement a level shift or isolation to drive them from a signal which is referenced to ground. It's a shame optocouplers are probably too slow as that would work nicely!
Alternatively I could use one of those fancy bootstrapped high/low side drivers, but again these are made for single supplies and I am unsure how to level shift/isolate the drive signals.
Any advice you can provide on these subjects would be much appreciated!
Many thanks!
Greg.
I am hoping to have a go at building my own class D amplifier, despite the problems I am probably going to run into with PCB layout and RFI. I am still trying to decide between a traditional PCM with sawtooth generator variety and a self oscillating topology. This will in part be determined by the answers to these questions.
What can I use as a sawtooth generator? I have read on these forums that the old dual opamp circuit is not precise enough. Do I need to use a proper waveform generator IC such as for example the MAX038? I'd rather not...
I would like to use a dual (+/-) supply and I was hoping to use some cheap mosfet driver ICs to drive the FET gates. It is simple enough to run these using a floating supply, but I am unclear on how to implement a level shift or isolation to drive them from a signal which is referenced to ground. It's a shame optocouplers are probably too slow as that would work nicely!
Alternatively I could use one of those fancy bootstrapped high/low side drivers, but again these are made for single supplies and I am unsure how to level shift/isolate the drive signals.
Any advice you can provide on these subjects would be much appreciated!
Many thanks!
Greg.
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hi everyone I'm new and I'm a Technician, need some urgent advice about a starsound 15000d digital Amp. The amp was given to me someone fried the power supply. I have changed almost all the 64N in the PSU ans the driver transistors. And the safety resistors 22ohm haven't touched on the output stage. Switched the amp it goes on and even plays nothing gets hot but I'm hearing a transformer like sound what could it possibly be. Should I have replaced the 1800uf 200V it's six I think. Please anyone out there that can help
Here is a circuit I designed many years ago.
Uses op-amp triangle generator and has level shifting into ir2110
Click on image twice to get clear text.
Uses op-amp triangle generator and has level shifting into ir2110
Click on image twice to get clear text.
An externally hosted image should be here but it was not working when we last tested it.
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Thanks Nigel, that's exactly what I needed!
Could I please see the rest of the schematic, I'm really interested to see how you implemented the whole circuit.
How did it sound?
Many thanks!
Greg.
Could I please see the rest of the schematic, I'm really interested to see how you implemented the whole circuit.
How did it sound?
Many thanks!
Greg.
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Oh, and one more question if you have the time Nigel.
Did you need to do anything special to use the IR2110 with a split supply? I assume you just treated the -35v rail as though it were ground? I can't find much info on using high and low side drivers with split supplies.
Many thanks for your advice!
Greg.
Did you need to do anything special to use the IR2110 with a split supply? I assume you just treated the -35v rail as though it were ground? I can't find much info on using high and low side drivers with split supplies.
Many thanks for your advice!
Greg.
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