As far as i know, all Detex audio class d are prefilter feedback Delta Sigma or hysteresis based.
Post filter feedback is the one and only way to go in self oscillating class d.
In clocked class d, ur best off with open loop fullbridge as phase shift makes AF feedback more or less useless above around 1kHz anyways.
Post filter feedback is the one and only way to go in self oscillating class d.
In clocked class d, ur best off with open loop fullbridge as phase shift makes AF feedback more or less useless above around 1kHz anyways.
Hi!
Recently I have found a great document from TI on PWM and I had thought about this thread.
It has renewed my interest in playing with Class D designs again and it can be found here,
http://www.ti.com/lit/ug/slau508/slau508.pdf
Another neat little component I have also found is the TimerBlox chips from LT.
These are complete PWM systems on one tiny little chip and run as high as 1Mhz!
I have a few of the LTC6992-2's and I will be giving them a try sometime in the future as well, Here is the data sheet,
http://cds.linear.com/docs/en/datasheet/69921234fc.pdf
Just add your favorite drivers and FET's !!!
jer
Recently I have found a great document from TI on PWM and I had thought about this thread.
It has renewed my interest in playing with Class D designs again and it can be found here,
http://www.ti.com/lit/ug/slau508/slau508.pdf
Another neat little component I have also found is the TimerBlox chips from LT.
These are complete PWM systems on one tiny little chip and run as high as 1Mhz!
I have a few of the LTC6992-2's and I will be giving them a try sometime in the future as well, Here is the data sheet,
http://cds.linear.com/docs/en/datasheet/69921234fc.pdf
Just add your favorite drivers and FET's !!!
jer
D
Deleted member 148505
@PetruV
Build the one made by ejtagle first, many diyers who made it are satisfied with its sound.
If you don't have experience in building class d/ amps, well then DIY might turn more expensive, because of failed amps specially if you use junk parts. Instead of buying assembled working modules from the start.
Build the one made by ejtagle first, many diyers who made it are satisfied with its sound.
If you don't have experience in building class d/ amps, well then DIY might turn more expensive, because of failed amps specially if you use junk parts. Instead of buying assembled working modules from the start.
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This schematic i posted is UcD ie post filter feedback self oscillating, V3 is the audio input.
Power you can scale to your liking by choosing rail voltages and mosfets accordingly.
My current setup has one channel running at just shy of 500kHz and the other channel around 600kHz, rail voltages are currently 2x22VDC and i'm using IRF540 mosfets salvaged from a scapped project, the gate drive is a IR2010 and the comparator a MAX913.
Power you can scale to your liking by choosing rail voltages and mosfets accordingly.
My current setup has one channel running at just shy of 500kHz and the other channel around 600kHz, rail voltages are currently 2x22VDC and i'm using IRF540 mosfets salvaged from a scapped project, the gate drive is a IR2010 and the comparator a MAX913.
I only have a preliminary layout which is already posted in another thread, but as i have some EMI issues to deal with i cant recommend it, quite frankly i shouldent have posted this project what so ever until i had the EMC stuff fixed, tested, passed and behind me.
I also need to drop the noise floor quite a bit assuming it is even possible, im gonna assume -60dB is a level noticable throughout a livingroom considering thats where you'll find 0.1% or was it 1% THD.
I also need to drop the noise floor quite a bit assuming it is even possible, im gonna assume -60dB is a level noticable throughout a livingroom considering thats where you'll find 0.1% or was it 1% THD.