Some people say that use chip reduce component i.e. no level shifter, comparator, and so on so it is faster.
That is totally wrong!
Class D with N-Fets always has similar part: Comparator, Level Shifter, Inverting, bootstrap, Low and High Driver and finally the mosfet. In chip it is packed. You cannot tweak. With discrete, there are many circuit possibility designer can take, from as simple as possible untuk complicated, cascode and so on.
The key is how fast which sometime new parts are faster.
And the faster is the key.
That is totally wrong!
Class D with N-Fets always has similar part: Comparator, Level Shifter, Inverting, bootstrap, Low and High Driver and finally the mosfet. In chip it is packed. You cannot tweak. With discrete, there are many circuit possibility designer can take, from as simple as possible untuk complicated, cascode and so on.
The key is how fast which sometime new parts are faster.
And the faster is the key.
You're not quite right)))
The delay in the comparator and driver stages has a very strong effect. The lower they are- Higher loop gain- the better the sound. Even with silicon transistors.
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Selling price is also concern.
And profit as the most. The designer said fast switching is not the only. Class D no need at 1MHz level. 400kHz fsw is just right. So that overall delay can be covered using ordinary parts.
Sure it is good if you make this only several unit for your self. Or your customer is so premium.
But selling OEM at 100USD per pc is not the case.
And profit as the most. The designer said fast switching is not the only. Class D no need at 1MHz level. 400kHz fsw is just right. So that overall delay can be covered using ordinary parts.
Sure it is good if you make this only several unit for your self. Or your customer is so premium.
But selling OEM at 100USD per pc is not the case.
Switching at appx 400kHz typically is good enough for hifi.
For pro audio usually 250kHz for big amp, 275 to 300kHz for smaller. Some PA amplifier are designed as hi fi size, 200W to 400W which adopt similar circuitry as hifi.
GaN offer fast, less losses and so smaller footprint. Easy manage dead time
For pro audio usually 250kHz for big amp, 275 to 300kHz for smaller. Some PA amplifier are designed as hi fi size, 200W to 400W which adopt similar circuitry as hifi.
GaN offer fast, less losses and so smaller footprint. Easy manage dead time
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These are two different things. GaN allows for shorter dead times, which helps reduce distortion. You can still have a feedback loop which will then be more effective since it has less distortion to correct. Of course the fact that ucd comparator delay is long limits the bandwidth, but 100ns translates to, what? 10mhz? That would not be the biggest problem I think.