I just wanted to bring a neat new gate driver to your attention.
IRS20124S Announcment
It's got a built in dead time generator.
IRS20124S Announcment
It's got a built in dead time generator.
This looks like a very good MOSFET driver for Class D applications.
It has over-current protection, 4 discrete adjustable deadtime levels, one input to drive both MOSFET's, low propagation delay, +/-1A drive voltage, suited for ~200V environments and shoutdown.
The only thing I could have thought of was an integrated input level shifter for split supply operation.
Let's see what the price and accessibility will be.
It has over-current protection, 4 discrete adjustable deadtime levels, one input to drive both MOSFET's, low propagation delay, +/-1A drive voltage, suited for ~200V environments and shoutdown.
The only thing I could have thought of was an integrated input level shifter for split supply operation.
Let's see what the price and accessibility will be.
I don't know, IVX, it is a little stange but it makes it very simple to employ shoot through protection without putting the amp in shutdown.
Integrate, or count, the OC error pulses, on the first pulse the dead time is increased from 15ns to 30ns, next OC it is increased to 45ns, and only then after the dead time is on maximum does the amp shutdown.
Integrate, or count, the OC error pulses, on the first pulse the dead time is increased from 15ns to 30ns, next OC it is increased to 45ns, and only then after the dead time is on maximum does the amp shutdown.
IVX said:Nice chip, but why SD implemented so strange, they have not more silicon area for only ONE 10mA mosfet?
I'd like to see them use those three NC more constructively and use them as ground planes/ shields between the HO and LO pins which I think should at least be on the same side of the chip!! Have fun making a good PCB for this one. How strange is that?
Might help Mueta and Tripath out too, but I'm sure they must have thought of that themselves yeah? It's just the IDE cable, 40 wire versus 80 wire, where the extra 40 are grounds and it doubles the bandwidth.
So, I love the matched delays, and the slower rise time than fall time.
I don't think I'm a fan of the 4 dead time settings, do you think it can be so simple? Could be tricky to use this thing right.
Thanks for posting about it.
Regards,
Chris
Yes, the variance in dead time is a bit scary. It's unfortunate that a great component- and space-saving feature like dead time control in the gate driver seems to be bungled.
Another frighteneing thing about the chip is that the OC protection shouldn't work correctly with a half bridge. In a full bridge, a lower device would always be conducting on one side of the bridge. A half bridge would only allow a proper OC protection half the time and some lesser form of OC protection when the lower device is off. When the blocking diode of the lower device is on a voltage would be present to sense but I'm not totally convinced the OC protection works as advertised bi-drectionally. Maybe I'm missing something.
A propogation delay of 70ns also isn't very good when other drivers have half that.
Overall, at the lower power levels the IRS20124 should be used at it would seem to show promise.
Another frighteneing thing about the chip is that the OC protection shouldn't work correctly with a half bridge. In a full bridge, a lower device would always be conducting on one side of the bridge. A half bridge would only allow a proper OC protection half the time and some lesser form of OC protection when the lower device is off. When the blocking diode of the lower device is on a voltage would be present to sense but I'm not totally convinced the OC protection works as advertised bi-drectionally. Maybe I'm missing something.
A propogation delay of 70ns also isn't very good when other drivers have half that.
Overall, at the lower power levels the IRS20124 should be used at it would seem to show promise.
You could probably make the dead time on this chip work with some very complex external adaptive circuitry. The only difference from doing it with this driver over most others, you'd require even more complex circuitry in order to step the internal dead time settings up or down as required.
If you can get that to work on paper, you probably won't IRL.
Lars, you were alot bolder in your judgment of this chip than I was, but we're thinking along the same lines.
I've seen light dimmers that are more advanced, IR scewed up on this one, but it's nice to know they're thinking about us
Regards,
Chris
If you can get that to work on paper, you probably won't IRL.
Lars, you were alot bolder in your judgment of this chip than I was, but we're thinking along the same lines.
I've seen light dimmers that are more advanced, IR scewed up on this one, but it's nice to know they're thinking about us
Regards,
Chris
Canadian guy who work on class D Amp...
Hi guy I'm Fred from www.d-amp.com. Now company is growing and I'm looking for some other technical guy to design small class d amplifier and switching PSU. For now, a 8Kw 1 Rack space amplifier is in production and we looking forward for multichannel amplifier, some DSP stuff and processing. If you'r close to montreal and interested, let me know! Unfortunately, working environement is french, but most people in shop speak english too. Thank's for your time!
Fred
frederic.bourque@d-amp.com
Hi guy I'm Fred from www.d-amp.com. Now company is growing and I'm looking for some other technical guy to design small class d amplifier and switching PSU. For now, a 8Kw 1 Rack space amplifier is in production and we looking forward for multichannel amplifier, some DSP stuff and processing. If you'r close to montreal and interested, let me know! Unfortunately, working environement is french, but most people in shop speak english too. Thank's for your time!
Fred
frederic.bourque@d-amp.com
Charles, i like the distributed workshop idea, it is often in the programming, modeling etc, why other task type not use so worksharing? DIY domain is surely showed good efficiency of the such approach already (You->Pierre, You->Lars etc.. other->other).
PS: Do we can have the great ideas during fishing, skateboarding, or when we are in the office only?
PS: Do we can have the great ideas during fishing, skateboarding, or when we are in the office only?
Hi,
I dont' think he was asking about distributed workshop type of DIY thing. The problem there is everyone gives their all with the best of intentions (a better circuit for everyone), and one guy runs away with all the money.
Commuting is cool, but not always the answer.
Anyway, I'm "close" to Montreal, and if you've ever seen the women there, you'd move in a second. Oh yeah, you can buy beer at the corner store too, 2$ a liter.
Regards,
Chris
I dont' think he was asking about distributed workshop type of DIY thing. The problem there is everyone gives their all with the best of intentions (a better circuit for everyone), and one guy runs away with all the money.
Commuting is cool, but not always the answer.
Anyway, I'm "close" to Montreal, and if you've ever seen the women there, you'd move in a second. Oh yeah, you can buy beer at the corner store too, 2$ a liter.
Regards,
Chris
Picture of new 8000W Class d amplifier
Hello guy
You can see news picture of my 8000Kw amplifier on my web site (www.d-amp.com). Thank's to all guy who have reply to job offer, I got my guy!
For all other who ask me question about design, most of them was about pumping effect on single ended amplifier...I can give you my trick on my first series, I'm now in 4 quadrant output stage, so no more pumping effect.
The simple way is too add a small switching power supply who return (clamp) the amplifier bus voltage to the bulk capacitor of the main switching power supply. The trick is that if you have a voltage doubler main switching power supply (means 340V), and for example +/- 90V amplifier power supply, you just design a 180V (sum of the +/-90V) to 330V power supply. If amplifier rail go over 186V, the impédance of the main line will ''clamp'' the voltage trought switching. A simple IR2153 with a pair of IRF640 and a TN29/19/7.5 toroidal will do the job.
In that way, you will clamp amplifier rail with very high effiency! And best, return this energy to power supply...Think about this!
Another trick I have use in my model 2000, is to simply add 2 more turn on the output filter (speaker side) with 2 MUR840 diode to clamp to the power supply. This will saturate the coil when speaker feed back their energy to the amp and force amplifier to compensate (if you use analogue feedback instead of ''digital'' feedback!).
So thank's to Dan Blouin to join the D-Amp team!
Have a nice day!
I share some trick, so dont think I'm here to take you idea and the money!
Now, just to know if someone have built amplifier with analogue feedback and have some waveform probleme ( on the scope) over 10Khz....But amplifier pass distortion mesurement...Weird...I work on this now....
Bye
Fred
Hello guy
You can see news picture of my 8000Kw amplifier on my web site (www.d-amp.com). Thank's to all guy who have reply to job offer, I got my guy!
For all other who ask me question about design, most of them was about pumping effect on single ended amplifier...I can give you my trick on my first series, I'm now in 4 quadrant output stage, so no more pumping effect.
The simple way is too add a small switching power supply who return (clamp) the amplifier bus voltage to the bulk capacitor of the main switching power supply. The trick is that if you have a voltage doubler main switching power supply (means 340V), and for example +/- 90V amplifier power supply, you just design a 180V (sum of the +/-90V) to 330V power supply. If amplifier rail go over 186V, the impédance of the main line will ''clamp'' the voltage trought switching. A simple IR2153 with a pair of IRF640 and a TN29/19/7.5 toroidal will do the job.
In that way, you will clamp amplifier rail with very high effiency! And best, return this energy to power supply...Think about this!
Another trick I have use in my model 2000, is to simply add 2 more turn on the output filter (speaker side) with 2 MUR840 diode to clamp to the power supply. This will saturate the coil when speaker feed back their energy to the amp and force amplifier to compensate (if you use analogue feedback instead of ''digital'' feedback!).
So thank's to Dan Blouin to join the D-Amp team!
Have a nice day!
I share some trick, so dont think I'm here to take you idea and the money!
Now, just to know if someone have built amplifier with analogue feedback and have some waveform probleme ( on the scope) over 10Khz....But amplifier pass distortion mesurement...Weird...I work on this now....
Bye
Fred
Hi IVX
You seem impressed by the 0% intermodulation distortion...Just to let you know that analogue feedback provide as much fast tracking of output that intermodulation have no effect in my amplifier, except at full power...you know why! Dont expect this with feedback before the output coil!
Have a nice day!
Fred
You seem impressed by the 0% intermodulation distortion...Just to let you know that analogue feedback provide as much fast tracking of output that intermodulation have no effect in my amplifier, except at full power...you know why! Dont expect this with feedback before the output coil!
Have a nice day!
Fred
One guy runs way with all the money......
Hi Guys,
Chris, I once heard it said that 'it is possible to make a small fortune in the audio business, the trouble is that you have got to start with a large one.....'
On a slightly different note, i heard an open loop D class amplifier the other day, and it was one of the best amplifiers i have ever heard.
The bass was simply astonishing...... so the low inherant damping factor did not seem to have a bearing on bass quality per se.
I realise that matching to the load is a tricky business, but this kind of experience made me question my feelings on post filter feedback.
THD on this amplifier was about 0.1% across the board.....
Cheers
Sheriff
Hi Guys,
Chris, I once heard it said that 'it is possible to make a small fortune in the audio business, the trouble is that you have got to start with a large one.....'
On a slightly different note, i heard an open loop D class amplifier the other day, and it was one of the best amplifiers i have ever heard.
The bass was simply astonishing...... so the low inherant damping factor did not seem to have a bearing on bass quality per se.
I realise that matching to the load is a tricky business, but this kind of experience made me question my feelings on post filter feedback.
THD on this amplifier was about 0.1% across the board.....
Cheers
Sheriff
But it would be fair to say that feedback before the output filter will reduce IMD woudn't it? Simply because you have one less unlinear factor in the feedback ( / mixer ) loop.
Charles i am surprised that you don't already work in making class D amplifiers, because i think of you as one of the great capacities on this area. But i had satisfied myself with the explanation that you were working outside the audio business, where the money is bigger and the sun always shines
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