H-Bridge resources

[thylantyr]

H bridge references.

Eval board.
http://www.diyaudio.com/forums/showthread.php?threadid=15024&highlight=%22h+bridge%22

Schematic for that board above.

wwwlea.upb.de/Aktuelles/Projektseminar/
High_Power_Digital_Audio_Amplifier_mit_Hip4080A_Ev al2.pdf


http://www.chipcenter.com/circuitcellar/december99/c129r20.htm
Harris Corporation has sold most of their Semiconductor line to Intersil, but no matter what you want to call them, they have some of the best tutorial papers on Class-D Audio.

The HIP4080 is a member of the HIP408X family of high-frequency H-Bridge driver ICs. The HIP4080 H-Bridge driver IC provides the ability to operate from 8 VDC to 80 VDC busses for driving Channel MOSFET H-Bridges. The HIP4080, packaged in either 20-lead DIP or 20-lead SOIC, provides peak gate current drive of 2.5 A. A combination of bootstrap and charge-pumping techniques is used to power the circuitry that drives the upper MOSFETs of the H-Bridge. The bootstrap technique supplies the high instantaneous current needed for turning on the power devices while the charge pump provides enough current to maintain bias voltage on the upper driver sections and MOSFETs.

HIP4080 80V/2.5A Peak, High Frequency Full Bridge FET Driver
http://www.intersil.com/data/an/an9324.pdf

HIP4081 80V/2.5A Peak, High Frequency Full Bridge FET Driver
http://www.intersil.com/data/an/an9325.pdf

HIP4080A 80V/2.5A Peak, High Frequency Full Bridge FET Driver
http://www.intersil.com/data/an/an9404.pdf

HIP4081A 80V/2.5A Peak, High Frequency Full Bridge FET Driver
http://www.intersil.com/data/an/an9405.pdf

Links above
http://www.intersil.com/product_tree/
select 'power mosfet drivers', then
click 'full bridge'.

LX1720
http://www.microsemi.com/microcurrents/sum99_pg13-14.pdf


download this document. Pretty /cool
http://www.iweil.com/audio/class_d.pdf

Appears the author wants to build a
multilevel interleaving class d amp.

...asking the folks at diyaudio for more
resources.

[hieroglyphics]

Upon observation of a schematic on this website (http://power.ece.uiuc.edu/Balog/images/Analog%20Pulse%20Width%20Modulation%20Amplifier%20 rev%203-19-03%20public.pdf) (page 11/13) it seems to me that the output of an H-bridge would be a balanced signal as opposed to the common differential ouput. Is this true? I'm still trying to grasp how this works and that is what I interpreted.
Very interesting to say the least! Thanks for the links, thy!

same link as above:
power.ece.uiuc.edu/Balog/images/Analog%20Pulse%20Width%20Modulation%20Amplifier%20 rev%203-19-03%20public.pdf

[thylantyr]

Silly me. The original discussion was
here;

http://www.caraudioforum.com/vbb2/showthread.php?s=&threadid=158522

Since then, I created this thread to focus
on this topic.

H bridge is easier to understand in
terms of motor control. By turning on
two of four transistors you can cause
the motor to turn. By turning off those
two transistors and turning on the
other two transistors, the voltage
across the motor is reversed, the motor
spins the other way. Apply this to
a woofer to cause forward/back motion.

In the standard design, (non H) they ground
one end othe speaker and use a positive voltage to move the speaker
one way, then the signal goes negative
voltage to reverse motion.

positive/negative in respect to it's
ground which is zero.

The link above ain't worky ?

[thylantyr]

Here is something interesting.

Crown BCA.
http://www.crownaudio.com/pdf/amps/bcapaper.pdf

Post #5 explains operation clearly.
http://www.diyaudio.com/forums/showthread.php?threadid=1699&highlight=

Then Zen Master Nelson Pass always
has clever replies to 'new' technology.

Nelson Pass
The one and only
Post #7

The rationale for these alternative circuits is mostly
energy efficiency.

I have built them all, and can say with some authority that
none of them saves all that much energy over plain old
Class AB circuits with stupid linear supplies when used
for music.

If you are running continuous waves into industrial
equipment for long periods of time , it makes sense,
but if you are really serious about saving energy in
an audio system, use speaker drivers with greater
sensitivity.

You can dissipate 1100 watts driving an 80 dB speaker
with a switcher, or you can dissipate 200 watts driving
a 90 dB speaker.


Nelson Pass
The one and only
Post #11

Yawn.

So Crown has invented the bridged switching amp.


Nelson Pass
The one and only

Post #16

Yeah, I got one of those, but it sounds like cra.p unless
you are constantly tweaking your chemical intake.

Nelson Pass
The one and only

Post #30

Alright, I relent:

The Crown circuit is actually clever, but the promotional
bullsh*t is not.

Personally, I agree that one of these days switching amps
will rule the world, and old fogeys like me will be sitting
around pining for the good old analog days. If there's
anything left to sit on.

[southshore]

Originally posted by thylantyr
H bridge references.




IIRC, no current manufacturer uses h-bridge topology in their amplifiers. H-bridge is more expensive due to more discrete parts but has some definite perfomance advantages. Can anyone confirm that?

southshore

[thylantyr]

Originally posted by southshore



IIRC, no current manufacturer uses h-bridge topology in their amplifiers. H-bridge is more expensive due to more discrete parts but has some definite perfomance advantages. Can anyone confirm that?

southshore

On the original thread (see post #3), SPL15 and I were in discussion, his MMATS is H-bridge. He said he's seen others, but
I don't know which ones.

We we talking about dual rail vs. single rail advantages,
the single rail seems to yield 2x advantage, but I
threw out the question on the solid state forum
and I got an answer.

djk is one of the better electronic minds in the internet world
and his response is;

The best I would figure on long term would be an increase in current of 1.414, IOW about 70% of what you could get if you ran the [tranformer] the way it was designed.

This seems to confirm SPL15's experiment. In our example,
for dual rail supplying 50v@10A (500VA), if only one
section is used at a time, the most you can get would be
50v@17A = (850VA) from that section.

This is an unsual electronics question, not many were able
to give an answer //hehe// Normally, one just uses
the rating on the transformer and to yield more current
you would have to parallel the secondaries. But, people
that design with dual rails for power supply normally
expect both rails to be under load, in the case of the
amplifier, only one rail is heavily loaded at time, so
we wondered what the max theoretical current that
can be obtained.

Overall, the single supply would seem more effecient
as you would get 20A, but the dual rail still would yield
17A. I wondered about this because, if single supply
had the 2x advantage, if true, then everyone who designs
class D amplification would use H-bridge, but this is not
the case. Even Crown uses their own interesting topology
that uses dual rail, therefore dual rail is not that inferior.

[southshore]

Originally posted by thylantyr


On the original thread (see post #3), SPL15 and I were in discussion, his MMATS is H-bridge. He said he's seen others, but
I don't know which ones.


I should have said "except MMATS". The engineer who wrote the audio application papers for Harris also designed the MMATS amplifiers.

southshore

[thylantyr]

Jan Didden posted this regardling our transformer scenario;


You have here a hughe safety factor. Unless the amp is used to drive a lamp or something at 1kW constantly, the real output of the amp over time may be no more than 1/10th of that, even with rock music. During the 1kW peaks, it's up to the supply caps to supply the current to the output stage. I mean, the bridge diodes only conduct 10% or so of each mains cycle anyway, so the xformer is effectively disconnected from the amp 90% of the time. Go figure.

Jan Didden

http://www.diyaudio.com/forums/showthread.php?threadid=20883

This is a real world example I suppose, but again people
DO drive tones in car audio - /hehehe