Iraudio1

[jake83]

I have been thinking of building slightly modified version of iraudio1 amp.

Amp has adjustable Fsw (R26). What is the lowest freq you can set this amp to work?

I'm intrested Fsw around 80-120 kHz...

This is what I have been thinking of:

- Half bridge topology
- Audio -> PWM (very similiar to IRAUDIO1)
- IR2110 gate driver
- BJT buffered HO and LO
- 12 x IRF640 output devices (6 per side)
- +-70V rail voltages
- No bootstrap, all voltages required are generated in PS (+70V, +5V, 0, -5V, -58V, -70V and one floating 12V for hi side)
- Feedback similiar to IRAUDIO1

I'm will put schematics here soon as there is something to show.

[mitch90]

One floating 12V for hi side might be open invitation for increased EMI/RFI.

Just my two cents.


MITCH.

[jake83]

So bootsrap would be a better choice?

PS and AMP would be constructed in the same circuitboard.

What about switching freq on IRAUDIO1, can it used around 100 kHz?

[mitch90]

Hello.


So bootsrap would be a better choice?
From my perspective that would be better choice.

PS and AMP would be constructed in the same circuitboard.
Linear PS or SMPS?

What about switching freq on IRAUDIO1, can it used around 100 kHz?
Yes, but not as true full range amp.

Regards,


MITCH.

[jake83]

Oh yes, I forgot to mention. This amp is supposed to be for subwoofers use only. This is the fist amp that i'm building and I think low Fsw will make it a little easier to do (no SMD components, low losses, easier to succeed in PCB design, etc.).

Yes, amps at this power levels around (1 kw) aren't good for beginners, but this kind of amp intrests me and I'm also willing accept that this will end in failure. Though I preffer it to work

PS is SMPS, and this is going to car amp, since I have need for one at this time.

I'm also considering clocked amp now.