Rough draft, modified SOZ with CCS pull-ups & CPU biasing, need advice.

[Brian Guralnick]

Here’s my first brainstorm. My goal is to achieve around 100 watts with a 750 watt supply. I will be feeding this amp with a 10vrms audio signal from a Balanced Zen Line Stage amp.

I’ve also been told that using CCS pull-ups in the SOZ design lowers the damping factor, in an attempt to compensate for this, I’ve added feedback resistors R3 & R4, however, I still haven’t worked out a good value.

The big question, will I get a good sound out of this design?

[Brian Guralnick]

A high res version:

[Nelson Pass]

I don't see any mechanism for controlling the DC value on the
Drains of the diff pair. The simplest approach would be to load
the outputs with some resistance to ground and then adjust
the values of the current sources to the desired values.

[Brian Guralnick]

OOOPS, I just re-uploaded the hi-res version of the schematic, the low res 1 was in there. HIRES:
http://www.diyaudio.com/forums/attac...&postid=255760

The design uses 2 diferenc CPU modules, though, each module has the same circuitry, the software is a little different.

The goal of "AMP_BIAS_CPU1" is to optimize the Drain bias voltage of Q1 & Q2. It takes in nets "fb_Q1 & fb_Q2 (in green)" which are divided by 10, (hence the 10K res divided by 1K res down by the cpu module connector), fed to the 2 x 24 bit AD converters. The module will measure the inputs between (v_neg) and (vn+24), which is 24v regulated above the (v_neg).
The module has 2 x 18 bit voltage out DACs which also go between (v_neg) and +24v.

The goal of the "AMP_BIAS_CPU2" is to maintain the CCS1 & CCS2. It operates between (v_pos) and -24v, (v_pos) regulated down with a negative 24v regulator. It will be trying to maintain a 23v level (from the modules point of view) at the (fb_CC1) and (fb_CC2).

The 2 modules working together can startup the amp nice and slow controled manner, + compensate for warm and general temparature drift, + with internal flash memory, they can chart the potential deteriation of a lemmon part.

[Nelson Pass]

You don't by any chance have one of those hats with a
propeller on it, do you?

[Brian Guralnick]

Originally posted by Nelson Pass
You don't by any chance have one of those hats with a
propeller on it, do you?

LOL, , LOL.... hehehehehehehehe…. Can’t stop laughing.

I just love designing in electronics. The more difficult the design, the more effort I'll put into it. Pressure, big challenges & proving others wrong also helps.

EG: Thing I’ve done in the last 12 months…

Designed 16 PCBs, 10 already came in, designed a real-time graphics DSP core which drives the first 9, 3 additional microcontroller IP cores, all in Verilog, all fully functional, an entire a-la-carte universal digital video format converter / scaler / video tiller / de-interlace / scan converter / genlock / TBC, it’s software, which runs on the 4 previously mentioned IP cores, 2 new provisional patent submittals to add to my existing 3 patents, and, another 6 new PCBs for audio integration, & now, this little amp just for additional experience.

Can't stop giggling.

My existing patents:
6532008 – stereoscopic / holographic / Holoscopic™ ghost removal.
6088052 – stereoscopic line muting interface.
6058192 – universal video sync enhancer & weak sync recovery.
My 2 new ones are for scaling video in such a manner, that, the final result is twice as good as anything else out there.

[Brian Guralnick]

The amp is now 2 PCBs, the main pcb and the CCS pcb.

Here is the main. The RP1 & RP2 are optional for manual control & testing stage, they will eventually be removed.

[Brian Guralnick]

The main pcb...

[Brian Guralnick]

The CCS schematic.

[Brian Guralnick]

The CCS PCB.