Salas SSLV1.3 UltraBiB shunt regulator

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Yes if arranged with a virtual ground in a batteries like manner along with more sections or other floating power sources. See an examplle of two positives making a positive and a negative. SSLV1.3 Ubib doesn't have sense lines so ignore those you see in the example. Think of +Force 0 Force as the Ubib's +Vout 0V outputs.

Pos PSUs Symmetry.jpg
 
I've just finished building the +ive version of this regulator, set for about 1.2A output at 15V. The intent is to use it to power a Topping DS30 Pro DAC.

I initially tested the regulator with a 15R resistor as a load and it maintained 15V across the resistor with out any problem. However, when powering the DAC the DAC flashes up an Int Err on the screen and doesn't boot. I would assume not enough spare current available for the DAC turn on surge. I'm a little cautious of simply upping the headroom current. I wondered if anyone else had seen this before and had a sensible fix.

Ta.
 
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Most likely your Topping DAC needs more current than 1.2A in its boot phase as you say. There's no fix since this has a current limiter. You either set it as high as needed for boot and it suffers wasted current burn during cruise, or you repurpose it for other gear so to build an on demand linear PSU like the L-Adapter for the DAC. Its a series type with no limiter/bias. A very well received go-to solution PSU for such applications.
Nonetheless some users said the high bias shunt (parallel) V1.3 reg you already built has the subjective edge if you can accept and manage the wasted heat with big sinks. Such an approach may demand a higher current M1 Mosfet in your case. Something like an IRF9630. If you used the original BOM's faster responding FQ3P20 M1 its still good for up to 1.77A at 100C core temperature.
 
Always advise L-adapter source for consumptions higher than 500mA. In my opinion above this there is a lot of excess temperature.

Also, most consumers or loads like DACs that draw above 500mA an L-adapter supply is good enough and very low noise, and much more robust and heat efficient.
 
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Depends mostly on constant current setting to average consumption ratio. If its for a circuit pulling 400mA fairly steadily, then a 500mA limit setting will not create much waste dissipation on M2. Actually no matter the absolute mA setting level, M2 mainly cares about the difference between ccs setting and load pull. Vout level is the other thing differentiating M2's dissipation if for same set/load mA bias between applications.
M1 sees full set current all the time and cares. So we tend to keep Vin-vout moderate.
If its a roller coaster load with a big boot time peak, necessitates to set ample current limit for this worst case demand. Then M2 burns away a lot of unused current when the load is in cruising mode.
 
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diyAudio Chief Moderator
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Better avoid an Ultrabib shunt for this. I see difficulties like high Watt dissipation on M1 because of enough Vin-vout a 3A CCS setting will need to work well.

Prefer my L-Adapter simple series PSU design as its geared better for high current including double bulk capacitors. Has also been reported successful in doing tube heaters.
Read in the L-A's instructions PDF my hints on how to choose transformer spec, capacitors size, and sinking approach.
 
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How much spare current were you running in this test?
Measurement was taken at the positive regulator with 150 mA average load and 200 mA spare current. It was in my DCG3 preamplifier which can pull up to 300 mA on full swing and high load. I can direct drive loudspeakers to the enjoyable listening level directly from DCG3. :D
 
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Thank you for your reply , it's confusion situation - I meant to sent you pm , but unfortunately there's moderation rules on the forum which prevents me to do it . Would be very grateful if you can pm me - as friend of mine is going to build for me korg nutube preamp , ( I have already all parts ) and another friend advice me to get your bib shunt regulator - I didn't pay attention to the version , apologies , but if you can help with the newer version - thats would be great . Thank you again . Best regards . Val