The simplistic Salas low voltage shunt regulator - Page 163

Bertel · 09:45 AM

Hi Disco,

many thanks for putting the schematic up!

As Salas has mentioned I will try this for as low as 1v2 - let's see how it will 'behave'... ;-)

Best,
Robert

merlin el mago · 16th December 2009, 01:30 PM

Hi Disco,

Is possible to use your schematic for 3.3V & less current for IC digital regs. app.

Thks & best
Merlin El Mago

beetle · 16th December 2009, 01:46 PM

I guess so. Check this: The simplistic Salas low voltage shunt regulator

Salas · 16th December 2009, 02:03 PM

No beetle, that one will not go lower than 4V, will hit on Mosfet's Vgs limit. Disco's will do 3.3V. For current setting I gave the Ohm's law Vbe/R1. For over 2.8V just use 1K trimmer, and don't go higher than 4V with 9V input because the Mosfet above needs breathing space for its Vgs and some input ripple peak to peak.

Salas · 17th December 2009, 02:53 PM

Quote:

Originally Posted by HiFiNutNut

Salas and others,

I have just come back from my overseas holiday and am ready to be back to DIY again.

What diodes subjectively sound best for rectification?

I am currently using 1N5822 low drop power schottky rectifier 3A.

The higher current rating is necessary for peace of mind - I sometimes use over 100,000uF low ESR for smoothing so the turn-on "short-circuit" current may be huge. I guess the regulators I will build will draw up to 1A constant current.

I can use diodes about or under 40V.

Regards,
Bill

Try the Fairchild Stealth series. There are 2 diodes in one TO-220 package on top of being good. Reverse voltage rating is very high.

HiFiNutNut · 17th December 2009, 11:06 PM

Salas,

Great! I can't be happier with your recommendation!

Those are 600V 30A fast/soft recovery diodes that can be used in power amps! I have been using the cheapiest ordinary diodes in my power amps as I did not know of any high power fast/soft recovery diodes.

Do they give a very noticeable improvement to the power amp? I hope so. Has any one got any experience?

For the CCS/Shunt reg, the voltage and current I will be using won't be more than 24V @1A. Would the much higher rating 600V / 4A diodes work well?

Also, the datasheet suggests that no snubber MAY BE needed. Would a 0.01uF still help?

Regards,
Bill

Salas · 18th December 2009, 08:51 AM

They will work well in lower voltages. For snubbing I don't know.

qusp · 5th January 2010, 03:46 PM

Hi salas, i'm looking to use discos version of your reg for 1.2V supplies for a sabredac build (ESS9012 ackodac) i'm sorted for all but the 1.2v supplies. in fact acko has some 1.2v discrete regs lined up too, but since these are so cheap to build and I can always find a use for a good reg, I thought I would build some of yours up, compare and use the winner (lowest noise) for this dac and the other for a gift or something as I have a few samples of Ti dac chips and some opamps just waiting for an excuse

1.2V +/- 5% (std digital grade). ~50mA

1.2V +/- 5% (analog low noise). ~15mA
Supplies power to analog output ref of dac

do you think the SLVS is suitable? has anyone actually built up the 1.2V version mentioned on the previous page? for lowest noise I would obviosly go for as good matching and best tolerances on the R's and caps, then replace the pot with a set value once I find it. anythimng else you can recommend or things to look out for if i'm going to pioneer ?

. also where do I get PCBs? are there any available at the moment?

Salas · 5th January 2010, 04:14 PM

This is fresh. Only Disco has made one for a very different purpose. That PCB he designed/fabricated himself. I suggest you wire one point to point and test. Maybe its a failure at 1.2V. The parts are so few you can experiment on a perfboard following his layout from his pictures of pcb and build I guess. Only choose a suitable R1 following the simple formula I gave, for about 200mA constant current in your case. He is using 1.2-1.3A at the moment, its on a #26 DHT valve heater/cathode as you know.

jkeny · 5th January 2010, 04:23 PM

Hey, qusp, I was thinking along the same lines myself - building a 1.2V reg ala Disco - this will also do 3.3V, I believe so if proven successful & low noise it would make a nice series of regs for Acko's ESS baord.

I will be getting the D45H8 parts for this soon in my local Radionics - I presume the IRF9540 can be substituted with the P channel IRFP9240?

16th December 2009, 09:30 AM	#1621
Bertel diyAudio Member Join Date: May 2009	Disco/Salas 1v5 shunt reg Hi Disco, many thanks for putting the schematic up! As Salas has mentioned I will try this for as low as 1v2 - let's see how it will 'behave'... ;-) Best, Robert Last edited by Bertel; 16th December 2009 at 09:45 AM.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

16th December 2009, 01:30 PM	#1622
merlin el mago diyAudio Member Join Date: Sep 2009 Location: Blanes - Costa Brava	Hi Disco, Is possible to use your schematic for 3.3V & less current for IC digital regs. app. Thks & best Merlin El Mago

16th December 2009, 01:46 PM	#1623
beetle diyAudio Member Join Date: Mar 2008	I guess so. Check this: The simplistic Salas low voltage shunt regulator

16th December 2009, 02:03 PM	#1624
Salas diyAudio Chief Moderator Join Date: Oct 2002 Location: Athens-Greece	No beetle, that one will not go lower than 4V, will hit on Mosfet's Vgs limit. Disco's will do 3.3V. For current setting I gave the Ohm's law Vbe/R1. For over 2.8V just use 1K trimmer, and don't go higher than 4V with 9V input because the Mosfet above needs breathing space for its Vgs and some input ripple peak to peak.

17th December 2009, 11:06 PM	#1626
HiFiNutNut diyAudio Member Join Date: May 2004 Location: Sydney	Salas, Great! I can't be happier with your recommendation! Those are 600V 30A fast/soft recovery diodes that can be used in power amps! I have been using the cheapiest ordinary diodes in my power amps as I did not know of any high power fast/soft recovery diodes. Do they give a very noticeable improvement to the power amp? I hope so. Has any one got any experience? For the CCS/Shunt reg, the voltage and current I will be using won't be more than 24V @1A. Would the much higher rating 600V / 4A diodes work well? Also, the datasheet suggests that no snubber MAY BE needed. Would a 0.01uF still help? Regards, Bill

18th December 2009, 08:51 AM	#1627
Salas diyAudio Chief Moderator Join Date: Oct 2002 Location: Athens-Greece	They will work well in lower voltages. For snubbing I don't know.

5th January 2010, 03:46 PM	#1628
qusp Sometimes a square peg fits a round hole just fine diyAudio Member Join Date: Oct 2009 Location: Brisbane, Australia	Hi salas, i'm looking to use discos version of your reg for 1.2V supplies for a sabredac build (ESS9012 ackodac) i'm sorted for all but the 1.2v supplies. in fact acko has some 1.2v discrete regs lined up too, but since these are so cheap to build and I can always find a use for a good reg, I thought I would build some of yours up, compare and use the winner (lowest noise) for this dac and the other for a gift or something as I have a few samples of Ti dac chips and some opamps just waiting for an excuse 1.2V +/- 5% (std digital grade). ~50mA 1.2V +/- 5% (analog low noise). ~15mA Supplies power to analog output ref of dac do you think the SLVS is suitable? has anyone actually built up the 1.2V version mentioned on the previous page? for lowest noise I would obviosly go for as good matching and best tolerances on the R's and caps, then replace the pot with a set value once I find it. anythimng else you can recommend or things to look out for if i'm going to pioneer ? . also where do I get PCBs? are there any available at the moment?

5th January 2010, 04:14 PM	#1629
Salas diyAudio Chief Moderator Join Date: Oct 2002 Location: Athens-Greece	This is fresh. Only Disco has made one for a very different purpose. That PCB he designed/fabricated himself. I suggest you wire one point to point and test. Maybe its a failure at 1.2V. The parts are so few you can experiment on a perfboard following his layout from his pictures of pcb and build I guess. Only choose a suitable R1 following the simple formula I gave, for about 200mA constant current in your case. He is using 1.2-1.3A at the moment, its on a #26 DHT valve heater/cathode as you know.

5th January 2010, 04:23 PM	#1630
jkeny Banned Join Date: Feb 2007 Location: Dublin	Hey, qusp, I was thinking along the same lines myself - building a 1.2V reg ala Disco - this will also do 3.3V, I believe so if proven successful & low noise it would make a nice series of regs for Acko's ESS baord. I will be getting the D45H8 parts for this soon in my local Radionics - I presume the IRF9540 can be substituted with the P channel IRFP9240?

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)