Building a symmetrical psu B1 buffer - Page 160

Tea-Bag · 26th June 2010, 01:41 PM

It sure will. You can use 3v LED's instead.

Mouser pn MV5352

The typical red is 1.8v x 5 = 9v

I am not sure if they will be too noisy. Other's may comment on that. I know 12v one's Salas told me are risky.

chchyong89 · 26th June 2010, 02:09 PM

out of curiousity on 15vdc with salas's shunt reg, possible? anyone can guide me in this? if possible with some calculation too, so that i can learn from you guys

massimo · 26th June 2010, 02:59 PM

there're several designs up to 60V out and even HV schems up to 300V out for tube freaks.
The simplistic Salas low voltage shunt regulator
Simplistic Mosfet HV Shunt Regs

ClaveFremen · 26th June 2010, 06:28 PM

Hello,

I'm in trouble with LED matching...

I must have missed something.

I've bought LEDs in v4.3 BOM (Mouser 593-VAOL-3HCE4), and measured forward voltage of each LED fed by a 9V battery and a 1K2 resistor in series (right, isn't it?).

Measures varies from 1,901V to 1,910V, in spec according to datasheet (mav 2V froward voltage) but far from the typical 1,8V expected value.

So no way of getting 9V or 5,4V (9,53V and 5,70 are best match)

Help!

Salas · 26th June 2010, 06:37 PM

It will be OK. The Vout values will still track with positive somewhat higher as expected and in sweet spot range. Just find 2 similar strings.

regiregi22 · 26th June 2010, 06:38 PM

I had the same results when matching my leds (same part number). You will get a few more tens of a volt in the supply rails. Nothing to worry about.
Other people in the thread reported to have the same values with the same part number.

Regards,
Regi

AndrewT · 26th June 2010, 06:52 PM

I have red LED from different suppliers that vary between 1.55V and 1.95V.

ClaveFremen · 26th June 2010, 07:09 PM

Quote:

Originally Posted by Salas

It will be OK. The Vout values will still track with positive somewhat higher as expected and in sweet spot range. Just find 2 similar strings.

Quote:

Originally Posted by regiregi22

I had the same results when matching my leds (same part number). You will get a few more tens of a volt in the supply rails. Nothing to worry about.
Other people in the thread reported to have the same values with the same part number.

Thanks everyone, so it's OK

Powered ON soldering iron again...

Quote:

Originally Posted by AndrewT

I have red LED from different suppliers that vary between 1.55V and 1.95V.

Wow! So I suppose I've been lucky...

Tea-Bag · 26th June 2010, 07:20 PM

Like mentioned before, it's more important to have two strings have similiar total values than the trying to get lower one's. I am using the yellow one's, and they sit @ 10v.

ClaveFremen · 26th June 2010, 09:26 PM

Well, soldering iron now is powered OFF...

Haargh, my R-Core transformer is still shipping from France...

I've implemented directly last mods, I think...

Vref caps are Wima MKS2XL 2,2uF, the value is ok?

Is 10 Ohm 5W the right value to replace the 68 Ohm couple?

Thanks in advance

26th June 2010, 01:41 PM	#1591
Tea-Bag not politcally affiliated diyAudio Member Join Date: Feb 2006 Location: Kennebunk Blog Entries: 7	It sure will. You can use 3v LED's instead. Mouser pn MV5352 The typical red is 1.8v x 5 = 9v I am not sure if they will be too noisy. Other's may comment on that. I know 12v one's Salas told me are risky. __________________ Salas Boards 2013 #2 CLICK HERE \| F6 Covertible PCB GB Boards Available \|DCB1 boards and KITS available PM\|SemiSouth R125, R100, R100A Available CLICK HERE \|F5TC Boards Sign UP CLICK HERE

26th June 2010, 02:09 PM	#1592
chchyong89 diyAudio Member Join Date: Apr 2009	out of curiousity on 15vdc with salas's shunt reg, possible? anyone can guide me in this? if possible with some calculation too, so that i can learn from you guys __________________ ~.~

26th June 2010, 06:28 PM	#1594
ClaveFremen Reality first! diyAudio Member Join Date: May 2005 Location: Milan, Italy	Hello, I'm in trouble with LED matching... I must have missed something. I've bought LEDs in v4.3 BOM (Mouser 593-VAOL-3HCE4), and measured forward voltage of each LED fed by a 9V battery and a 1K2 resistor in series (right, isn't it?). Measures varies from 1,901V to 1,910V, in spec according to datasheet (mav 2V froward voltage) but far from the typical 1,8V expected value. So no way of getting 9V or 5,4V (9,53V and 5,70 are best match) Help! __________________ Dario ClaveFremen "Bailando Salsa en el Sietch" - My_Ref Fremen Edition GB Second Run

26th June 2010, 06:38 PM	#1596
regiregi22 diyAudio Member Join Date: May 2009 Location: Madrid (Spain)	I had the same results when matching my leds (same part number). You will get a few more tens of a volt in the supply rails. Nothing to worry about. Other people in the thread reported to have the same values with the same part number. Regards, Regi __________________ diyAudio, doing it as big as you can, JUST BECAUSE WE CAN!

26th June 2010, 07:20 PM	#1599
Tea-Bag not politcally affiliated diyAudio Member Join Date: Feb 2006 Location: Kennebunk Blog Entries: 7	Like mentioned before, it's more important to have two strings have similiar total values than the trying to get lower one's. I am using the yellow one's, and they sit @ 10v. __________________ Salas Boards 2013 #2 CLICK HERE \| F6 Covertible PCB GB Boards Available \|DCB1 boards and KITS available PM\|SemiSouth R125, R100, R100A Available CLICK HERE \|F5TC Boards Sign UP CLICK HERE


	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

26th June 2010, 02:59 PM	#1593
massimo diyAudio Member Join Date: Dec 2002 Location: Milan, Italy	there're several designs up to 60V out and even HV schems up to 300V out for tube freaks. The simplistic Salas low voltage shunt regulator Simplistic Mosfet HV Shunt Regs

26th June 2010, 06:37 PM	#1595
Salas diyAudio Chief Moderator Join Date: Oct 2002 Location: Athens-Greece	It will be OK. The Vout values will still track with positive somewhat higher as expected and in sweet spot range. Just find 2 similar strings.

26th June 2010, 06:52 PM	#1597
AndrewT diyAudio Member Join Date: Jul 2004 Location: Scottish Borders	I have red LED from different suppliers that vary between 1.55V and 1.95V.

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

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
New-building of my B1 buffer	Babowana	Pass Labs	328	20th February 2010 01:14 AM

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