10.6V-10.9V maybe you gonna end up with, or more if you are not using 5 to 6mA during matching, but really, no problem. Seems that 1.8Vf isn't an easy average to get from generic leds anymore.
OK. 5V you dial and ready to go for LSPD volume control. They must be a killer pair with DCB1. Waiting for your evaluation, bcs I want to try LSPD too when I wil make a new DCB1 on the GB boards, in the future. With so many leds if you add up the 6 extra of the LSPD baby shunt I guess that it asks for a smoked glass enclosure.
If the CCS row of 3 leds is too healthy and the CCS Mosfet comes from a lower Vgs batch then it can pass more steady current than average. If you feel that you got rather hot CCS Mosfets, the ones to the right near the main filter caps, you may screw 'em down to chassis a la Tea-Bag's mounting under pcb, or employ mini heatsinks for all Mosfets and the 7812.
The LED from the BOM has also an Vf Typical of 2V, as seen in the Datasheet.
When searching now on Mouser for LED's with a typical Vf of around 1.8V (yellow) one has to look in the datasheets to know an estimate.
For instance 630-HLMP-1719 has an typical Vf of 1.8V at 2mA
Also 593-VAOL-3HCE4 has a typical Vf of 1.8v at 20mA
Matching/testing then could give better Vf results with these LED's.
Yes, those look closer to the ones I use.
P.S. Enough times the google sheet for the GB sign up asks me for a gmail account log in, other times not. Do you people get the same? Given the initial huge response to the first wiki sign up, is it a bit obscure or locked for some browsers? Does the same in FFOX and Chrome. I will post the url in the original DCB1 thread too.
P.S. Enough times the google sheet for the GB sign up asks me for a gmail account log in, other times not. Do you people get the same? Given the initial huge response to the first wiki sign up, is it a bit obscure or locked for some browsers? Does the same in FFOX and Chrome. I will post the url in the original DCB1 thread too.
I am trying to keep this price, and it looks do-able.
I have gotten qoutes from PCB fab house for larger quantity.
If we go above #100 boards each, then a DIYaudio donation will be increased.
As stated above, things could change.
I see that the list is picking up. I want to thank Tea-Bag, the GB administrator for his effort of making the DCB1S a reality for everyone. And also personally. He did not let me buy the 3 boards I wanted to have, he put my boards on his expense, he refused me to even pay the postage. A very cool guy.
I see that the list is picking up. I want to thank Tea-Bag, the GB administrator for his effort of making the DCB1S a reality for everyone. And also personally. He did not let me buy the 3 boards I wanted to have, he put my boards on his expense, he refused me to even pay the postage. A very cool guy.
Salas,
For all you have done, I think this is the least we as group could do. Additionally, I thank everyone that has contributed to this effort. I do not have the skills to do this on my own, so I really appreciate being allowed to participate in the group buy.
Bill
Yes
Tea Bag is doing GB very objectively and I am sure it will be a great success. Thanks to his effort this had been resurrected from dead.
Now WIki is up on this site - so we can transfer the list here.
Somebody who had done this on Wiki earlier can set it up?
kannan
Sala,
I want to ask a question on the mini shunt regulator, yes, mine one is your design
I need to set the CCS 317 resistor less than 22R to range 5vdc, and 317 (actually is LT1085)become hot and need a heatsink too, remember you mention that they don't need heatsink, while I set it 22R, they just can get 4.2vdc, I just worry about I have got a wrong way?
I think the reason is those matching function 1K trimpot? and so, what is the maximum value can feed to LSPD?
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FingerX,
If you read back a bit you will find BillyK had a similar problem. I would suggest that first you should check the Vf of your LEDs to make sure they match correctly. I think Salas specifies they should have Vf of 1.8V. Higher than that and the output voltage goes below 5V which is to small for Lightspeed as the Lightspeed has 4 voltage greedy LEDs inside the LDRs.
Uriah
If you read back a bit you will find BillyK had a similar problem. I would suggest that first you should check the Vf of your LEDs to make sure they match correctly. I think Salas specifies they should have Vf of 1.8V. Higher than that and the output voltage goes below 5V which is to small for Lightspeed as the Lightspeed has 4 voltage greedy LEDs inside the LDRs.
Uriah
Uriah,
Thanks for your quick reply
the yellow LED Vf is 1.8v to 2.5v, they can go to 5v for 2 in series as their maximum rating, my techer said LED is current source component that they actually not work in one Vf? I just increase the CCS current and they go to 5v, is that any problem if the CCS resistor is less than 22R, which is too much current to feed to the LSPD? or just not over 5v is OK? My current setting is 4.98v
True, as you change current to LED the voltage drop changes. We would like to start with 5V. 4.98 really is nice and I wouldnt worry at that point. When you use the 100R resistors in front of the LDR then the current is not a worry and especially when you have a pot inbetween as well.
More Lightspeed questions should probably be in Lightspeed thread or power supply over in Salas power supply thread. All over the place
Uriah
More Lightspeed questions should probably be in Lightspeed thread or power supply over in Salas power supply thread. All over the place
Uriah
Sala,
I want to ask a question on the mini shunt regulator, yes, mine one is your design
Depends on the Leds. If they have enough Vf and 22R is enough then the 317 will stay cool enough. With your Leds you needed more current, so the heat on the IC got naturally up. Use a little sink in this case.
So, I finished building my Mesmerize board up last night. Everything went well. I have not put power to is yet as I finished up real late and want a set of fresh eyes to look everything over before I power it up.
Nitpicking comments about assembly... The holes for the 1/2 watt resistors were a bit small. The leads did go in, but they were a real PIA. LED orientation would be really nice to have marked on the board. About wiring the input selector switch. I haven't done that yet, and it is not clear how it should be done. It would be great to label + and - and input #
Otherwise it was a smooth build with no real significant issues. Nice work.
Nitpicking comments about assembly... The holes for the 1/2 watt resistors were a bit small. The leads did go in, but they were a real PIA. LED orientation would be really nice to have marked on the board. About wiring the input selector switch. I haven't done that yet, and it is not clear how it should be done. It would be great to label + and - and input #
Otherwise it was a smooth build with no real significant issues. Nice work.
What is your leds Vf at 5-10 mA current, doing the 9V battery test match? Around 2V? With your final current, 30mA per string when LSPD draws near zero, you will be still OK. If the leds don't have 2.5Vf at 5-10mA, then will have it at 20-30, if you want it to work with a 22-27R the leds must be different. Having current reserve aint bad, even if you need a little sink on the IC in the end.