Reflektor-D builds

[stefan646]

Rds on is not relevant in this circuit because its not a switcher

From my knowledge, if a MOS has a lower Rds on, then the power that it dissipate is lower and because of that the MOS isn't heating that much.
Because I plan to do the 8V version, I want to reduce heat. + they are cheaper too, but this is not the main cause of course

 

[Salas]

Here both are constantly biased so their dissipation will be Vds x Ib

 

[stefan646]

Here both are constantly biased so their dissipation will be Vds x Ib

Oh...I understand, stupid me

So there is no way that I can reduce heat by using a different/powerful MOSFET?

EDIT: maybe a better junction to case/ambient temperature?

 

[Salas]

Yes but they will be somewhat slower devices due to the more robust tend to usually have higher Ciss Crss etc

 

[stefan646]

Yes but they will be somewhat slower devices due to the more robust tend to usually have higher Ciss Crss etc

I understand. So a solution will be to find a similar characteristic MOSFET, but with lower junction to case temperature Sorry for beeing so fixed on this subject, but MTP3055VL is obsolete, and I can't find it locally

 

[Salas]

You don't need low Vgs (th) TTL type like it since you won't use it for below 5.5V Vout. See to get a robust PMOS that you like with comparably low Crss & low RθjC or better.

 

[stefan646]

You don't need low Vgs (th) TTL type like it since you won't use it for below 5.5V Vout. See to get a robust PMOS that you like with comparably low Crss & low RθjC or better.

Very helpful information, thank you ! One last question before I start my search: how much should be the minimum Vdss and drain current? I am planning to run on 0.3A CSS and I have a 12Vac transformer.

 

[Salas]

Let it 100mA spare Id at least to keep it happy. Spare = what the load max will be leaving out unused from the main CCS mA. Don't let Vdss be lower than +25% Vgs (th). Vdss = Vout in this circuit.

 

[samoloko]

using Reflektor D to supply analogue

It Is mentioned that Vref filtering electrolytic 1000 uF has Impact to sound quality
Is 1000 uF value recommended when we power digital loads
what type and value for Vref filt cap would you recommend If we use reflektor D to power analogue

 

[TioFrancotirador]

It Is mentioned that Vref filtering electrolytic 1000 uF has Impact to sound quality
Is 1000 uF value recommended when we power digital loads
what type and value for Vref filt cap would you recommend If we use reflektor D to power analogue

See my post. Hopefully it will help you:
http://www.diyaudio.com/forums/power-supplies/261031-reflektor-d-builds-77.html#post4800117

 

[sbelyo]

I'm finally building one of my reflektor kits for my BIII. What was the resistor numbers, values, and LED combo to get 5.25 V out?

I tried searching but didn't see what I needed.

 

[Salas]

The pdf manual says exactly how to do it. Don't rely on prefab values from others builds since your Vref components tolerances may vary.

 

[sbelyo]

Good point... I'll re-read the manual tonight

 

[sbelyo]

Ok, it looks like two green LED's and a resistor for the Rx part. How do I calculate the value of the resistor for Rx? What wattage should it be?

 

[clsidxxl]

Ok, it looks like two green LED's and a resistor for the Rx part. How do I calculate the value of the resistor for Rx? What wattage should it be?

0.02V pour 10 Ohm, 0,2 V pour 100 Ohm etc,1\4 Watt is ok

 

[sbelyo]

Thanks... Actually I found my first posts from merlin's build so I'll start with the two green LED's and test fit them then calculate Rx (most likely will be 100R)

 

[TioFrancotirador]

Thanks... Actually I found my first posts from merlin's build so I'll start with the two green LED's and test fit them then calculate Rx (most likely will be 100R)

If you do JFET mod (which is must mod for me) then with just two green LEDs (no resistor) you will have around 5,25V.
Here is the link for JFET mode:
http://www.diyaudio.com/forums/power-supplies/261031-reflektor-d-builds-16.html#post4061919

 

[wyan]

Hi, Salas,

What is the component under the green led in this photo? (in orange square) Would love to buy some since it helps rolling the parts. Thanks.


WYAN

 

[Salas]

Socket pins. 0.1 inch pitch SIP cut from a row. Like such 30-PIN HI-REL SIP SOCKET, 0.1"CTRS SNAPPABLE | All Electronics Corp.

 

[samoloko]

See my post. Hopefully it will help you:
http://www.diyaudio.com/forums/power-supplies/261031-reflektor-d-builds-77.html#post4800117

thank you for reply

I ve read It but It Is meant for digital
can we lower C2 value to 470 uF If we use to supply analogue loads