Ricardo,
if you want to use higher current, you cant use a higher value resistor with 4 leds. That' s why they use 4 leds in the last pcb. You can always short the forth led and use 3.
Hi vgeorge, I usually use a lower value resistor to set higher current.
Using four diodes with a higher value resistor is new to me... but I found it:
(3xVf LED)-VgsQ101=VdR101. ICCS=VdR101/R101. Example: 3x2.1V LED and a Q101(201,301) MOSFET
with 4.3V Vgs will create 2V drop across a 10 Ohm R101. ICCS=2V/10R=200mA.
So 4 leds will create a 4V drop over R101... if I use R101=15 I get ICCS = 267mA
Perfect
Using four diodes with a higher value resistor is new to me... but I found it:
(3xVf LED)-VgsQ101=VdR101. ICCS=VdR101/R101. Example: 3x2.1V LED and a Q101(201,301) MOSFET
with 4.3V Vgs will create 2V drop across a 10 Ohm R101. ICCS=2V/10R=200mA.
So 4 leds will create a 4V drop over R101... if I use R101=15 I get ICCS = 267mA
Perfect
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You should do the VGS curves of 9530 by eye because the curve embedded in the calc is for 9610. They are Interchangeable on board, but 9610 is the fastest one for open treble while 9530 being no real dork but not as good is the tougher one for special purposes like delivering 1A and beyond to things like WiFi music centre appliances.
Read http://www.diyaudio.com/forums/power-supplies/192625-sslv1-1-builds-fairytales-203.html#post3274708 for an IRF9530 example and its curves annotated for calculations. By using another ICCS red horizontal line level you can find your own points for 3 or 4 Leds populated.
Hi everybody,
Salas recommended at the njfet thread a SSLV1.1 for the FoldedSimplistic that
should draw 200mA (CCS) at 35Vout.
The BiB-cookbook just has schematic without parts and values.
Question: is there somewhere a BOM and schematic for a BiB/SSLV1.1 that
suits the FoldedSimplistic?
Sorry for being lazy
Greetings ulf
Salas recommended at the njfet thread a SSLV1.1 for the FoldedSimplistic that
should draw 200mA (CCS) at 35Vout.
The BiB-cookbook just has schematic without parts and values.
Question: is there somewhere a BOM and schematic for a BiB/SSLV1.1 that
suits the FoldedSimplistic?
Sorry for being lazy
Greetings ulf
No, it has much discussion and examples and there is an Excel calculator on first post also. Anyway, use example (e) with one led only, jumper the second led position. That will put it in the adequate voltage range to set 35V with the trimmer. Use 15R 3W to 5W for R101, R301 and 4x 1.9V leds for D102 etc. it will set circa 200mA CCS. All other non application specific parts have standard values in the guide's bom.
Attachments
Yes, 10V drop over the 1.1 reg is more than fine. Each folded simplistic channel (1x2SK369 input stage, pdf circuit) will consume ~30mA. The 170mA spare will allow for good B+ output impedance when burning on the Mosfets. In case its too hot for your arrangement and sinks, you can use 130mA CCS. It may lose a bit of subjective quality VS 200mA or 300mA, but still very nice.
