agreed!!
also, btw the stock shunt supplies 4 pins, not 2 there are 2 x AVCC pins (for left and right) at 3v3 and 30ma and 2 x DVCC (also for left and right) at 1v2 and 15ma as i was explaining on the previous page, but in reference to another sabre dac. i have the buffalo 2 as well, not sure if the shunt has 4 on there, or whether it supplies left and right channels in parallel. I think the latter, although there is only 2 leds on there, there does seem to be a transistor for each output
also, btw the stock shunt supplies 4 pins, not 2 there are 2 x AVCC pins (for left and right) at 3v3 and 30ma and 2 x DVCC (also for left and right) at 1v2 and 15ma as i was explaining on the previous page, but in reference to another sabre dac. i have the buffalo 2 as well, not sure if the shunt has 4 on there, or whether it supplies left and right channels in parallel. I think the latter, although there is only 2 leds on there, there does seem to be a transistor for each output
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Being 105C when amongst towering sinks and high current like in your case. Having low impedance @ 100kHz if mentioned in its spec.
Hi Salas
I mounted the board to +15 V. .. right! Works correctly.
I have a problem with the board-15V. The green LEDs (D202, 203.204) is not lit. The resistance mosfet Q206 and R201 will get very hot very very quickly. Q201 remains cold.
Everything seems connected properly.
Where do you start looking? my skills are scarce.
Br
Al
I mounted the board to +15 V. .. right! Works correctly.
I have a problem with the board-15V. The green LEDs (D202, 203.204) is not lit. The resistance mosfet Q206 and R201 will get very hot very very quickly. Q201 remains cold.
Everything seems connected properly.
Where do you start looking? my skills are scarce.
Br
Al
Hi Salas
Indeed, an LED was damaged.
Now works correctly. 1R5 R1 and the voltage is 0.7 V through, but I do not understand. Depending on the dummy load resistance, the voltage varies from 0 to 0.5 V Output and trimmer can reach the target voltage or understatement.
What value of resistance I have to use for testing?. My goals are 5V and 15V.
Indeed, an LED was damaged.
Now works correctly. 1R5 R1 and the voltage is 0.7 V through, but I do not understand. Depending on the dummy load resistance, the voltage varies from 0 to 0.5 V Output and trimmer can reach the target voltage or understatement.
What value of resistance I have to use for testing?. My goals are 5V and 15V.
Hi Salas
Indeed, an LED was damaged.
Now works correctly. 1R5 R1 and the voltage is 0.7 V through, but I do not understand. Depending on the dummy load resistance, the voltage varies from 0 to 0.5 V Output and trimmer can reach the target voltage or understatement.
What value of resistance I have to use for testing?. My goals are 5V and 15V.
0.7V is across R201? If yes this is 465mA CCS setting. If your dummy load draws more current your output voltage will sag.
For 5V R203=100Ω + 500Ω trimmer and for 15V R203=2.7kΩ + 500Ω trimmer worked for me.
Yes. CCS=465mA dummy load 33r I=V/R 15/33=455mA
very fair
Ok, I understand that if the resistance of the dummy load consumes more intensity produced by the regulator, the output current sag.
I think I have to adjust my dummy load resistors. They are on the verge of intensity produced by the regulator as RX01,
Now I see clearer
Well said. As well as Johnny Nash would have put it.
P.S. Use dummy as much as your real load idle will need. Is it 200mA @ 15V? Use 75R dummy. Or string two 33R in series you already got and make one 66R. Explained in the guide. So you can simulate what heat will go to the sinks, and set voltage, and watch it for a while away from the real circuit and be sure and safe before applying. The 1.5R can be +tolerance or getting higher when warmer, so you could very easily running 445-450mA in reality, sucked by the hungry dummy, leaving not a drop of lifeblood to the poor reg.
P.S. Use dummy as much as your real load idle will need. Is it 200mA @ 15V? Use 75R dummy. Or string two 33R in series you already got and make one 66R. Explained in the guide. So you can simulate what heat will go to the sinks, and set voltage, and watch it for a while away from the real circuit and be sure and safe before applying. The 1.5R can be +tolerance or getting higher when warmer, so you could very easily running 445-450mA in reality, sucked by the hungry dummy, leaving not a drop of lifeblood to the poor reg.
For 3.3v you need to build the BJT version. For 5V you can choose. Both BJT and Mosfet versions are working.
Have you read the Salas SSLV1.1 BIB boards guide?
BIB giude
Just finished...
Dialing in a MOSFET BiB 1.1 for the Buffalo II (with Tridents).
Vref is 2 green LEDs with 220R, and no trim-output voltage is stable at 5.35 VDC.
Achieved 583 mA in the CCS by jumping R306 (Salas says OK with low voltage regs) and 2R, 5W current setting resistor
Test load is 13R 5W, so load is ~410 mA at 5.35 VDC out.
D302-D304 are yellow.
Went with Silmic II 220 uF for Vref filter, and Nichicon Gold Tune, 10,000 UF for smoothing cap.
Looks like these values should be good starting points for anyone with the minikit parts wanting to power the B-II with tridents.
Dialing in a MOSFET BiB 1.1 for the Buffalo II (with Tridents).
Vref is 2 green LEDs with 220R, and no trim-output voltage is stable at 5.35 VDC.
Achieved 583 mA in the CCS by jumping R306 (Salas says OK with low voltage regs) and 2R, 5W current setting resistor
Test load is 13R 5W, so load is ~410 mA at 5.35 VDC out.
D302-D304 are yellow.
Went with Silmic II 220 uF for Vref filter, and Nichicon Gold Tune, 10,000 UF for smoothing cap.
Looks like these values should be good starting points for anyone with the minikit parts wanting to power the B-II with tridents.
I..
am sticking with the Silimic IIs for Vref. I am using Mundorf MKP (4.7uF) for the Zobel cap.
I have not done any listening with these, as I will need to do some re-drilling of my chassis, and a little other re-wiring (and probably a new difgital side transformer, as I need 2 x 9 Vac out for DAC and USB interface power). So it will be a little while before I do any listening. I have just been fine tuning for voltage and current. As the B-II is a popular devise, I just wanted to give people some starting points in values.
am sticking with the Silimic IIs for Vref. I am using Mundorf MKP (4.7uF) for the Zobel cap.
I have not done any listening with these, as I will need to do some re-drilling of my chassis, and a little other re-wiring (and probably a new difgital side transformer, as I need 2 x 9 Vac out for DAC and USB interface power). So it will be a little while before I do any listening. I have just been fine tuning for voltage and current. As the B-II is a popular devise, I just wanted to give people some starting points in values.