SS Power Input Loading when disabled
Hi Jan.
I'm currently constructing a phono stage based on a Douglas Self design and a Silent Switcher (PCB 3.0b).
I'm planning to use a bank of four single 18650 cell power banks to feed the SS.
The SS has jumper J4 for an on/off switch which I think provides a disable rather than a disconnection function. Can you confirm this please?
The reason for the question is to determine whether the disabled SS might (slowly) drain the batteries whereas this would obviously not happen if completely disconnected.
Kind regards
Andy Chapman (UK)
The phoho design is detailed here:
The Signal Transfer Company: RIAA balanced output
Hi Jan.
I'm currently constructing a phono stage based on a Douglas Self design and a Silent Switcher (PCB 3.0b).
I'm planning to use a bank of four single 18650 cell power banks to feed the SS.
The SS has jumper J4 for an on/off switch which I think provides a disable rather than a disconnection function. Can you confirm this please?
The reason for the question is to determine whether the disabled SS might (slowly) drain the batteries whereas this would obviously not happen if completely disconnected.
Kind regards
Andy Chapman (UK)
The phoho design is detailed here:
The Signal Transfer Company: RIAA balanced output
I am using 18650's and SS -- be very careful with the Lithium ion cells as they can discharge an enormous number of electrons in a fraction of a second!
What is a reasonable wire length between the SS to the load?
I'm using the SilentSwitcher to power a phono preamp (50-60mA consumption), using 4 D-cell alkaline batteries which provide ~6.3V.
Due to constraints on my shelf the battery pack (in small case) needs to be placed about 2 ft away.
I can either put the SS in the preamp case and run 2* 2 ft from the batteries to the preamp case,
or place the SS with the battery pack and then run 3* 2ft wires to the preamp.
Any preferred route?
I'm using the SilentSwitcher to power a phono preamp (50-60mA consumption), using 4 D-cell alkaline batteries which provide ~6.3V.
Due to constraints on my shelf the battery pack (in small case) needs to be placed about 2 ft away.
I can either put the SS in the preamp case and run 2* 2 ft from the batteries to the preamp case,
or place the SS with the battery pack and then run 3* 2ft wires to the preamp.
Any preferred route?
Are there measurements for the 3.3V output? Maybe I misunderstood something but it did sound a bit like the 15V outputs were the "serious" ones and the 5v and 3.3V outputs were "simpler" with possibly different noise and bandwidth specs?
I need something to feed a reclocker and was wondering if the 3.3V output is suitable to supply clocks.
Thanks for any insights.
I need something to feed a reclocker and was wondering if the 3.3V output is suitable to supply clocks.
Thanks for any insights.
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Daniel, the +/-15V are extremely clean for analog circuitry. The 3.3V (and the 6.5 or 5V) are meant to support things like DAC clocks and are not as clean as the +/-15V outputs.
But the idea to use the 6.5V followed by something like a 3094 to get to 3.3V is excellent and will be a very good solution.
Jan
But the idea to use the 6.5V followed by something like a 3094 to get to 3.3V is excellent and will be a very good solution.
Jan
SilentSwitcher heat dissipation
Greetings all,
A friend and I are currently testing a SilentSwitcher to power the following from the +/-15V outputs; the 6.5/5/3.3V is not used:
The total estimated quiescent current is estimated to be: nominal, 240mA; maximum, 288mA (12 LM4562 on each board)
With a 9V input, the maximum current output from the +/- 15V was claimed to be 300mA here and, soon after that, revised to a more optimistic 480mA here, so this load would appear to be well within the limits.
After an hour of continuous operation, using an infrared thermometer, we find a temperature of about 70C in the area of C4, C5 and C6; these components appear to be the hottest in this area. The temperature elsewhere is not remarkable.
Is this normal?
Best regards.
Greetings all,
A friend and I are currently testing a SilentSwitcher to power the following from the +/-15V outputs; the 6.5/5/3.3V is not used:
- 2x Linkwitz Lab LX521 ASP.4 loudspeaker active crossover/equalizer boards
The total estimated quiescent current is estimated to be: nominal, 240mA; maximum, 288mA (12 LM4562 on each board)
With a 9V input, the maximum current output from the +/- 15V was claimed to be 300mA here and, soon after that, revised to a more optimistic 480mA here, so this load would appear to be well within the limits.
After an hour of continuous operation, using an infrared thermometer, we find a temperature of about 70C in the area of C4, C5 and C6; these components appear to be the hottest in this area. The temperature elsewhere is not remarkable.
Is this normal?
Best regards.
Jan,
Referencing to your excellent post here, I wanted to run some numbers by you.
I currently have a 5VDC @ 250mA power supply to use as the input supply of your Silent Switcher V3. Input is 1.25Watts and Output is therefore 1 Watt. 80% of Input V*I = Output V*I.
That means that my 5VDC @ 250mA power supply can deliver +/- 15VDC @ max 66mA, yes?
In the first scenario, I would like to power a small PCB that uses the THAT1200 chip. Power requirements for the THAT1200 are variable and flexible, i.e. anywhere from +/- 3VDC to +/-18VDC, typical current requirements @ +/-15VDC is ~ 5mA at idle. I have 2 of these boards. So I should be fine in this setup, even assuming some headroom right?
In the second scenario,I have another preamp PCB that can be supplied with +/- 8V DC to +/- 15VDC (max of +/- 18VDC). Quiescent current draw is 25 mA per PCB, since it has 3 opamps. Assuming we have to supply 50mA of current for a pair of PCB's will your Silent Switcher be okay with my 5V/250mA DC supply, assuming we need a little headroom as well?
Perhaps I should modify the Silent Switcher for +/- 8VDC or +/- 12VDC to eek out just a little bit more current?
Last questions: For J4 (the On/Off 2 pin header), if it is jumpered, is that the ON position? For the 3 pin header on the +/-15VDC output, do you know if a 3 position screw terminal block would fit?
Sorry for the pedestrian questions, just learning!
Best,
Anand.
Referencing to your excellent post here, I wanted to run some numbers by you.
I currently have a 5VDC @ 250mA power supply to use as the input supply of your Silent Switcher V3. Input is 1.25Watts and Output is therefore 1 Watt. 80% of Input V*I = Output V*I.
That means that my 5VDC @ 250mA power supply can deliver +/- 15VDC @ max 66mA, yes?
In the first scenario, I would like to power a small PCB that uses the THAT1200 chip. Power requirements for the THAT1200 are variable and flexible, i.e. anywhere from +/- 3VDC to +/-18VDC, typical current requirements @ +/-15VDC is ~ 5mA at idle. I have 2 of these boards. So I should be fine in this setup, even assuming some headroom right?
In the second scenario,I have another preamp PCB that can be supplied with +/- 8V DC to +/- 15VDC (max of +/- 18VDC). Quiescent current draw is 25 mA per PCB, since it has 3 opamps. Assuming we have to supply 50mA of current for a pair of PCB's will your Silent Switcher be okay with my 5V/250mA DC supply, assuming we need a little headroom as well?
Perhaps I should modify the Silent Switcher for +/- 8VDC or +/- 12VDC to eek out just a little bit more current?
Last questions: For J4 (the On/Off 2 pin header), if it is jumpered, is that the ON position? For the 3 pin header on the +/-15VDC output, do you know if a 3 position screw terminal block would fit?
Sorry for the pedestrian questions, just learning!
Best,
Anand.
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I currently have a 5VDC @ 250mA power supply to use as the input supply of your Silent Switcher V3. Input is 1.25Watts and Output is therefore 1 Watt. 80% of Input V*I = Output V*I.
That means that my 5VDC @ 250mA power supply can deliver +/- 15VDC @ max 66mA, yes?
The 1W seems OK, but 1W from a total of 30V would be 33mA, no?
In the second scenario,I have another preamp PCB that can be supplied with +/- 8V DC to +/- 15VDC (max of +/- 18VDC). Quiescent current draw is 25 mA per PCB, since it has 3 opamps. Assuming we have to supply 50mA of current for a pair of PCB's will your Silent Switcher be okay with my 5V/250mA DC supply, assuming we need a little headroom as well?
That will be tight with a 33mA capability.
Perhaps I should modify the Silent Switcher for +/- 8VDC or +/- 12VDC to eek out just a little bit more current?
Yes.
Last questions: For J4 (the On/Off 2 pin header), if it is jumpered, is that the ON position? For the 3 pin header on the +/-15VDC output, do you know if a 3 position screw terminal block would fit?
Yes, ON when jumpered. Simple on/off switch can be used here.
The header is on a 0.1inch pitch. Not sure about the physical space, those screw terminal blocks tend to be large.
Jan
That means that my 5VDC @ 250mA power supply can deliver +/- 15VDC @ max 66mA, yes?
The 1W seems OK, but 1W from a total of 30V would be 33mA, no?
In the second scenario,I have another preamp PCB that can be supplied with +/- 8V DC to +/- 15VDC (max of +/- 18VDC). Quiescent current draw is 25 mA per PCB, since it has 3 opamps. Assuming we have to supply 50mA of current for a pair of PCB's will your Silent Switcher be okay with my 5V/250mA DC supply, assuming we need a little headroom as well?
That will be tight with a 33mA capability.
Perhaps I should modify the Silent Switcher for +/- 8VDC or +/- 12VDC to eek out just a little bit more current?
Yes.
Last questions: For J4 (the On/Off 2 pin header), if it is jumpered, is that the ON position? For the 3 pin header on the +/-15VDC output, do you know if a 3 position screw terminal block would fit?
Yes, ON when jumpered. Simple on/off switch can be used here.
The header is on a 0.1inch pitch. Not sure about the physical space, those screw terminal blocks tend to be large.
Jan
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Thanks Jan!
Sorry I goofed on the total voltage! Yes +/- 15V is a total of 30V, so yeah, a small 33mA current capability will result. This should be fine for the THAT PCB board but I will still modify for +/- 8V on the Silent Switcher so I can get as much current as possible. About 63mA for each rail if modified to +/- 8V DC output I think.
Best,
Anand.
Sorry I goofed on the total voltage! Yes +/- 15V is a total of 30V, so yeah, a small 33mA current capability will result. This should be fine for the THAT PCB board but I will still modify for +/- 8V on the Silent Switcher so I can get as much current as possible. About 63mA for each rail if modified to +/- 8V DC output I think.
Best,
Anand.
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I'm not using anything now. But the 5V/250mA regulated supply is an auxiliary supply from a soft start board. It comes from a Meanwell IRM 2-05. The module does put out 400mA but there are other current requirements like relays etc...on the soft start board so only 250mA is available.
It would be nice just to use it instead of implementing another small transformer/rectifier/etc...
Best,
Anand.
It would be nice just to use it instead of implementing another small transformer/rectifier/etc...
Best,
Anand.