I built a little sub amp from a mono TPA3116D2 and a sub controller based around NE5532 op amps all in separate enclosures. The amp is powered by a 19VDC brick and the controller by 7812/7912 powered by a 12VAC wall wart. Since it works well, eventually I'd like to put both of those in a single case and power it from the 19VDC brick.
The amp would of course use the 19VDC supply but would also like to power the controller from this as well.
I can use a TLE2426 to obtain split rails or a op amp supply that was derived from a Silicon Chip article that I've used a couple of times (see schematic but disregard the voltages) to power the controller from the 19VDC supply. There's also ESP P43 but Rod states it should not be used on a shared supply.
Would there be any strange interactions using the supply for both or are there other alternatives?
The amp would of course use the 19VDC supply but would also like to power the controller from this as well.
I can use a TLE2426 to obtain split rails or a op amp supply that was derived from a Silicon Chip article that I've used a couple of times (see schematic but disregard the voltages) to power the controller from the 19VDC supply. There's also ESP P43 but Rod states it should not be used on a shared supply.
Would there be any strange interactions using the supply for both or are there other alternatives?
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An isolated DC-DC converter gets over the voltage offset issue: https://uk.farnell.com/tracopower/tec-2-2423/dc-dc-converter-2-o-p-2w/dp/2854899
Might need some more filtering to reduce the switching noise of course, but if you already have 7812 and 7912 to hand they could be used.
Can handle significantly more current than the 20mA TLE2426 on the 0V line of course, being a true split-rail supply.
Might need some more filtering to reduce the switching noise of course, but if you already have 7812 and 7912 to hand they could be used.
Can handle significantly more current than the 20mA TLE2426 on the 0V line of course, being a true split-rail supply.
Not to mention that the isolation would be tremendously helpful in avoiding the ground loop issues so commonly seen in shared supply setups.
For single supply operation, you can't just slap a rail splitter on an existing split supply board if your supply isn't floating. The whole circuit needs to be adapted with coupling caps e.g. in input, output and feedback and a Vcc/2 reference.
For single supply operation, you can't just slap a rail splitter on an existing split supply board if your supply isn't floating. The whole circuit needs to be adapted with coupling caps e.g. in input, output and feedback and a Vcc/2 reference.
Thanks for the comments. The Traco Power looks interesting and could only find the TMR series in Oz but not cheap at AU$41.15.
I did find another circuit which does away with split rails. It uses a 24VDC to power a Class D amp and an active filter circuit (supplies 18VDC, 0V to pins 8,4). For my use I would go 19VDC to 15VDC,0V to the op amps. Instead of the LM317 I'd just use a 7815 to keep it simple.
I did find another circuit which does away with split rails. It uses a 24VDC to power a Class D amp and an active filter circuit (supplies 18VDC, 0V to pins 8,4). For my use I would go 19VDC to 15VDC,0V to the op amps. Instead of the LM317 I'd just use a 7815 to keep it simple.
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You and me both. Too noisy to be of any use.
Ended up scrapping the idea and the woofer will have a passive filter and will add a volume control to the amp so I still end up with 1 case.
For split rails I've used ESP Project 43 with a lot of success but couldn't use it in this instance as it would share the power amp 24VDC supply.
Project 43 - Simple DC Adapter Power Supply
Ended up scrapping the idea and the woofer will have a passive filter and will add a volume control to the amp so I still end up with 1 case.
For split rails I've used ESP Project 43 with a lot of success but couldn't use it in this instance as it would share the power amp 24VDC supply.
Project 43 - Simple DC Adapter Power Supply
the person i bought the built in emi filtering dc-dc from sent me this link, which gave me hope and instructions if i need to add extra filtering. im hoping the power regulators on the tone board are enough filtering already with this dc-dc.
Preamp Nirvana..?
other wise i will give up if i cant get this to work and use a dedicated ± li-ion battery pack which i don't really want to do as it then means in years time when im older, tired, busy. i need time to replace the li-ion cells with new cells. by using 18650 cell holder things. i intend to make cell replacement very easy and quick. then i disconnect pack and use a rc charger to charge them. so battery i think should ideally be really big so i don't have to change it when using it all day at a event and to account for capacity loss over years. 3AH+ cells are around £3 from china each last i checked. don't pay more than that! I guess i would use 8x 3AH+ cells. need to do the math for what run time would be...
Preamp Nirvana..?
other wise i will give up if i cant get this to work and use a dedicated ± li-ion battery pack which i don't really want to do as it then means in years time when im older, tired, busy. i need time to replace the li-ion cells with new cells. by using 18650 cell holder things. i intend to make cell replacement very easy and quick. then i disconnect pack and use a rc charger to charge them. so battery i think should ideally be really big so i don't have to change it when using it all day at a event and to account for capacity loss over years. 3AH+ cells are around £3 from china each last i checked. don't pay more than that! I guess i would use 8x 3AH+ cells. need to do the math for what run time would be...
If you have a tone control board with on board regulators and rectifiers, then you can use a 12VAC wall wart for 12V regs (16VAC for 15V regs).
Only 2 wires (red + black) required for power in and gives a full wave voltage doubler type and the one in the pic uses 12VAC through recifier and 7812 + 7912 to give ±12VDC rails.
Only 2 wires (red + black) required for power in and gives a full wave voltage doubler type and the one in the pic uses 12VAC through recifier and 7812 + 7912 to give ±12VDC rails.
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thanks, ill have a read of that article.
thought maybe i should make the effort and post a link to the tone board i have. i have the previous version, quite similar AIYIMA Updated OPA2604 AD827JN OPAMP Stereo Preamp Pre amplifier Volume Tone Control Board|tone control board|volume tone control board|stereo preamp - AliExpress
thought maybe i should make the effort and post a link to the tone board i have. i have the previous version, quite similar AIYIMA Updated OPA2604 AD827JN OPAMP Stereo Preamp Pre amplifier Volume Tone Control Board|tone control board|volume tone control board|stereo preamp - AliExpress
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