Hello to all,
I will go develop a symetric power regulator for amplifiers and would like to ear some advises or suggestions related to this.
Back in the days in "Shine7" used to have a PA100 stereo amp with a regulator board supplying the PA100 amps using LT1083 TO-247
regulator now obsolete and I really like that idea, now that I have my own PA100 and very recently develop a PA250 Lm3886
I am targetting developing a powerful regulator for this, in his page "Shine7" he also suggested a regulator using LM317 and
a series pass element tied to it but using it for positive and negative rails which seem to be good.
But here I aiming to isolate feedback loop from the output hopping to reduce possible instabilities, I am thinking
in using an high voltage power opamp driving some zener diodes in current source mode, my Idea to change voltages
is having dip switches or jumpers selecting the zeners which will set output voltages like for example +37/-37 +42/-42 +45/-45V.
I would like that the regulator be capable of delivering 20A with no effort with two output devices per rail which I am think using
Tip35/36 but would like here some suggestions also on this.
The main targets for this are a low part count, a limiting current of 20 Amp, a trip circuit for differential voltage between in/out that
would be higher than 7V and of course the stability.
Any suggestion that could help on this would be appreciated, I hope this resonate with more people D as this can be used not Just
with chip amps.
After all the thoughts I will actually develop the PCB for this regulator alongside with my other modules and make it available for
any one interested on this, if you want to check my work on other modules you can check here:
https://www.ebay.de/usr/rocksandsound
Regards
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Do you really need high precision? Do you care it is +-41v instead of +-42v?
If not, I would avoid NFB, just a zener diode followed with darlington or mosfet will work.
PS: Use CFP if you care low impedance.
If not, I would avoid NFB, just a zener diode followed with darlington or mosfet will work.
PS: Use CFP if you care low impedance.
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If you've got an op-amp in the system, why can't you just use a potentiometer to set the desired output voltage rather than have lots of zeners and jumpers? You only need one reference.
Also you're going to want a low-dropout solution to avoid excessive power dissipation at high currents.
A buck converter would do the job, but depends on how much space in your chassis so you can keep it away from the sensitive analog circuits.
Also you're going to want a low-dropout solution to avoid excessive power dissipation at high currents.
A buck converter would do the job, but depends on how much space in your chassis so you can keep it away from the sensitive analog circuits.
Hello, no I don't require high precision in the setting voltages, with mosfet a mosfet you would be thinking in NPN/PNP devices?
Pnp tend to have lower specs unless maybe with IXys parts.
Regards
On the regulator using a potentiometer yes is possible but in my opinion to users and after think on this for awhile if you are changing the voltages
for the desired output after you adjust one rail you would need to also try track it's negative symetric and trimmers are more prone to fail.
How only one reference this will use two op amps driving the zeners, one for the + side and another for - side.
LM3886 does use the same power line for the input/out stage so using a switching regulator is not an option beside the current involved, but I agree
that the amount in linear circuit would be a concern thats I mentioned to have a trip circuit that would activate if the differential between IN/OUT be
be higher than 7 volts, the space here depende on the user I just develop audio related electronics like this one for people use.
Regards
for the desired output after you adjust one rail you would need to also try track it's negative symetric and trimmers are more prone to fail.
How only one reference this will use two op amps driving the zeners, one for the + side and another for - side.
LM3886 does use the same power line for the input/out stage so using a switching regulator is not an option beside the current involved, but I agree
that the amount in linear circuit would be a concern thats I mentioned to have a trip circuit that would activate if the differential between IN/OUT be
be higher than 7 volts, the space here depende on the user I just develop audio related electronics like this one for people use.
Regards