Hi, I know a muli-chip amp is not recommended for a first build but what considerations should I take if I want to copy Figure 17 from AN-1192?
What is the purpose of the LF412ACN?
In what cases would I use a positive and negative regulator? I know I can use two positive regulators in series.
I'm going to use a 250VA 25-0-25.
What is the purpose of the LF412ACN?
In what cases would I use a positive and negative regulator? I know I can use two positive regulators in series.
I'm going to use a 250VA 25-0-25.
plain simply you.. are best to first just build .. any simple amplifier.
its far too easy to mess upp BPA amps, and this project allso involves working with main's voltage, witch you should not if this is your first project.
its far too easy to mess upp BPA amps, and this project allso involves working with main's voltage, witch you should not if this is your first project.
I'm confortable working with mains voltage and I can follow a schematic without messing up. I don't have many chips to play with and I want to make something useful.
a schematic and a good pcb layout is not the same.
you see, the problem is that on a schematic for instance, a connection is an ideal wire that does not emitt anything, does not pick up anything, has no resistance, and a bunch of them do not have stray capacitance and so on.
on a pcb, a connection has all those properitys.
and you have 4 amplifiers, that are not 100% identical ever, and you have to make sure they do not fight eatch other, and do not oscillate in or out of aduible band.
for t bpa amp , the verry lest you want is an oscilloscope in the few mhz range, and verry proper knowledge of grounding techniques.
if you can get your hand on a decent bcp and you just want to solder it up it is likely to work, but with no former practice, i can mostly guarantee you the project will fail, and will be no more than wasted effort.
if.. you want to make something usefull, and accept my advice, then let us talk about your project first. Why the BPA amplifier, what are you going to drive with it?
what kind of power are you looking for, how many watts and why ?
most likely we gona find that you will be just fine with a mutch more simple chipamp that is not difficult to build, and you can manage your project with verry high chanses of making something usefull.
you see, the problem is that on a schematic for instance, a connection is an ideal wire that does not emitt anything, does not pick up anything, has no resistance, and a bunch of them do not have stray capacitance and so on.
on a pcb, a connection has all those properitys.
and you have 4 amplifiers, that are not 100% identical ever, and you have to make sure they do not fight eatch other, and do not oscillate in or out of aduible band.
for t bpa amp , the verry lest you want is an oscilloscope in the few mhz range, and verry proper knowledge of grounding techniques.
if you can get your hand on a decent bcp and you just want to solder it up it is likely to work, but with no former practice, i can mostly guarantee you the project will fail, and will be no more than wasted effort.
if.. you want to make something usefull, and accept my advice, then let us talk about your project first. Why the BPA amplifier, what are you going to drive with it?
what kind of power are you looking for, how many watts and why ?
most likely we gona find that you will be just fine with a mutch more simple chipamp that is not difficult to build, and you can manage your project with verry high chanses of making something usefull.
Thank you, yes I'm aware of that, I want to drive a 6Ω dual voice-coil subwoofer. 250VA is not plenty but it's all I can afford at this moment.
I want to be able to drive low impedance loads at around 100W of power, maybe I should just build a parallel 4780, my subwoofer isn't that powerful, what do you think of this pcb? I have some 3886s too.
I want to be able to drive low impedance loads at around 100W of power, maybe I should just build a parallel 4780, my subwoofer isn't that powerful, what do you think of this pcb? I have some 3886s too.
A dual voice coil driver allows one to use dual amplifiers.
Build a 60W lm3886 and check it thoroughly.
When you have debugged it and proved it is working properly, copy it to create a second channel.
Wire up the two channels to drive the two voice coils independantly.
Build a 60W lm3886 and check it thoroughly.
When you have debugged it and proved it is working properly, copy it to create a second channel.
Wire up the two channels to drive the two voice coils independantly.
The BPA200 should NOT be your first build ever. It doesn't matter how comfortable you are with mains voltage or how good you are at following a schematic. There are many ways to mess up even the simple LM3886 circuit. With the BPA200, you have at least 10x the potential for mishaps. Getting two LM3886es to play nicely in parallel is not easy.
I'm with Andrew here. Start with an LM3886 and make it work well. Then branch out from there.
Tom
PS: The LF412 is the DC servo.
I'm with Andrew here. Start with an LM3886 and make it work well. Then branch out from there.
Tom
PS: The LF412 is the DC servo.
if you really must ..
you can attempt the sta540 bpa amp.
the chip is the most foolproof i have yet came across.
1 chip holds 4 amplifiers, you can wire it up to bridge+paralell with the least efforth of bpa setups i know. actually i once for fun just ran one without any external components in bpa just to see if it works, and to my surprise as long as it was supplied from battery power it worked flawlessly.
2 of them would absolutely statify your demands, but i would still stick to something not BPA.
AndrewT made the possibly best solution for you.
if i was you i would go with his advice. even so i would purchase well known kits with decent pcb layout.
you can attempt the sta540 bpa amp.
the chip is the most foolproof i have yet came across.
1 chip holds 4 amplifiers, you can wire it up to bridge+paralell with the least efforth of bpa setups i know. actually i once for fun just ran one without any external components in bpa just to see if it works, and to my surprise as long as it was supplied from battery power it worked flawlessly.
2 of them would absolutely statify your demands, but i would still stick to something not BPA.
AndrewT made the possibly best solution for you.
if i was you i would go with his advice. even so i would purchase well known kits with decent pcb layout.
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