Its for audio preamplifier . I have only 12vdc power supply . i would like to to split it to +-6VDC . what is the right way to do it ? thanks
"Its for audio preamplifier . I have only 12vdc power supply . i would like to to split it to +-6VDC .
what is the right way to do it ? "
That depends on exactly what the circuit of the 12V supply is.
Likely the best way is a "single supply" op amp circuit.
This would have the +12V on the positive op amp terminal, and the supply ground or common
on the negative op amp terminal. Some extra DC biasing parts are also necessary.
I suspect that this is what you really need.
what is the right way to do it ? "
That depends on exactly what the circuit of the 12V supply is.
Likely the best way is a "single supply" op amp circuit.
This would have the +12V on the positive op amp terminal, and the supply ground or common
on the negative op amp terminal. Some extra DC biasing parts are also necessary.
I suspect that this is what you really need.
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Then use this. Bear in mind the current limitations of the virtual ground.
TLE2426 3 terminal virtual ground rail splitter IC for split or dual power from single supply - YouTube
https://www.ti.com/lit/ds/symlink/t...=https%3A%2F%2Fwww.ti.com%2Fproduct%2FTLE2426
TLE2426 3 terminal virtual ground rail splitter IC for split or dual power from single supply - YouTube
https://www.ti.com/lit/ds/symlink/t...=https%3A%2F%2Fwww.ti.com%2Fproduct%2FTLE2426
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You can, but meeting certain conditions.
1) 12V supply is floating, not referenced to ground except by splitting resistors, and it feeds nothing else.
2) load current consumption is low, say 3-4 dual Op Amps (which are enough for preamp) , pulling 3-4 mA each.
3) lower splitting rsistors to, say, 10k or even better 4k7, so they can better equalize small rail consumption assymmetries, mainly becuse of processing non symmetrical signals.
Not a terrible "waste" of current because they will be passing, say, 10% tops 20% of what Op Amps "eat" at idle anyway.
1) 12V supply is floating, not referenced to ground except by splitting resistors, and it feeds nothing else.
2) load current consumption is low, say 3-4 dual Op Amps (which are enough for preamp) , pulling 3-4 mA each.
3) lower splitting rsistors to, say, 10k or even better 4k7, so they can better equalize small rail consumption assymmetries, mainly becuse of processing non symmetrical signals.
Not a terrible "waste" of current because they will be passing, say, 10% tops 20% of what Op Amps "eat" at idle anyway.
I would go with 1.2k ohm resistors to make the supply stiffer. They would only draw 5 mA across the 12 volt supply with power dissipation of 0.03 watts each. So 1/8 or 1/4 watt resistors could be used The power supply is a 2 amp supply.
A NE5532 draws a typical current of 8 mA with a maximum of 16 mA when idle.
A NE5532 draws a typical current of 8 mA with a maximum of 16 mA when idle.
Will this tle2426 can be OK to drive 9 opamp like 4558JRC ?
what is the limit of 20ma source/sink tell us ?
what is the limit of 20ma source/sink tell us ?
You don't have to split the supply to the 4558's, you have to split the ground reference for the negative input (feedback) and input signal. The op amp stops amplifying liniarly if the signal gets within 2 v of the + rail or the - rail. See on the datasheet the table "maximum voltage swing versus supply rails" chart. So nothin wrong with +12v as your op amp + supply, and "ground" as minus supply terminal of your op amp.
So you capacitativly couple your input & output signals, using say an $.08 electrolytic capacitor of 4.7 or 10 uf series the input. The capacitor to "ground" of the negative input, or positive in inverting configuration, the feedback terminal, goes to the "virtual ground", the resistor splitter of your supply shown in post 1. The input terminal of the op amp is pulled to this virtual ground by 100k or higher after the input capacitor.
While 100 k for the voltage splitter is a bit marginal for 9 4558 op amps, 1.2 kohm may be a bit of an overkill.
This arrangement on 12 v supply means your input signal should be limited to about 2 vac. Maybe 2.5.
Your output will oscillate around 6 vdc, so you have to capacitatively couple it to the output jack to keep from driving the input of the next device, an amp or mixer, crazy. Some amps or mixers will already have a capacitor on the input, but not all.
So you capacitativly couple your input & output signals, using say an $.08 electrolytic capacitor of 4.7 or 10 uf series the input. The capacitor to "ground" of the negative input, or positive in inverting configuration, the feedback terminal, goes to the "virtual ground", the resistor splitter of your supply shown in post 1. The input terminal of the op amp is pulled to this virtual ground by 100k or higher after the input capacitor.
While 100 k for the voltage splitter is a bit marginal for 9 4558 op amps, 1.2 kohm may be a bit of an overkill.
This arrangement on 12 v supply means your input signal should be limited to about 2 vac. Maybe 2.5.
Your output will oscillate around 6 vdc, so you have to capacitatively couple it to the output jack to keep from driving the input of the next device, an amp or mixer, crazy. Some amps or mixers will already have a capacitor on the input, but not all.
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It would be best to assume that the device you are connecting your design to is as terrible as it can be. Take the precautions you need, because relying on the next device in the chain to do that is just asking for issues in the future.