Anyone have a simple schematic that can convert a single ended audio signal into a differential signal, but only using a single supply voltage (12V)?
Thanks.
Thanks.
Single supply is no problem, other than reducing the maximum signal output level.
See figure 3A here: https://sound-au.com/project87.htm
Use input and output 10uF capacitors, and bias the positive op amp inputs at +6V through 10k resistors.
Also use a decoupling capacitor between the +/- op amp supply pins.
See figure 3A here: https://sound-au.com/project87.htm
Use input and output 10uF capacitors, and bias the positive op amp inputs at +6V through 10k resistors.
Also use a decoupling capacitor between the +/- op amp supply pins.
A extremely professional way to do this would be like so (Courtesy : Analog Devices Inc.) The gain, as always, is given as |Rf/Ri|, controlled using only one resistor.
To operate the above circuit from a single power supply,
1) Do not use a coupling capacitor to block the standing DC from the input signal.
2) Apply a voltage equal to this DC to pin 5 (non-inverting input of bottom opamp), in place of the 75R resistor.
1) Do not use a coupling capacitor to block the standing DC from the input signal.
2) Apply a voltage equal to this DC to pin 5 (non-inverting input of bottom opamp), in place of the 75R resistor.
It assumes that the input already has some DC on it and yes, direct copy / paste may not work ...
Thanks. Any issue replacing the 2x100k resistors with 20k ones? Looks like the cutoff is still low, and would prefer to keep lower values if I can. I can simulate it too, all good. But just curious your thoughts. Thanks.
The 100k parts are just to keep the coupling capacitors charged to +6VDC, and their exact values are not critical,
other than their contributions to low frequency roll off. With 10uF capacitors, the total output loading should be >10k each.
other than their contributions to low frequency roll off. With 10uF capacitors, the total output loading should be >10k each.
I’ve been putting together a custom plate amp using TPA3255 (along with an entire 2.1 amplifier with active crossovers I’ve been building). The tps3255 needs differential inputs but I only have a single ended subwoofer output. I understand how to convert wifi two supplies, but using opamps with one supply always trips me up. So thanks for that.