Just wondering something, that I don't want to test, risking damaging the amp. After the DAC, I used a voltage follower, so that the amplifier wouldn't pull down the R-2R ladder. But then I wondered, if even with a voltage follower (op-amp montage, that doesn't change current?), what if the circuit doesn't have enough current to drive the amplififer? I mean, according to ohm's law, having an 8 ohm amplifer and 5 volts, I would need 0.625 A. Isn't that too much? Or the voltage follower is enough? I'm kind of confused here.

 

having an 8 ohm amplifer and 5 volts, I would need 0.625 A

8 ohms is the rated output load of the amplifier.
Th input impedance is much higher (likely in the neighborhood of 10kΩ) so the op amp should have no problem in driving that.