This architecture offers many advantages for high-precision applications. The reference load impedance is constant and can be driven with an unbuffered reference or a slow, low-precision op-amp with no impact on static or dynamic performance. Since both terminals A and B are at the same ground potential, it is relatively easy to maintain matched switch impedances inside the chip, even in the presence of varying supply voltage and temperature. As a result, precision current-output R-2R DACs are available with excellent PSRR and temperature drift. In addition, since both amplifier inputs are always at ground, the common-mode rejection of the output amplifier is not critical. These DACs are sometimes used as variable-attenuators by applying a signal to the reference, in which case they are also referred to as multiplying DACs.