Accumulators that operate to fully or partially remove noise from a signal, including removing noise inserted into the signal by the accumulator itself. In some embodiments, an accumulator may be operated in a sampling phase and a transfer phase each time the accumulator samples an input signal. In some such embodiments, an op-amp of an accumulation circuit of the accumulator may be auto-zeroed during some or all of the sampling phases of an accumulation period. In some embodiments in which the op-amp is auto-zeroed during some or all of the sampling phases, the accumulation circuit may include a holding capacitor that, during an auto-zeroing process, holds a value output by the op-amp during a prior transfer phase. Including such a holding capacitor in an accumulator may reduce a voltage that the op-amp output rises following the auto-zero process, which may reduce a bandwidth and noise of the accumulation circuit.