Abstract: In an embodiment, an electrical-line-noise canceller includes a phase detector, a phase lock loop, a zero-crossing detector, and an adaptive filter. The phase detector is configured to receive a composite input signal including an input neural signal combined with electrical line noise and to detect a phase of the electrical line noise. The phase lock loop is coupled to the phase detector and is configured to lock to the phase of the electrical line noise. The zero-crossing detector is coupled to the phase lock loop and is configured to detect zero crossings of an output of the phase lock loop. The adaptive filter is coupled to the zero-crossing detector and is configured to remove the electrical line noise from the composite input signal and output a filtered neural signal that is substantially similar to the input neural signal.