The signal-detect block is used to detect an exit from electrical idle in the PCIe protocol. In the SATA protocol, the signal detect block is used to detect out of band (OOB) signaling. This block compares the magnitude of differential signals on the PS_MGTRRX pins with a specified reference and provides an output. This output is asserted in the presence of a differential signal greater than 175 mVPPD (PCIe) or 200 mVPPD (SATA) and deasserted in the presence of any signal less than 65 mVPPD (PCIe) or 75 mVPPD (SATA). The reference of comparison is programmable. The output is asserted during the reception of valid high-speed data but it can glitch because of high-frequency components in the data. A programmable digital filter is implemented to filter out such unwanted glitches.