The new HL5810 15GHz Limiting Amplifier is a is a thermally-compensated design which was intentionally developed for broadband pulse amplification and NRZ data transmission up to 20Gbps. In limiting mode, HL5810 produces a fixed 10Vpp output amplitude from an input amplitude range of 0.03Vpp to 0.63Vpp. While the HL8510 is not intended for PAM4 applications, the exceptional gain compression characteristics accelerate slow signal transitions and flatten topline aberrations, improving the signal integrity of binary data.  https://www.hyperlabs.com/product/hl5810/