A 50-GHz-small-signal-bandwidth 50 GSa/s Track&Hold Amplifier in InP DHBT technology

A differential 50 GSa/s Track and Hold Amplifier with a large bandwidth and a high dynamic range is designed and fabricated with a 320 GHz-Ft-InP-DHBT process. Transient, S-parameters and spectral measurements are presented. For −4 dBm input power, spectral measurements in track mode give a THD and a SFDR of −56.3 dB and −57.3 dB respectively up to 3 GHz and −45.6 dB and −46.2 dB respectively up to 17 GHz. These measured THD are equivalent to 9 and 7.3 ENOB.