Microwave Journal

Thermally Compensated Linear Amplifier: HL5887

May 11, 2023

HYPERLABS has developed a thermally compensated, ultra-linear 40 GHz amplifier/data driver targeted for use in high speed digital networks and telecom systems. The model HL5887 is a single-stage GaAs MMIC traveling wave amplifier (TWA) delivering 15 dB of gain over a bandwidth of 40 kHz to 40 GHz. The HL5887 data driver is specifically designed with a focus on 64 Gbps PAM4 data signaling applications. The HL5887 can also be used as a general-purpose gain stage in a variety of other applications where maintaining high pulse fidelity is important.

The HL5887 design leverages HYPERLABS’ broadband and time domain experience to provide a flat step response that translates to an accurate representation of the input signal. A flat pulse response is crucial for maintaining optimized eye diagrams while keeping the added jitter to a minimum. HYPERLABS has designed a proprietary thermal compensation algorithm into the amplifier that automatically adjusts the bias points of the amplifier to keep the amplitude and crossing point constant over a temperature range of 0°C to 60°C while maintaining a power dissipation of 1.6 W (typical). 

Utilizing proprietary techniques developed for HYPERLABS broadband bias tees and DC blocks, the TWA is internally biased, while the RF ports are AC-coupled to the user. Specific measures have been taken to incorporate power sequencing circuits that protect the TWA so that the external +6 and -8 V power supplies can be applied in any order. The HL5887 data driver housing measures 1.45 x 1.10 x 0.40 in. (36.8 x 27.9 x 10.2 mm).