Fig. 1 Functional Block Diagram
The temperature-stable linear amplifier ASNT6142-BD, which is fabricated in an advanced SiGe technology, provides low-jitter broadband variable signal amplification between its input inp/inn and output outp/outn signal ports and is intended for use in high-speed communication systems. The gain adjustment is performed through an external control port vgc.
The part’s I/Os support the CML-type interface with on chip 50Ω termination to vcc and may be used differentially, AC/DC coupled, single-ended, or in any combination. In the DC-coupling mode, the input signal’s common mode voltage should comply with specifications shown in the electrical characteristics table within the part’s datasheet. In the AC-coupling mode, the input termination provides the required common mode voltage automatically. The on-chip peak detector delivers a single-ended output voltage pkdet proportional to the input signal’s amplitude. Additional control ports dcinp and dcinn can be used for the input common-mode voltage adjustment. For the optional output common-mode voltage adjustment, the output termination resistors can be connected to a separate positive supply voltage vcco instead of common ground, and the differential DC signaling mode is recommended for optimal performance.