Fig. 1 Functional Block Diagram
The temperature stable ASNT5136-KMC SiGe IC provides low jitter broadband variable signal amplification between its input and output signal ports and is intended for use in high-speed communication systems. The circuit shown in Fig. 1 accepts an analog signal at its input differential port inp/inn and delivers a voltage-limited output signal at the output differential port outp/outn. The common-mode voltage levels of input signals can be adjusted using analog control inputs dcinp/dcinn. The total gain can be externally adjusted through the gain control port vgc. The input amplitude can be monitored using the analog output voltage pkdet.
The part’s I/Os support the CML logic 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 the specifications shown in the electrical characteristics section within the part’s datasheet. In the AC-coupling mode, the input termination provides the required common mode voltage automatically. The differential DC signaling mode is recommended for optimal performance.