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The TDA20140 is an ultra-linear 8PSK satellite tuner that is intended for applications with challenging input power scenarios. It includes an integrated high-sensitivity LNA and a very large dynamic range. The device also includes a built-in RF Loop-Through (LPT).
TDA20140's built-in high-sensitivity LNA provides Noise Figure (NF) without the need for any external amplification. At the same time, the TDA20140's unique architecture allows it to achieve this NF for low-power signals without sacrificing linearity (IIP3, IIP2) when total power is high. The LNA includes multiple settings to allow power reduction when higher linearity is not required.
The tuner employs a fractional PLL that provides good phase noise while enabling a fine step size without adversely affecting lock time. Additional features include a built-in auto-tuning function, a single-ended RF input, and a buffered version of the crystal clock with optional dividers that is made available to drive companion ICs.
The device's flexible LPT includes a buffer and an attenuator with four settings. This allows flexibility when connected in cascade with a second satellite tuner. Good reverse isolation assures that interaction between the two tuners connected via the LPT path does not affect the desired signal.