Data Sheet

ADCA5191

THEORY OF OPERATION

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The ADCA5191 is a single-die, 1800 MHz differential cascode

amplifier fabricated on a linear gallium arsenide (GaAs), pHEMT

process. The device provides general-purpose linear gain suitable

for a wide range of applications.

When used with a recommended balun, the ADCA5191 can ach-

ieve a 5.2 dB noise figure at 1800 MHz (3.8 dB noise figure at 1218

MHz) while holding excellent linearity for extended spectrum line

extender input stage applications.

The device has suitable drive capability to overcome nominal inser-

tion losses introduced from automatic gain control and tilt functions.

The ADCA5191 can also serve as an output stage for the upstream

path at any DOCSIS 4.0 frequency split.

Depending on the application, the ADCA5191 can be biased from

5.0 V through 8.0 V with currents from 250 mA to 530 mA. Opti-

mized biasing for 5.0 V applications can be achieved with additional

bill of material (BOM) changes.