Differential IF 15 dB RF/IF amplifier achieves 50 dBm OIP3

January 29, 2013 // By Jean-Pierre Joosting
The LTC6430-15, from Linear Technology, is a 15 dB amplifier, which achieves high dynamic range in a 100 Ohm differential environment from 20 MHz to 1 GHz and beyond.

Two performance grades are available: at 240 MHz, the A-grade OIP3 is typically 50 dBm and is fully tested and guaranteed to be a minimum of 47 dBm; while the B-grade OIP3 is typically 47 dBm. Noise Figure is 3 dB, which corresponds to an input-referred amplifier noise of 1 nV/√Hz. DC power consumption is 800 mW. This combination of low noise and low distortion provides wide dynamic range needed for high performance intermediate frequency communications and CATV applications.

The LTC6430-15 is easy to use, it is unconditionally stable, and the input and output are internally matched to 100 Ohm differential. With greater than 2.75 Vp-p linear output swing, it is well suited for driving high speed, high performance ADCs. Two 1:2 baluns, DC blocking capacitors, and RF bias chokes are all that is needed externally to achieve a wideband 50 Ohm balanced amplifier in communications applications. With two 1:1.33 baluns, the LTC6430-15 can be used as a high fidelity 75 Ohm CATV amplifier. P1dB is typically 24 dBm.

The LTC6430-15 is available in a 4 mm x 4 mm QFN-24 package with exposed pad for best thermal performance and low inductance. It is specified for operation from -40°C to 85°C case temperature.