Skyworks has released a fully matched, three-stage power amplifier (PA) MMIC for small cells and massive MIMO antennas operating around 3.5 GHz. The SKY66313-11 has 100 MHz of instantaneous bandwidth, usable from 3.4 to 3.6 GHz, which enables the PA to support the n78 5G and B22 and B42 LTE bands.

With a 5 x 20 MHz, 8.5 dB PAR LTE signal and predistortion, the PA provide +23 dBm output power with less than −50 dBc ACLR. Without predistortion, the ACLR is typically −30 dBc. The power-added efficiency at +23 dBm output is typically 15 percent, with 37 dB gain. With a −20 dBm input signal, the typical input and out return loss are 14 and 16 dB, respectively.

Block diagram of the SKY66313-11
Block diagram of the SKY66313-11.

The PA requires a single 5 V bias and typically draws 115 mA quiescent current. Active biasing circuitry integrated on the MMIC compensates the PA’s performance for temperature, voltage and semiconductor process variations. The design includes on/off control, set with a 1.5 to 2.5 V control signal.

The SKY66313 is assembled in a 16-pin, 5 mm x 5 mm package, pin compatible with three other members of the PA family: SKY66312-11, covering bands B30 and B40; SKY66317-11, covering B7, B38 and B41; and SKY66315-11, covering n79.