The SKY77928-11 SkyLiTE™ Tx-Rx Front-End Module (FEM) offers a complete Power Amplifier (PA) and switching solution for advanced 2G/3G/4G cellular handsets with dual antenna.

Two PAs support quad-band GSM, GPRS, EDGE multi-slot operation and TD-SCDMA and TDD LTE transmission. The low band (LB) PA transmits in the GSM850/900 bands. The mid-band (MB) PA covers DCS1800, PCS1900, TD-SCDMA bands 34/39, and TDD LTE band 39. The FEM facilitates flexible broadband RF switch-through by means of 16 transmit/ receive (TRx) antenna switch ports covering all 3G/4G bands from 700 MHz through 2300-2700 MHz. In support of downlink inter-band Carrier Aggregation (CA), the TRx ports are partitioned into three independent switch blocks comprising 7 LB, 5 MB and 4 HB ports with strong M/H cross-band support. Each switch block includes a directional coupler that may be monitored on the CPL port with selectable forward or reverse directionality. A diplexer and a second antenna port provide flexible simultaneous L+M/HB reception required for downlink CA.

The SKY77928-11 includes a full set of features for state-of-the-art performance and minimal phone board complexity. The Heterojunction Bipolar Transistor (HBT) PA blocks are fabricated in Gallium Arsenide (GaAs). The HBT, switches, controller die, and passive components are mounted on a multi-layer laminate substrate. A plastic overmold encapsulates the entire assembly.

The CMOS controller provides PA band/mode selection and bias control, including the Mobile Industry Processor Interface (MIPI) RFFE logic and switch decoder circuitry. The PA controller provides VRAMP control of the GMSK envelope and reduces sensitivity to input drive, temperature, power supply, and process variations. Skyworks’ Finger-Based Integrated Power Amplifier Control (FB-iPAC) minimizes output power variation into mismatch. In EDGE and TD-SCDMA / TDD LTE linear modes, VRAMP voltage and MIPI-based bias settings jointly optimize PA linearity and efficiency.