The SKY58100-31 Sky5® Multimode Multiband Tx-Rx Front-
End Module (FEM) supports 2G/3G/4G/5G mobile devices
and operates efficiently in 3G/4G/5G modes. The SKY58100-
31 is part of our Sky5® product portfolio. The FEM consists
of a low-band 3G/4G/5G PA block, low band and high-band
2G PA blocks, a silicon controller containing the MIPI RFFE
interface, RF band switches, antenna switches, a bi-directional
coupler, integrated filters for Bands 8, 5, and 28A, and
low noise amplifier (LNA). Extremely low leakage current
maximizes device standby time.
The IC die and passive components are mounted on a multilayer
laminate substrate. The assembly is encapsulated in a
7.6 mm x 6.0 mm x 0.75 mm, 56-pad MCM, SMT plastic
package which allows a highly manufacturable, low cost
The SKY58100-31 FEM is optimized for LTE Advanced which
utilizes Carrier Aggregation for higher data rates. The combined
filtering, RF matching and TRx switching internal to
the FEM optimizes performance for popular Downlink (DL)
CA band combinations in a compact and low-cost solution.
The FEM contains the necessary components between the
antenna and RFIC transceiver and is optimized to provide
superior Rx sensitivity and Tx efficiency.
Selecting the linear-GMSK operation standard disables
VRAMP input, so all PA biasing depends only on MIPI mode
selection. The transmitted envelope is then a linear function
of RF input.
Selecting VRAMP-enabled operation, the PA controller provides
VRAMP control of the GMSK envelope and reduces
sensitivity to input drive, temperature, power supply, and
process variations. The Skyworks Finger-Based Integrated
Power Amplifier Control (FB-iPAC) minimizes output power
variation into mismatch.
Exceptional RF coexistence planning and system techniques
are employed to minimize Rx de-sensitizing ("de-sense").