2 Precautions
This chapter describes the precautions for using the MS2131, especially for the user device or
host design. If not properly used, the MS2131 may not function normally and require design
changes on the host.
1. The MS2131 has strict peripheral power supply requirement. Strictly follow the design
requirements in Chapter 7 when designing the power supply circuits. Otherwise, cases
may occur that the board restarts in 2G large power events.
2. The MS2131 has its antennas embedded. Strictly follow the stacking design
requirements in section 5.4 "Antenna Design Requirements" when designing a host.
Otherwise, the antennas may deteriorate. As a result, exceptions, such as network access
fa ilures and call failures, may occur and adversely affect user experience.
Pay attention to the preceding precautions, especially for designing the host.