Nokia 300 - Microsd Card Interface; Usb; USB Interface

The SIM interface consists of an internal interface between RAPU and EM ASIC, and an external interface
between EM ASIC and SIM contacts.
Figure 13 SIM interface
The EM ASIC handles the detection of the SIM card. The detection method is based on the BSI line. Because of
the location of the SIM connector, removing the battery causes a quick power down of the SIM interface.
The SIM interface supports both 1.8V and 3.0V SIM cards. The SIM interface voltage is first 1.8 V when the SIM
card is inserted, and if the card does not response to the ATR (Answer to Request), a 3V interface voltage is
used.
MicroSD card interface
The microSD card interface has one internal interface between RAPU and EM ASIC and one external interface
between EM ASIC and the microSD card. The microSD card connector is mounted on a separate PWB, the Micro
PWB.
Figure 14 MicroSD card interface
USB
USB interface
The phone has an interface for USB (Universal Serial Bus). USB is a differential serial bus that provides a wired
connectivity between the phone and, for example, a PC or a headset.
RM-781
System Module
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