User's Manual
Table Of Contents
MC5720/5725/8755/8765 Hardware Integration Guide
10 2130114
Note: ESD protection is highly recommended for the SIM connector
at the point where the contacts are exposed, and any other signals
from the host interface that would be subjected to ESD by the user of
the end product.
Module power states
Note: The module unit defaults
to the Normal state when
VCC3.3 is first applied in the
absence of W_Disable# control.
Atanytime,themodulewillbeinoneoffourpowerstates:
• Disconnected
Nopowertothemodule.
• Off
Powertothemodule,butthemoduleispoweredoff.
• Normal
Themoduleisactive.Severalmodesarepossible(Receive,
Transmit,Sleep,Shutdown).
• Low power (“airplane mode”)
Themoduleisactive,butRFisdisabled.
Statemachinesareimplementedinthemoduletomonitorthe
powersupplyandoperatingtemperature.
Disconnected state
Note: The difference between
the Disconnected and Off states
is that in the Off state, the
module is still connected to the
power source and draws minimal
current.
Thisstateoccurswhenthereisnopowertothemodule—the
hostpowersourceisdisconnectedfromthemoduleandall
voltagesassociatedwiththemoduleareat0V.
Whetherthehostdeviceisalsopoweredoffdependsonthe
powerraildesign.Iftheconnectionbetweenthepowerrail
andthemoduleiscontrolledbythehost,thehostcanstay
poweredonandcutthepowertoputthemodemintothe
disconnectedstate.Ifthepowerrail
issharedbetweenthehost
deviceandthemodule,thehostispoweredoffwhenthe
moduleispoweredoff.
Off state
Inthisstate,thehostispoweredupandthemoduleis
powereddown(butstillconnectedtothepowersource).
Thehostkeepsthemodulepoweredoffbyasserting(driving
low)the
W_Disable#signal.Inthisstate,themoduledraws
minimalcurrent.