User Guide

CCS Technical Documentation System Module and User Interface
Company confidential RH-20
Issue 1 10/2003 Nokia Corporation. Page 31
The SIM interface is powered up when the SIMCardDet signal indicates "card in". This
signal is derived from the BSI signal.
The entire SIM interface locates in two chips: UPP and UEM.
The SIM interface in the UEM contains power up/down, port gating, card detect, data
receiving, ATR-counter, registers and level shifting buffers logic. The SIM interface is the
electrical interface between the Subscriber Identity Module Card (SIM Card) and mobile
phone (via UEM device).
The data communication between the card and the phone is asynchronous half duplex.
The clock supplied to the card is in GSM system 1.083 MHz or 3.25 MHz.
Figure 8: SIM interface RH-20
ACI
ACI is a point-to-point, bi-directional serial bus. ACI has two main features: 1)The inser-
tion and removal detection of an accessory device 2) acting as a data bus, intended
mainly for control purposes. A third function provided by ACI is to identify and authenti-
cate the specific accessory which is connected to the System interface.
Parameter Variable Min. Typ Max Unit
SIMCARDet, BSI comparator Threshold Vkey 1.94 2.1 2.26 V
SIMCARDet, BSI comparator Hysteresis (1) Vsimhyst 50 75 100 mV
UEM
UPP
C5 C6 C7
C1
C2
C3
SIMRst
SIMCl
k
SIMIO
VSIM
From
Battery
SIMIO
SIMClk
SIMR
t
SIM
SIMIF
register
UEM
digital
logic
BSI
UIF Block
CBusDa
CBusEnX
CBusClk
C8
C4
UEMInt
SIMIO
SIMCl
k
SIMRst
SIM
ASIP