User Guide

NHM-8NX
System Module & UI PAMS Technical Documentation
Page 32 ãNokia Corporation Issue 1 05/02
The data communication between the card and the phone is asynchronous half duplex.
The clock supplied to the card is 3.25 MHz. The data baudrate is SIM card clock fre-
quency divided by 372 (by default), 64, 32 or 16. The protocol type, that is supported, is
T=0 (asynchronous half duplex character transmission as defined in ISO 7816-3).
Figure 7: UEM & UPP SIM connections
The internal clock frequency from UPP CTSI block is 13 MHz in GSM. Thus to achieve the
minimum starting SIMCardClk rate of 3.25 MHz (as is required by the authentication
procedure) and the duty cycle requirement of between 40% and 60% then the slowest
possible clock supplied to the SIM has to be in the GSM system clock rate of 13/4 MHz.
Internal Audio
Earpiece
The earpiece selected for NHM-8NX is the standard DCT3 13-mm earpiece from PSS
(previously used for 3210, 3310, 6210, 7110 among others). The earpiece design is leak
tolerant.
The internal earpiece is a dynamic earpiece with an impedance of 32 ohms. The earpiece
is a low impedance type, since the sound pressure is to be generated using current and
not voltage as the supply voltage is restricted to 2.7V. The earpiece is driven directly by
the UEM and the earpiece driver in UEM is a bridge amplifier.
UEM
UPP
C5 C6 C7
C1
C2
C3
SIMDATA
Data
SIMClk
SIMCLK
SIMIO
SIMRST
VSIM
From Battery Type
SIMIO
SIMClk
Data
GND
GND
SIM
SIMIF
register
UEM
digital
logic
BSI
UIF Block
CBusDa
CBusEnX
CBusClk
C8
C4
UEMInt