User Guide

Headset hook detection interface (XMICN) electrical characteristics
Description Min Typ Max Unit Notes
Hook detection
threshold 1
1.25 1.35 1.45 V Two fixed
thresholds
inside Retu.
Selectable by
SW
Hook detection
threshold 2
0.5 0.6 0.7 V
Hook detection
hysteresis
25 mV
Hook detection
pull ups
1 2 4 uA
Audio signal electrical characteristics
Description Parameter Typ Unit Notes
XMIC N Audio in 1 V
pp
DC Offset 2.5-2.78V
XMIC P Audio in 1 V
pp
DC Offset 2.5-2.78V
HSEAR N Audio out 1 V
pp
10Ω nominal serial
impedance
HSEAR P Audio out 1 V
pp
10Ω nominal serial
impedance
HSEAR R N Audio out 1 V
pp
10Ω nominal serial
impedance
Not connected in
mono
HSEAR R P Audio out 1 V
pp
10Ω nominal serial
impedance
Not connected in
mono
SIM IF connections
Pin Signal I/O Engine connection Notes
C1 SIMCLK Out Retu SIM1ClkC Clock signal to
SIM card
C2 SIMRST Out Retu SIM1Rst Reset signal to
SIM card
C3 VSIM Out Retu VSIM1 Supply voltage
to SIM card,
1.8V or 3.0V.
C5 SIMDATA In/Out Retu SIM1DaC Data input /
output
RM-42
Nokia Customer Care System Module
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