Specifications

Cinterion
®
ELS81-US Hardware Interface Description
2.1 Application Interface
53
 els81-us_hid_v01.004 2017-09-27
Confidential / Preliminary
Page 20 of 107
1.8V SIM
Card Inter-
face
CCRST O V
OL
max = 0.25V at I = 1mA
V
OH
min = 1.45V at I = -1mA
V
OH
max = 1.90V
Maximum cable length or
copper track to SIM card
holder should not exceed
100mm.
CCIO I/O V
IL
max = 0.35V
V
IH
min = 1.25V
V
IH
max = 1.85V
V
OL
max = 0.25V at I = 1mA
V
OH
min = 1.50V at I = -1mA
V
OH
max = 1.85V
CCCLK O V
OL
max = 0.25V at I = 1mA
V
OH
min = 1.50V at I = -1mA
V
OH
max = 1.85V
CCVCC O V
O
min = 1.75V
V
O
typ = 1.80V
V
O
max = 1.85V
I
O
max = -30mA
I
2
C I2CCLK IO Open drain IO
V
OL
min = 0.35V at Imax = 4mA (Imax
= Imax external + I pull-up)
V
OH
max = 1.85V
R external pull up min = 560
V
IL
max = 0.35V
V
IH
min = 1.3V
V
IH
max = 1.85V
According to the I
2
C Bus
Specification Version 2.1
for the fast mode a rise
time of max. 300ns is per-
mitted. There is also a
maximum V
OL
=0.4V at
3mA specified.
The value of the pull-up
depends on the capaci-
tive load of the whole sys-
tem (I
2
C Slave + lines).
The maximum sink cur-
rent of I2CDAT and
I2CCLK is 4mA.
I
2
C interface of the mod-
ule already has internal
1KOhm pull up resistor to
V180 inside the module.
Please take this into con-
sideration during applica-
tion design.
If lines are unused keep
lines open.
I2CDAT IO
Table 2: Signal properties
Function Signal name IO Signal form and level Comment