User's Manual

Cinterion
®
ELS31-VA/ELS51-VA Hardware Interface Description
2.1 Application Interface
56
 ELS31-VA_ELS51-VA_HID_v01.000 2017-01-04
Confidential / Preliminary
Page 18 of 106
I
2
C I2CCLK IO V
OL
max = 0.45V
V
OH
min = 1.35V
V
OH
max = 1.85V
V
IL
max = 0.63V
V
IL
min = -0.3V
V
IH
min = 1.17V
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.
Minimum R external pull-
up (connected to V180
power supply) is 391
Ohms. The value of the
pull-up depends on the
capacitive load of the
whole system (I
2
C Slave
+ lines).
The maximum sink cur-
rent of I2CDAT and
I2CCLK is 4.6mA.
If lines are unused keep
lines open.
I2CDAT IO
SPI SPI_CLK O V
OL
max = 0.45V
V
OH
min = 1.35V
V
OH
max = 1.85V
V
IL
max = 0.63V
V
IL
min = -0.3V
V
IH
min = 1.17V
V
IH
max = 1.85V
If lines are unused keep
lines open.
By delivery default, the
SPI CS interface lines are
available as GPIO lines.
If configured as SPI lines,
the GPIO lines are
assigned as follows:
GPO26 --> SPI_CS1
GPIO27 --> SPI_CS2
SPI_MOSI O
SPI_MISO I
SPI_CS1
SPI_CS2
O
GPIO inter-
face
GPIO1-4
GPIO6-22
GPIO24,25,
27
IO V
OL
max = 0.45V
V
OH
min = 1.35V
V
OH
max = 1.85V
V
IL
max = 0.63V
V
IL
min = -0.3V
V
IH
min = 1.17V
V
IH
max = 1.85V
If unused keep line open.
Please note that some
GPIO lines are or can be
can be configured by AT
command for alternative
functions:
GPIO1-GPIO3: ASC0
control lines DTR0,
DCD0, and DSR0
GPIO4: FST_SHDN
GPO5: LED
GPIO8: Pulse Counter
GPIO16-GPIO19: ASC1,
HSIC control lines
GPIO20-GPO23: PCM/
I
2
S lines
GPIO24: ASC0 control
line RING0
GPO26-GPIO27: SPI CS
signals
GPO5,23,26 O
Table 2: Signal properties (Continued)
Function Signal name IO Signal form and level Comment