Table of Contents
Advertisement
M20 Hardware Design
RI0
O
Ring indicator
DCD0
O
Data carrier detection
Serial Port 1
RXD1
I
Receiving data
TXD1
O
Transmitting data
RTS1
I
Request to send of serial
port1
CTS1
O
Clear to send of serial port1
SIM interface
PIN NAME
I/O
DESCRIPTION
SIM_VDD
O
Voltage supply for SIM card
SIM_DATA
I/O
SIM data
SIM_CLK
O
SIM clock
SIM_RST
O
SIM reset
SIM_PRESE
I
SIM card detection. Pulled
NCE
down internally.
M20_HD_V1.01
VOLmax=0.34V
VOHmin=2.0V
VOHmax= VDD_EXT
DC CHARACTERISTICS
The
voltage
can
selected
by
software
automatically, 1.8V or 3V
VIHmin=0.7*SIM_VDD
VOHmin=0.8*SIM_VDD
VOLmax=0.4V
When SIM_VDD=3V
VILmax=0.4V
When SIM_VDD=1.8V
VILmax=0.2* SIM_VDD
VOHmin=0.9*SIM_VDD
When SIM_VDD=3V
VOLmax=0.4V
When SIM_VDD=1.8V
VOLmax=0.2* SIM_VDD
VILmax=0.67V
VIHmin=1.7V
connect RTS0
pin to GND
directly.
If unused keep
these
pins
open.
If unused keep
these
pins
open.
These
two
pins
are
multiplex.
RTS1, CTS1
function is not
supported
in
default
firmware and
need
to
be
customized if
require.
If unused keep
these
pins
open.
COMMENT
be
All signals of
SIM interface
should
be
protected
against
ESD
with a TVS
diode array.
Maximum
trace
length
200mm from
the
module
pin to SIM
card holder.
If
SIM_PRESE
NCE
goes
- 21 -
Advertisement
Table of Contents
