Advertisement
criteria belo
ow in the US
SIM circuit de
Keep la
ayout of USI
IM card as c
200mm
m.
Keep U
USIM card si
ignal away f
Assure
the ground
between th
ground
and USIM_
_VDD no les
To avo
id cross-talk
k between
shield t
them with su
urrounded g
In orde
er to offer go
ood ESD pr
should
not be more
e than 50pF
and th
e USIM ca
ard so as to
protect
ion. The 33
3pFcapacitor
USIM p
peripheral ci
rcuit should
The pu
ll-up resisto
or on USIM_
and sen
nsitive occa
sion areapp
3.10. US
SB Interfa
ace
EC25 conta
ains one inte
egrated Univ
specification
n and suppo
orts high-sp
used for AT
T command,
data transm
upgrade. Th
he following
table shows
Table 10: U
USB Pin Des
scription
Pin Name
Pin No
o.
USB_DP
69
USB_DM
70
USB_VBU
US
71
GND
72
More details
s about the
USB 2.0 spe
The USB in
nterface is re
ecommende
figure show
ws the refere
nce circuit o
E
EC25-A_Us
All manuals and user guides at all-guides.com
esign:
close as pos
ssible to the
from RF and
d VBAT align
he module a
and the USIM
ss than 0.5m
mm to mainta
USIM_DATA
A and USIM
round.
rotection, it
is recomme
F. The 22oh
mresistors s
o suppress
the EMI s
rs are used
for filtering
be close to
the USIM c
_DATA line c
can improve
plied, and sh
hould be plac
versal Seria
al Bus (USB
eed (480Mb
bps) and ful
mission, GNS
SS NMEA s
s the pin def
finition of US
I/O
Desc
ription
IO
USB d
differential d
IO
USB d
differential d
Used
for detectin
PI
conne
ection.
Groun
nd
ecifications,
please visit
ed to be res
served for fi
of USB interf
face.
ser_ManualC
Confidentia
module. As
ssure the len
ngth of trace
nment.
M connecto
r short and
wide. Keep
ain the same
e electric po
otential.
M_CLK, kee
p them awa
ay with eac
ended to ad
d TVS whic
ch parasitic
should be ad
dded in seri
ies between
spurious tra
ansmission a
and enhanc
interferenc
ce of GSM90
00.Please n
connector.
anti-jammin
ng capability
y when long
ced close to
o the USIM c
connector.
) transceive
er which com
mplies with t
l-speed (12M
Mbps)mode
es. The USB
sentences ou
utput, softwa
are debug a
SB interface
e.
Comment
Require dif
data bus (po
ositive).
impedance
Require dif
data bus (mi
inus).
impedance
g the USB
Typical 5.0
t http://www.
.usb.org/hom
me.
rmware upg
grade in you
ur design. T
al / Release
d
34 / 6
69
L
LTE Module
e
EC25-AU
ser Manua
al
e is less than
n
the width o
of
ch other and
d
capacitance
e
n the module
e
ce the ESD
D
note that the
e
layout trace
e
the USB 2.0
0
B interface is
s
and firmware
e
fferential
e of 90Ω.
fferential
e of 90Ω.
0V
The following
g
Advertisement
