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M
Module
USB_VBUS
USB_DM
USB_DP
GND
In order to m
meet USB d
data line sig
the module,
, and then th
hese resisto
be as short
as possible
.
In order to e
ensure the U
USB interfac
with the follo
owing princi
ples.
It is imp
portant to ro
ute the USB
of USB
B differential
trace is 90o
Do not
route signa
al traces un
importa
ant to route
the USB di
and low
wer layers bu
ut also right
Pay att
tention to the
e influence o
the cap
pacitance va
alue should b
Keep th
he ESD com
mponents as
NOTE
EC25 modu
ule can only
be used as
EC25-A_Us
E
All manuals and user guides at all-guides.com
Minimize
this stub
R3
NM_0R
NM_0R
R4
VDD
R1
R2
Close to M
Module
Figure 1
19: Referen
nce Circuit o
nal integrity
y, componen
ors should be
e placed clo
ce design co
orresponding
B signal trace
es as differe
ohm.
der crystals
s, oscillators
fferential tra
aces in inne
and left side
es.
of junction c
apacitance o
be less than
n 2pF.
s close as po
ossible to the
a slave dev
vice.
ser_ManualC
Confidentia
Test Poin
nts
ESD Array
y
0R
0R
of USB App
plication
nts R1, R2, R
R3 and R4 m
ose to each o
other. The e
g with the US
SB 2.0 spec
ential pairs w
with total gro
s, magnetic
devices and
er-layer with
ground shie
of ESD com
mponent on U
e USB conn
nector.
al / Release
d
35 / 6
LTE Module
L
e
EC25-AU
ser Manua
al
MCU
USB_DM
USB_DP
GND
must be pla
ced close to
o
extra stubs o
of trace mus
st
cification, ple
ease comply
y
ounding. The
e impedance
e
d RF signal
traces. It is
s
elding onno
ot only uppe
r
USB data lin
nes. Typically
y,
69
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