LEON-G100 / LEON-G200 - System Integration Manual
GSM.G1-HW-09002-G3
Preliminary
System description
Page 39 of 125
OUT
IN
LEON-G100 / LEON-G200
12.6 k
1.88 V
22
RESET_N
Application Processor
680 k
OUT
IN
LEON-G100 / LEON-G200
12.6 k
1.88 V
22
RESET_N
Application Processor
INPUT
INPUT
22 k
330 k
OUT
IN
LEON-G100 / LEON-G200
12.6 k
1.88 V
22
RESET_N
330 k
220
Ferrite Bead
47 pF
Ferrite Bead
47 pF
Ferrite Bead
47 pF
Figure 22: Application circuits to sense if the module is in the reset state
The
RESET_N
is set low by the module for 160 µs to indicate that an internal reset occurs.
The exact low level time interval depends on the implemented circuit, since the fall time of the
RESET_N
low
pulse depends on the pull-down value, which must be greater or equal to 680 k
Ω
.
For example, if LEON
RESET_N
pin is connected through a 680 k
Ω
pull-down resistor to an input pin of an
application processor in the 1.8 V domain (i.e. Vih = 0.7 x 1.8 V = 1.26 V, Vil = 0.3 x 1.8 V = 0.54 V), the low
level time interval will be ~145 µs, since the 680 k
Ω
pull-down forces a ~35 µs 100%-0% fall time, as illustrated
in the Figure 23.