LISA-U2 series - System integration manual
UBX-13001118 - R27
System description
Page 106 of 183
C1-Public
Reference
Description
Part Number - Manufacturer
J1
SIM Card Holder
CCM03-3013LFT R102 - C&K Components (or
equivalent)
R5
10 k
Ω
Resistor 0402 5% 0.1 W
Various manufacturers
R6
47 k
Ω
Resistor 0402 5% 0.1 W
Various manufacturers
R7
820
Ω
Resistor 0402 5% 0.1 W
Various manufacturers
DL1
LED Red SMT 0603
LTST-C190KRKT - Lite-on Technology Corporation
T1
NPN BJT Transistor
BC847 - Infineon
Table 43: Components for a GPIO application circuit
The recommended application circuit for the module status indication function, provided by LISA-U2
series module
GPIO1
and
GPIO13
pins to indicate module status (power-off mode, i.e. module
switched off, versus idle, active or connected mode, i.e. module switched on), is described in
The logic level of the pin configured to provide the module status indication, that is set high when the
module is switched on (with interfaces configured) and low when the module is switched off, is
inverted by a transistor biased by the
V_BCKP
supply, which is generated by the module when a valid
VCC
is applied.
A pull-down resistor is provided at the
GPIO1
output (which provides module status indication) to fix
a low level at inverting transistor input when
GPIO1
is floating, i.e. when the module is switched off,
so that high logic level is present at the application processor input when the module is switched off
and low logic level when the module is switched on (i.e. the opposite logic level of the GPIO).
1:1 scaling
Input (1.8V)
V_BCKP
2
LISA-U2 series
Application
processor
R1
R3
Module Status Indication
R2
20
GPIO1
T1
Figure 53: Module status indication application circuit
Reference
Description
Part Number - Manufacturer
R1, R3
47 k
Ω
Resistor 0402 5% 0.1 W
Various manufacturers
R2
100 k
Ω
Resistor 0402 5% 0.1 W
Various manufacturers
T1
NPN BJT Transistor
BC847 - Infineon
Table 44: Components for a module status indication application circuit
1.13
Reserved pins (RSVD)
LISA-U2 modules have pins reserved for future use. All the
RSVD
pins, except pin number
5
, can be
left unconnected on the application board.
☞
Pin
5
(
RSVD
) must be connected to GND.