Sierra Wireless WISMO218 Modem User Manual


 
WA_DEV_W218_PTS_002 Rev 005 Page 67 of 109
Product Technical Specification &
Customer Design Guidelines
ON/~OFF Signal
The ON/~OFF pin is used to switch ON or switch OFF the WISMO218.
ON/~OFF signal is internally connected to the permanent 3.0V supply regulator inside the WISMO218
via a pull-up resistor. Once there is VBATT supply to the WISMO218, this 3.0V supply regulator will
be enabled and so the ON/~OFF signal is by default at HIGH level.
A LOW level signal has to be provided on the ON/~OFF pin to switch ON the WISMO218.
Caution: All external signals must be inactive when the WISMO218 is OFF to avoid any damage when starting
and to allow the WISMO218 to start and stop correctly.
Avoid using application MCU GPIO to directly control the ON/~OFF signal of the WISMO218; instead,
control this signal via an open collector switching transistor.
Features
Table 25. Electrical Characteristics of the ON/~OFF Signal
Parameter
I/O Type
Minimum
Typ.
Maximum
Unit
V
IH
2V8
2.4
-
3.0
V
V
IL
2V8
-
-
0.4
V
Pin Description
Table 26. ON/~OFF Signal Pin Descriptions
Signal
Pin Number
I/O
I/O Type
Description
ON/~OFF
37
I
2V8
WISMO218 Power ON/OFF