Novatel HS 3001, Integration Manual

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A falling-edge on this Active-Low input will switch-ON or switch-OFF the module. The
firmware controlled OFF function will deregister the modem from the network before
shutting the modem OFF.
This input has a “weak pull-up” resistor internal to the module. If users want the modem to
automatically come on when power is applied, they can tie this line low.
If RTC Sleep is required, then the PON line must be floated to allow the internal resistor to
pull the line high.
Controlling the PON signal must only be performed by an open collector/open drain device. If
controlling this signal from a microprocessor’s I/O pin, the PON can be pulled low when the
I/O is configured to be an output and floated high by reconfiguring the pin to be an input.
The AT$OFFDLY Command controls the OFF Delay. A value of 0 disables the
PON line from turning the module off. 0 is the default value.
To enable the module to switch-OFF via PON you must set AT$OFFDLY to a
value other than 0. The valid range is 100 to 1000 milliseconds.
Internal Power Switch
The modem has an internal power switch that supplies the modem operating power when
ON.
Figure 4-7 Internal Power Switch