Telit Wireless Solutions 1vv0300773a Chipper User Manual


 
GE863-PRO
3
Hardware User Guide
1vv0300773a Rev. 0 - 24/01/08
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 18 of 64
TIP: For further documentation on ARM processor refer to ATMEL AT91SAM9260 datasheet
4 Hardware Commands
4.1 Turning ON the GE863-PRO
3
GSM/GPRS Engine
To turn on the GE863-PRO
3
GSM/GPRS engine the pad ON/OFF*-GSM must be tied low for at least 1
second and then released.
The maximum current that can be drained from the
ON/OFF*-GSM pad is 0,1 mA.
A simple circuit to do it is:
NOTE: don't use any pull up resistor on the ON# line, it is internally pulled up. Using pull up resistor may
bring to latch up problems on the GE863-PRO
3
power regulator and improper power on/off of the module.
The line ON# must be connected only in open collector configuration.
NOTE: In this document all the lines that are inverted, hence have active low signals are labeled with a
name that ends with a "*" or with a bar over the name.
NOTE: The GE863-PRO
3
turns fully on also by supplying power to the Charge pad (Module provided with a battery
on the VBATT pads).
TIP: To check if the device has powered on, the hardware line PWRMON should be monitored. After 900ms the line
raised up the device could be considered powered on.
PWRMON line rises up also when supplying power to the Charge pad
ON#
Power ON impulse
GND
R1
R2
Q1