![background image](http://html1.mh-extra.com/html/telit-wireless-solutions/we865-dual/we865-dual_hardware-users-manual_1083823030.webp)
WE865-DUAL HW User Guide
1vv0300787
Rev. 1 - 03/10/08
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved
page 30 of 48
8.1 Power supply
When integrating the WE865-DUAL with the Telit GE863-PRO
3
module, as described in previous
chapters a 3.8V (typ) voltage must be provided to the WE865-DUAL.
The WE865-DUAL power enable signals (EN_A* and EN_B*) must be connected together and be
driven by the GE863-PRO
3
GPIO PC29 (ball F5) through a N-channel MOSFET.
In the GE863-PRO
3
the power supply inputs of the GSM engine and the ARM processor part have
been kept separate, VBATT is the input for the GSM part, VBATT2 is the input for ARM.
It is possible to connect together the two power inputs since they have compatible ranges, but if it is
desired the two power supplies can be kept separate.
If keeping separated VBATT and VBATT2 is the chosen solution, the WE865-DUAL 3.8V power balls
(VCC_A) should be connected to the same voltage source feeding VBATT2.
Figure 10
WE865-DUAL
EN_B*
EN_A*
GE863-PRO3
PC29
3V8 (typ)
3V8 (typ)
VBATT
VBATT2
3V8 (typ)
3V8 (typ)
GND
GND
VCC_A
VDD