Sierra Wireless AirPrime EM8805, Hardware Integration Manual

Page: 9 / 30

Rev 1 Jan.13 Proprietary and Confidential - Contents subject to change 9
2
2: Power
Power supply
The host provides power to the EM8805 through multiple power and
ground pins. The host must provide safe and continuous power (via
battery or a regulated power supply) at all times; the module does not
have an independent power supply, or protection circuits to guard
against electrical issues.
For detailed pinout and voltage / current requirements of this module,
see the
AirPrime EM8805 Product Technical Specification &
Customer Design Guidelines .
Module power states
The module has five power states, as described in Table 2-1 .
Table 2-1: Module power states
State Details
Host is powered Module i
s
po
we
red
USB interface ac
tive
RF ena
b
le
d
Normal
(Default
state)
•
Module is active
•
Default state. Occurs when VCC is first applied, Full_Card_Power_Off# is
deasserted (pulled high), and W_DISABLE#1 is deasserted
•
Module is capable of placing / receiving calls, or establishing data connections on the
wireless network
•
Current consumption is affected by several factors, including:
•
Radio band being used
•
Transmit power
•
Receive gain settings
•
Data rate
   
Low power
(‘Airplane
mode’)
•
Module is active
•
Module enters this state:
•
Under host interface control:
·
Host issues AT+CFUN=0 ( [1] AT Command Set for User Equipment (UE)
(Release 6) (Doc# 3GPP TS 27.007) )), or
·
Host asserts W_DISABLE#1, after AT!PCOFFEN=0 has been issued.
•
Automatically, when critical temperature or voltage trigger limits have been
reached))
   