Sierra Wireless AirPrime MC7455, Hardware Integration Manual

Page: 9 / 26

Rev 1 Sep.15 Proprietary and Confidential - Contents subject to change 9
2
2: Power
Power Supply
The host provides power to the MC7455 through multiple power and
ground pins. The host must provide safe and continuous power 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 MC7455 Product Technical Specification .
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 when VCC is first applied in the absence of W_DISABLE_N control
•
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
•
Number of active Tx time slots
   
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
·
If the module is currently configured to power on/off using W_DISABLE_N, the
host must issue AT!PCOFFEN=0 to configure the modem to enter low power
mode when W_DISABLE_N is asserted. Note: This is a persistent configu-
ration option.
·
Once the modem has been configured (AT!PCOFFEN=0), the host can assert
W_DISABLE_N to enter low power mode.
•
Automatically, when critical temperature or voltage trigger limits have been
reached
   