Integration Guide

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 Ta bl e 2-1.
Table 2-1: Module power states
State Details
Host is powered Module is powered USB interface active RF enabled
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
   