Temperature Monitoring State Machine - Sierra Wireless MC5725 Hardware Integration Manual

CDMA and GSM / UMTS Mini Card Hardware Integration Guide
Figure 2-3: Temperature monitoring state machine
Normal
mode
22
In the event of a discrepancy in values between this guide and the Product Specification Document (PSD), the PSD takes precedence.
3.

Temperature monitoring state machine

The module has a state machine to monitor the module's
temperature (Figure 2‐3).
current_temp <= TEMP_HI_NORM
current_temp > TEMP_HI_WARN
current_temp < TEMP_HI_NORM
current_temp < TEMP_LO_CRIT
current_temp > TEMP_NORM_LO
Table 2-2: Temperature trigger levels
TEMP_LO_CRIT
TEMP_NORM_LO
TEMP_HI_NORM
TEMP_HI_WARN
TEMP_HI_CRIT
1
Module-reported temperatures at the printed circuit board.
Temperature decreases from 10
and the module shield, and a further 10
shield and host environment (ambient), depending on the effi-
ciency of heat-dissipation in the host device.
Proprietary and Confidential
The host has the option, at this point, of driving
low (forcing the module to power off) to prevent damage
to the unit.
High Temperature
Critical
(Low power mode)
current_temp
> TEMP_HI_CRIT
High Temperature
Warning
Low Temperature
Critical
(Low power mode)
Condition MC57xx
Temp (°C)
-30
-20
85
95
108
W_Disable#
Host asserts
W_Disable#
Power off.
Handled by
Power State
state machine.
Host asserts
W_Disable#
1
MC87xx
Temp (°C)
-25
-15
85
95
108
° °
C–18 C between the PCB
° °
C–18 C between the
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