CM-42 Technical Description
PAGE 25 OF 38
SEM/CX-02:0076/DES A
Shut down sequence:
1.
To request a shutdown of the phone module, the application should provide an active low pulse with a
duration of 100 ± 25 ms on the HW_SD pin through an open collector output.
2.
This pulse is detected by the module, which confirms the request by enabling its HW_SD output, setting it
active low.
3.
The application waits for the HW_SD pin to become inactive high.
4.
The module has performed its power down sequence and disables its output resulting in HW_SD becoming
inactive high.
5.
The application shuts down, disabling MODULE_PWR_EN_B.
Figure 9: Shutdown Sequence Diagram
HW_SD
Shutdown
Request
Shutdown
Confirm
1
4
2
3
MODULE_
PWR_EN_B
5
