5.8.2 Module On & Off Sequence

Figure 5.8-1 shows typical powering-on and powering-off sequences, using the two optional hardware interfaces.

Figure 5.8-1 Typical Power-On & Power-Off Sequences

Event Description

AVCC is applied to the module, PON_L is pulled high internally

BPON_L is pulled low by the user application, initiating a power-on sequence

CVREF presence indicates a successful power-on initialization

DPON_L is pulled low by the user application, initiating a power-off sequence E VREF absence indicates network de-registration and shut-down complete F VCC can be safely removed

GVCC is applied to the module, PON_H is pulled low internally

HPON_H is pulled high & retained high, initiating a power-on sequence I VREF presence indicates a successful power-on initialization

J PON_H is released, initiating a power-off sequence

KVREF absence indicates network de-registration and shut-down complete L VCC can be safely removed

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