User's Manual
Table Of Contents
- Contents
- Tables
- Figures
- 1 Introduction
- 2 Interface Characteristics
- 2.1 Application Interface
- 2.1.1 Pad Assignment
- 2.1.2 Signal Properties
- 2.1.3 USB Interface
- 2.1.4 Serial Interface ASC0
- 2.1.5 Serial Interface ASC1
- 2.1.6 UICC/SIM/USIM Interface
- 2.1.7 Digital Audio Interface
- 2.1.8 Pulse Code Modulation Interface (PCM)
- 2.1.9 Inter IC Sound Interface (I2S)
- 2.1.10 GPIO Interface
- 2.1.11 I2C Interface
- 2.1.12 SPI Interface
- 2.1.13 Pulse Counter
- 2.1.14 HSIC Interface (ELS51-VA Only)
- 2.1.15 SDIO Interface (ELS51-VA Only)
- 2.1.16 Control Signals
- 2.2 RF Antenna Interface
- 2.3 Sample Application
- 2.1 Application Interface
- 3 Operating Characteristics
- 3.1 Operating Modes
- 3.2 Power Up/Power Down Scenarios
- 3.3 Power Saving
- 3.4 Power Supply
- 3.5 Operating Temperatures
- 3.6 Electrostatic Discharge
- 3.7 Blocking against RF on Interface Lines
- 3.8 Reliability Characteristics
- 4 Mechanical Dimensions, Mounting and Packaging
- 5 Regulatory and Type Approval Information
- 6 Document Information
- 7 Appendix
Cinterion
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ELS31-VA/ELS51-VA Hardware Interface Description
3.2 Power Up/Power Down Scenarios
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ELS31-VA_ELS51-VA_HID_v01.000 2017-01-04
Confidential / Preliminary
Page 63 of 106
3.2.4 Turn off ELS31-VA/ELS51-VA
To switch the module off the following procedures may be used:
• Software controlled shutdown procedure: Software controlled by sending an AT command
over the serial application interface. See Section 3.2.4.1.
• Hardware controlled shutdown procedure: Hardware controlled by employing the
FST_SHDN line. See Section 2.1.16.4.
• Automatic shutdown (software controlled): See Section 3.2.5
- Takes effect if ELS31-VA/ELS51-VA board temperature exceeds a critical limit.
3.2.4.1 Switch off ELS31-VA/ELS51-VA Using AT Command
The best and safest approach to powering down ELS31-VA/ELS51-VA is to issue the appropriate
AT command. This procedure lets
ELS31-VA/ELS51-VA log off from the network and allows the
software to enter into a secure state and safe data before disconnecting the power supply. The
mode is referred to as Power Down mode. In this mode. Before issueing the switch off AT com-
mand, the ON signal should be set to low (see Figure 34). Otherwise there might be back pow-
ering at the ON line in Power Down mode.
While
ELS31-VA/ELS51-VA is in Power Down mode the application interface is switched off and
must not be fed from any other voltage source. Therefore, your application must be designed
to avoid any current flow into any digital pads of the application interface.
Figure 34: Switch off behavior
BATT+
ON
VCORE
V180
AT^SMSO System power down procedure Power down
EMERG_RST