Telit Wireless Solutions LM940 Design Guide

LM940 Hardware Design Guide
1VV0301352 Rev. 18 Page 4 of 75 2022-01-04
Not Subject to NDA
3.1.1. LM940 1.0 Pin-Out 18
3.1.2. LM940 2.0 Pin-Out 20
LM940 Signals That Must Be Connected 23
Pin Layout 24
4. POWER SUPPLY 26
Power Supply Requirements 26
Power Consumption 26
General Design Rules 27
4.3.1. Electrical Design Guidelines 27
4.3.1.1. + 5V Input Source Power Supply – Design Guidelines 27
4.3.2. Thermal Design Guidelines 27
4.3.3. Power Supply PCB Layout Guidelines 28
RTC 29
Reference Voltage 29
Internal LDO for GNSS Bias 30
5. ELECTRICAL SPECIFICATIONS 31
Absolute Maximum Ratings – Not Operational 31
Recommended Operating Conditions 31
6. DIGITAL SECTION 32
Logic Levels 32
6.1.1. 1.8V Pins – Absolute Maximum Ratings 32
6.1.2. 1.8V Standard GPIOs 32
6.1.3. 1.8V SIM Card Pins 33
6.1.4. 2.85V Pins – Absolute Maximum Ratings 33
6.1.5. SIM Card Pins@2.85V 33
Power On 33
6.2.1. Initialization and Activation State 34
Power Off 35
6.3.1. Graceful Shutdown 35
6.3.1.1. Graceful Shutdown by AT Command 35
6.3.2. Fast Shutdown 36

Telit Wireless Solutions LM940 Specifications

General

Brand	Telit Wireless Solutions
Model	LM940
Category	Wireless modules
Language	English