1 Scope 1

2 References 1

3 Definitions, symbols and abbreviations 1

4 Module classification and communication modes 2

4.1 Overview 2

4.2 Communication modes and frequency bands 2

4.3 Module classification 3

5 Basic Functions Requirements 4

5.1 Management 4

5.1.1 Module Identification Management 4

5.1.2 Module Status Management 4

5.1.3 Software Downloading and Upgrading Management 4

5.1.4 Module Parameters Profile Management 4

5.2 SIM Card Functions 4

5.3 Debugging Function Requirements 5

6 Physical Form Factor Specifications 5

6.1 Module Layouts 5

6.1.1 CBS1618 5

6.1.2 CBM1620 6

6.1.3 CBM2024 6

6.1.4 CBB2426 7

6.2 Pad Size and Spacing 8

6.2.1 CBS1618 8

6.2.2 CBM1620 9

6.2.3 CBM2024 10

6.2.4 CBB2426 10

6.3 Pad Assignments 11

6.3.1 CBS1618 11

6.3.2 CBM1620 12

6.3.3 CBM2024 13

6.3.4 CBB2426 15

7 Technical requirements of electrical interface 17

7.1 Power supply interface 17

7.1.1 DC power supply interface 17

7.1.2 Data I/O interfaces voltage 17

7.1.3 RTC power supply interface 17

7.2 Module control and status interface 17

7.2.1 Power switch and status indication interface 17

7.2.2 Module reset interface 18

7.2.3 Module wakeup interface 18

7.2.4 The reference voltage of VDD output interface 18

7.3 RF interface 19

7.4 SIM interface 19

7.5 Data I/O interfaces 19

7.5.1 UART interface 19

7.5.2 GPIO interface 20

7.5.3 I2C interface 20

7.5.4 SPI interface 20

7.5.5 USB interface 20

7.6 Analog interface 21

7.6.1 ADC interface 21

7.7 Audio interface 21

7.7.1 PCM interface 21

7.7.2 I2S interface 21

8 Software technical requirements 21

8.1 AT minimum commands for SMS 22

8.2 AT minimum General commands 22

8.3 AT minimum commands for Network services 22

8.4 AT minimum commands for Mobile termination control and status 23

8.5 AT minimum commands for Mobile termination errors 23

8.6 AT minimum commands for packet domain 23

9 Performance requirements 24

9.1 Application processor capability 24

9.2 Storage 24

9.3 Temperature characteristics 24

9.4 Reliability 24