hardware design v2.00
Table Of Contents
- Contents
- Version History
- 1 Introduction
- 2 SIM908 Overview
- 3 Package Information
- 4 GSM Application Interface
- 4.1 Power Supply
- 4.2 Power on/down Scenarios
- 4.3 Power Saving Mode
- 4.4 Charging Interface
- 4.5 RTC Backup
- 4.6 Serial Interfaces
- 4.7 Audio Interfaces
- 4.8 SIM Card Interface
- 4.9 LCD Display/SPI Interface
- 4.10 Keypad Interface
- 4.11 ADC
- 4.12 RI Behaviors
- 4.13 Network Status Indication
- 4.14 General Purpose Input/Output (GPIO)
- 4.15 PWM
- 4.16 I2C Bus
- 4.17 GSM Antenna Interface
- 5 GPS Application Interface
- 6 Electrical, Reliability and Radio Characteristics
- 6.1 Absolute Maximum Ratings
- 6.2 Recommended Operating Conditions
- 6.3 Digital Interface Characteristics
- 6.4 SIM Card Interface Characteristics
- 6.5 VDD_EXT Characteristics
- 6.6 SIM_VDD Characteristics
- 6.7 VRTC Characteristics
- 6.8 Current Consumption (VBAT = 3.8V, GPS engine is powered down)
- 6.9 Electro-Static Discharge
- 6.10 Radio Characteristics
- 6.11 Module label information
- Appendix
Smart Machine Smart Decision
SIM908_Hardware Design_V2.00 2012.05.07
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Table 2: GPS engine Performance
Performance
Parameter Description
Min Typ Max Unit
Horizontal Position
Accuracy
(a)
Autonomous 2.5 m
Speed - 0.01 - m/s
Velocity Accuracy
(b)
Heading - 0.01 - °
Hot start - 1 - s
Time To First Fix
(c)
Cold start - 30 - s
Autonomous
acquisition
-143 dBm
Sensitivity
Tracking -160 dBm
Channels 42
Update rate 1 Hz
Altitude 18288 km
Velocity 1850 km/h
Tracking L1,
CA Code
Receiver
Protocol support
NMEA,OSP
Continuous
tracking
76 mA
acquisition 77
Power consumption
(d)
Power down
current
0.03 uA
Table 3: Coding schemes and maximum net data rates over air interface
Coding scheme 1 timeslot 2 timeslot 4 timeslot
CS-1 9.05kbps 18.1kbps 36.2kbps
CS-2 13.4kbps 26.8kbps 53.6kbps
CS-3 15.6kbps 31.2kbps 62.4kbps
CS-4 21.4kbps 42.8kbps 85.6kbps