User's Manual
Table Of Contents
- Contents
- Figures
- Tables
- Document history
- Introduction
- Product concept
- GSM application interface
- GSM/GPRS operating modes
- Power supply
- Power up / down scenarios
- Automatic GPRS Multislot Class change
- Charging control of the GSM part
- Power saving
- Summary of state transitions (except SLEEP mode)
- RTC backup for GSM part of XT55/56
- Serial interfaces of the XT55/56 GSM part
- Audio interfaces
- SIM interface
- Control signals
- GPS application interface
- GSM and GPS antenna interfaces
- Electrical, reliability and radio characteristics
- Mechanics
- Reference approval
- Example applications
- List of parts and accessories
XT55/56 Hardware Interface Description
Confidential / Released
s
XT55/56_hd_v02.06a Page 24 of 125 17.12.2004
2.2 Circuit concept
The XT55/56 module comprises the following major functional components:
GSM / GPRS baseband block:
• Baseband controller operating at 26MHz
• Power supply ASIC
• Stacked Flash / SRAM
• Application interface (board-to-board connector)
GSM RF block:
• Skyworks RF transceiver
• Skyworks RF power amplifier / FEM
• RF front end (antenna connector)
GPS block:
• Processor type: ARM7/TDMI
• Processor speed: 25 MHz
GPS RF block:
• GPS receiver with SiRFstar Ile/LP chip set