Baseband Introductions - LG MG120a Service Manual

3.3 Baseband Introductions

3.3.1 Baseband Processor (AD6720 , U201)
• AD6720 is an ADI designed processor
• AD6720 consists of
1.Control Processor Subsystem including:
• 32-bit MCU ARM7TDMI Control Processor
• 39 MHz operation at 1.8V
• 1Mb of on-chip System SRAM Memory
2. DSP Subsystem including:
• 16-bit Fixed Point DSP Processor
• 91 MIPS at 1.8V
• Data and Program SRAM
• Program Instruction Cache
• Full Rate, Enhanced Full Rate and Half Rate
• Speech Encoding/Decoding
• Capable of Supporting AMR & PDC Speech Algorithms
3. Peripheral Functions
• Parallel and Serial Display Interface
• Keypad Interface
• Flash Memory Interface
• Page-Mode Flash Support
• 1.8V and 3.0V, 64 kbps SIM Interface
• Universal System Connector Interface
• Data Services Interface
• Battery Interface (e.g. Dallas)
4. Other
• Supports 13 MHz and 26 MHz Input Clocks
• 1.8V Typical Core Operating Voltages
• 289-Ball Package (12x12mm) , 0.65mm Ball pitch
5. The AD6720 baseband transmit section supports the following
• mobile station GMSK modulation power classes:
• GSM 900/850 power classes 4 and 5,
• DCS 1800 power classes 1 and 2, and
• PCS 1900 power classes 1 and 2
3.3.2 Interconnection with external devices
A. RTC block interface
Countered by external X-TAL
The X-TAL oscillates 32.768KHz
3. TECHNICAL BRIEF
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