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SAMSUNG Proprietary-Contents may change without notice
Circuit Description
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2-5
VBAT33 via U618(XC6401EE27DR) which is a backup battery charging voltage,
VMICBAIS via UCD501(WM9712LEFL) which is a
MIC vias voltage,
VCAM15,VCAM-8,VCAM30,VCAM18 via U703(BD6020GU) which is a Camera voltage,
VCAM31 via U701(BH31FB1WHFV) which is a Camera voltage.
Backup Battery(ML1220-TT2)
The SGH-i750 has a back-up battery(ML1220-TT2) that stores data of SDRAM when the battery
removed or becomes low battery state that is below 2.8V.
The low battery state is checked by voltage detector or R3111Q281C(U607).
If the battery level is below 2.8V, nPOWER_FAIL signal is asserted. Then the backup DC/DC
converter(U603, MAX1676) output path is connected to VDD30 which is MPU, SDRAM voltage.
Backup battery supply main voltage or VDD30. If backup battery voltage is below 2V, discharging
path is disabled.
⑵
MPU & Memory part
MCP(UCP301:RTPXA270C5C416)
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ARM Architecture
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Built in Memory Controller, LCD Controller, AC97 Controller and MMC Controller
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Intel® PXA270 processor
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Clock and Power Controllers
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It has a variety of different system peripherals and controls all the peripheral circuitry.
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13x13mm VFBGA package
NAND FLASH Memory(UME402:MD4331-D1G-V3Q18-X)
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M-Systems Mobile Disk On Chip
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NAND-based flash technology that enables high dencity
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128MByte flash memory is used to store the PDA executable program and necessary data files.
SDRAM Memory(UME403:K4M513233E)
Samsung CMOS technology
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64MByte capacity Mobile Synchronous Dynamic RAM.
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It is used as a application program execution space, temporary data space to store the internal
flag information, timer data, and user data files.