LG LG-UD90c, Service Manual

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LG-KG90C
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scrambled by the long code PN sequence of the user in order to ensure the confidentiality of calls.
Moreover, binary quadrature codes are used based on walsh functions in order to discern each
channel. Data created thus are 4-phase modulated by one pair of Pilot PN code and they are used to
create I and Q data.
When received, I and Q data are demodulated into symbols by the demodulator, and then
de-interleaved in reverse to the case of transmission. Then, the errors of data received from viterbi
decoder are detected and corrected. They are voice-decoded at the vocoder in order to output digital
voice data.
2.3.4 Memory Part
Memory part consists of 1 Gbits flash memory and 512 Mbits Static RAM. the Flash Memory part are
programs used for terminal operation. The programs can be changed through down loading after the
assembling of terminals. On the SRAM data generated during the terminal operation are stored
temporarily.
2.3.5 UIM Part
The MSM6100 is supports RUIM.
The UIM card contains the information of phone number, PIM data, SMS data, etc.
The whole circuits are designed to operate 3.00V UIM cards.
2.3.6 Power Supply Part
Turn On
When the battery voltage (2.7V ~ 5.5V) is fed and the PWR key of keypad is pressed,
PMIC(MAX1827) is activated by the PWR_ON_SW/ signal, and then the control signal PS_HOLD
signal is generated. And then, the regurator 1.85V_MSMC & 2.6V_MSMP, 2.6V_MSMA, are operated.
Operating
During the phone is on operating state,
PMIC(MAX1827) for MSM is always enable and gives the power MSM6100 and memory part
PMIC(MAX1827) for +3V_TX part is enabled on traffic state, and gives the power TX part devices.
LDO for +3V_RX part is enabled on idel state, and gives the power RX part devices.
Turn OFF
When the PWR key is pressed during a few seconds, PMIC(MAX1827) is turned on by
PWR_ON_SW/ and then, 'Low' is outputted on PS_HOLD. MSM6100 receives this signal and then,
recognizes that the POWER key has been pressed. During this time, MSM6100 outputs PS_HOLD as
low and turn off all devices
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