BLU Products BLU DASH, Руководство по обслуживанию

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1.3.1 Transmitter
1) Low noise GMSK/8PSK/3G TX modulator eliminating external SAW filters, with
Direct-Frequency Modulation TX for GSM mode;
2) Dedicated Tx drivers can support radio configuration with multi-mode multi-Band Pas;
3) Excellent 3G EVM performance over the full Tx dynamic range;
4) High dynamic range integrated synchronous power detector, with ultra-fast TX power
control support;
5) Low Tx supply current form Vbat: 48mA(3G avg.DG09,BandI);36mA(GMSK DFM);
1.3.2 TX Part
1) High performance SAW-less(3G only)direct conversion receiver, with differential input
LNAs;
2) Receiver with superior sensitivity and blocking margins;
3) Low Rx supply current from Vbat: Typical 37mA(3G avg.DG09,BandI);
40mA(GSM/EDGE);;
1.3.3 Frequency Synthesizer
Fast settling synthesizers, with 26MHz internal DCXO or external VCTCXO reference.
1.4 Baseband and Logical Control Part
MTK baseband part is the core of the entire mobile phone control system; mainly
finish data signal that receive and transmit baseband signal process and complete
appliance system logical control, including RF part, battery management and charger part and
I/O port(include keypad scan, display, audio I/O, SIM card, COM download port and so on)
control and management.
1.4.1 Control and processing of RF part
1) When receive, the difference simulation baseband I/Q signal
（
IP
，
IN
，
QP
，
QN
）
received from RF part is GMSK demodulated that is A/D change to data signal by
baseband circuit. And then send to DSP to make digital signal process (including:
channel balance, decryption, deinterlearing, channel decode), decode voice to get
digital audio signal, make the signal digifax change D/A, simulation audio enlargement to
push receiver to make a sound.
2) When transmit, baseband circuit make simulation audio signal that microphone input
enlarge and filter and A/D change to become digital audio signal, and send signal to DSP
to make other process, including voice compression coding(FR, ERF, HR, AMR),
channel coding, interlacing, encrypt, channel balance and GMSK modulation, become
difference simulation baseband I/Q signal(IP
，
IN
，
QP
，
QN), and send RF part to process;
1.4.2 Power Management
The MT6573 built-in high performance power management IC, highly integrated
functions fulfill all power requirement in smart phone system. PMU block diagram see
Image 1-4-1:
1