Motorola V820, Руководство по обслуживанию

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Theory of Operation
V810
2003 Motorola Confidential Proprietary Page 21
Battery Interface
The PM6000 (IC304) will be hardware configured for battery
charging, which the external charging power supply is expected to
provide the constant voltage and current regulation. Since CE Bus
charging accessories do not provide the current and voltage regulation
for charging lithium ion batteries, an external voltage/current control
circuit is required. Pass Transistor (Q303), Battery Transistor (IC306)
and Sense Resistor (R314,346) will provide the regulated voltage and
current that is required for charging lithium-ion batteries.
The Bipolar PNP Transistor is used for Pass Transistor (Q303) and the
P-channel MOSFET for Battery Transistor (IC306). The Sense
Resistor (R314,346) used for current monitoring and protection is 0.15
Ohm. The HKADC AD converter of PM6000 monitors charging
current, that is read and controlled by software.
Chargers for V810 are 2 types, mid-rate (400mA capable) and fast-rate
(1.5A capable). Those should be recognized by phone at initial insertion.
Charger is connected through CE bus connector pin 1(GND), 2
(BATTFDBK_RTS) and 3 (EXT_B+). Pin 3 is EXT_B+, main charging
current path and pin 2 is battery feedback and manual test multiplexed
signal. PM6000 will monitor battery voltage and charging current for
battery icon displaying normal phone operation, without a charger
attached
Power Distribution
Voltage regulation is provided by the PM6000 IC. The Low Dropout
Regulators output voltages can be controlled by the MSM through the
SBI. All of the LDO’s outputs can be enabled or disabled with the
LDO_ENABLE register, with the exception of the MSMP and MSMC
LDOs. There is no provision for the enabling or disabling the MSMP and
MSMC LDOs. The regulators and their load circuitries are described
below:
VREG_MSMC (1.867V) – MSM IC internal
VREG_MSMP (2.887V) – MSM Digital, Memory, Harness, USB
Transceiver, RFT6100, RFR6000, RFL6000
VREG_MSMA (2.6V) – MSM Analog
VREG_TCXO (2.85V) – TCXO supply, VCO
VREG_RF_RX (2.85V) – RFR6000, RFL6000
VREG_RF_TX (2.85V) – RFT6100, Temperature Sensor
VREG_SYNTH (2.85V) – RFT6100
B+ (3.6V) – PM6000
B+_PA (3.6V) – PAM(800/1900), LCD Backlight LED, Audio
AMP
VREG_LED – Keypad Backlight LED,
AUDIO CONTROL CIRCUITRY
Audio Line-up
The audio routing and gain control will be supported by MSM6050 IC.
With the integrated microphone and earpiece amplifiers, the MSM
interfaces directly to the microphone and earpiece and greatly reduces