LGE Internal Use Only
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3. TECHNICAL BRIEF
- 29 -
3.5.4 PMIC Functional Block Diagram (U501 : PM6650-2M)
• Input power management
- Valid external supply attachment and removal detection
- Supports unregulated (closed-loop) external charger supplies and USB supplies as input power sources
- Supports lithium-ion main batteries
- Trickle, constant current, constant voltage, and pulsed charging of the main battery
- Supports coin cell backup battery (including charging)
- Battery voltage detectors with programmable thresholds
- VDD collapse protection
- Charger current regulation and real-time monitoring for over-current protection
- Charger transistor protection by power limit control
- Control drivers for two external pass transistors and one external battery MOSFET MOSFET is optional
- Voltage, current, and power control loops
- Automated recovery from sudden momentary power loss
• Output voltage regulation
- One boost (step-up) switched-mode power supply (SMPS) for driving white LEDs and hosting USBOTG
- Three buck (step-down) switched-mode power supplies that efficiently generate MSMC, MSME, and PA
(or second MSMC) supply voltages
- Supports dynamic voltage scaling (DVS) for MSMC and PA
- Eleven low dropout regulator circuits with programmable output voltages, implemented using three
different current ratings: 300 mA (two), 150 mA (six), and 50 mA (three). These can be used to power
MSMA, MSMP, RFRX1, RFRX2, RFTX, SYNT, TCXO, WLAN, MMC, USB, and RUIM circuits.
- All regulators can be individually enabled/disabled for power savings
- Low power mode available on MSMA and MSMP regulators
- All regulated outputs are derived from a common bandgap referenceclose tracking
• Integrated handset-level housekeeping functions reduces external parts count, size, cost
- Analog multiplexer selects from 8 internal and up to 18 external inputs
- Multiplexer outputs offset and gain are adjusted, increasing the effective ADC resolution
- Adjusted multiplexer output is buffered and routed to an MSM device ADC
- Dual oscillators -32.768 kHz off-chip crystal and on-chip RC assures MSM device sleep clock
- Crystal oscillator detector and automated switch-over upon lost oscillation
- Real time clock for tracking time and generating associated alarms
- On-chip adjustments minimize crystal oscillator frequency errors
- Circuits control TCXO warm-up and synchronize, deglitch, and buffer the TCXO signal
- TCXO buffer control for optimal QPH/catnap timing
- Three-stage over-temperature protection (smart thermal control)
• Integrated handset-level user interfaces
- Four programmable current sinks recommended as keypad backlight, LCD backlight,
camera flash, and general-purpose drivers
- Vibration motor driver programmable from 1.2 to 3.1V in 100 mV increments
- Speaker driver with programmable gain, turn-on time, and muting; differential operation
(drives external 8 Ω speakers with volume controlled 500 mW)
Summary of Contents for U990
Page 226: ...Note ...
Page 227: ...Note ...
