RT9941 Datasheet, PDF (1/33 Pages) Richtek Technology Corporation – Power Management ICs for Handheld Device

RT9941
Power Management ICs for Handheld Device
General Description
The RT9941 is a complete power management IC (PMIC)
for handheld device platform. This PMIC contains a fully
integrated linear charger for a single cell Lithium Ion battery,
five LDO linear regulators and two high efficiency buck
converters, a comparator, a reset and an I²C serial interface
to program one buck and one regulator output voltages as
well as power on timing control for complete flexibility.
The linear charger integrates LDO, MOSFET pass element
and thermal-regulation circuitry. The proprietary thermal-
regulation circuitry limits the die temperature when fast
charging or while exposed to high ambient temperatures,
allowing maximum charging current without damaging the
IC.
The two step-down converters are optimized for small size
inductor and high efficiency applications. They utilize a
proprietary hysteretic PWM control scheme that switches
with nearly fixed frequency and is adjustable, allowing the
customer to trade some efficiency for smaller external
component as desired.
The LDO linear regulators provide high power supply
rejection rate and have only 45μV_RMS of output noises for
100Hz to 10kHz frequency range to power noise sensitive
RF sections.
The RT9941 is available in WQFN-40L 5x5 package.
Ordering Information
RT9941
Note :
Package Type
QW : WQFN-40L 5x5 (W-Type)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Richtek products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
Features
z Charger
` Adapter & Battery Two Input with Auto Power
Dynamic Path.
` PWR_IN LDO support continuous 1.5A, peak 2A
current
` 4.5V to 5.5V Operation Voltage Range with Max.
Input 18V from PWR_IN Pin
` Switch Well for LDO and Charger Power MOSFET
` Set Charge Current by ISETA Pin
` Charge Status Indicator
` Interrupt for PWR_IN Plug In/Out Time Out and
Charger Done.
` Battery Temperature Monitoring
z Hysteretic Buck
` Buck 1 for DDR Memory, Adjustable Voltage and
600mA Output Current
` Buck 2 for PDN with 25mV/step I²C Adjustable
800mA Output Current
` Max. Efficiency Up to 90%
z LDO
` LDO1 : 3.3V/500mA for I/O, Default ON
` LDO2 : 1.2V/80mA for PLL, Default ON
` LDO3 : 1.2V/80mA for Pre-Core. I²C Adiustable,
Sync. with Buck2, Default ON
` LDO4 : 2.5V/50mA for AVDD of USB, ADC, TSC,
Default ON
` LDO5 : 3.3V/50mA for AVDD of USB, Default ON
` Minimize the External Component Counts
z Other
` System Reset
` Low Voltage Detector
` I²C Compatible Interface
` Power ON Timing Control
z RoHS Compliant and Halogen Free
Applications
z GPS and PDA
z Handheld Devices
DS9941-01 April 2011
www.richtek.com
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