RT9971 Datasheet, PDF (1/22 Pages) Richtek Technology Corporation – 7 CH Power Management IC

RT9971
7 CH Power Management IC
General Description
The RT9971 is a complete power supply solution for digital
still cameras and other hand held devices. The RT9971 is
a multi-channel power management IC including two step-
up DC/DC converters, two step-down DC/DC converters,
one selectable step-up/step-down DC/DC converter, one
inverting DC/DC converter and one WLED driver.
The RT9971 is designed to fulfill the applications for DSC
just as follows :
CH1 is a synchronous step-up output for motor or DSC
system I/O power
CH2 is a selectable synchronous step-up/step-down
output for motor or DSC system I/O power
CH3 and CH4 are synchronous step-down outputs for DSP
core and memory power supply
CH5 is a high voltage step-up output for CCD bias power
supply
CH6 is an inverting output for negative CCD bias power
supply
CH7 is a high voltage step-up output for driving WLED
For the CH2, the step-up or step-down converter, operation
mode can be selected by the SEL pin. Among all CHs,
there are 5 CHs with the built-in internal compensation.
The RT9971 also provides a transformerless inverting
converter for supplying the CCD power. For the
synchronous step-up and step down converters, the
efficiency can be up to 95%. The IC provides load
disconnection for CH 1 and CH 5. The IC has selectable
RTC_LDO/SW1 that can be determined by the CN pin.
The RT9971 is able to support Li-ion and 2AA battery
applications. The RT9971 provides WLED open protection,
current limit, thermal shutdown protection, over voltage
and under voltage protection to achieve complete
protection. The RT9971 is available in WQFN-40L 5x5
package.
Features
l One Synchronous Step-Up or Step-Down
Selectable Convertor
l Support 2AA or Li-ion Battery Applications
l Preset On/Off Sequence
l 5 CHs with Internal Compensation
l All Power Switches Integrated
l Up to 95% Efficiency
l 100% (max) Duty Cycle for Step-Down Converter
l Adjustable Output Voltage
l LED PWM Dimming Control
l LED Open Protection
l Transformerless Inverting Converter for CCD
l Fixed 1MHz Switching Frequency at CH1 to CH7
l RTC_LDO/SW1 Selectable by CN Pin
l 40-Lead WQFN Package
l RoHS Compliant and Halogen Free
Applications
l Digital Still Camera
l PDA
l Portable Device
Ordering Information
RT9971
Package Type
QW : WQFN-40L 5x5 (W-Type)
Note :
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.
DS9971-01 April 2011
www.richtek.com
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