RT9953 4+1 CH Power Management IC General Description Features zz z zz One Synchronous Step-Up/Step-Down Selectable The RT9953 is a complete power supply solution for digital Converter still cameras and other handheld devices. The RT9953 is zz z zz Support 2AA or Li-ion Battery Applications a multi-CH power management IC including one zz z zz Internal Soft-Start Control synchronous step-up DC/DC converter, one selectable zz z zz 4 CHs with Internal Compensation synchronous step-up/step-down DC/DC converter, two zz z zz Power Switches Integrated synchronous step-down DC/DC converters, and one low zz z zz Up to 95% Efficiency dropout linear regulator. zz z zz 100% (max) Duty Cycle for Step-Down Converter The RT9953 is designed to fulfill the applications for DSC zz z zz Adjustable Output Voltage as follows : zz z zz Fixed 1MHz Switching Frequency CH1 is a synchronous step-up output for motor or DSC zz z zz LDO Works with Low-ESR Ceramic Capacitors system I/O power zz z zz Fast Line/Load Transient Response zz z zz High PSRR Linear Regulator CH2 is a selectable synchronous step-up/step-down zz z zz RoHS Compliant and Halogen Free output for motor or DSC system I/O power CH3 and CH4 are synchronous step-down outputs for DSP Applications core and memory power supply z CMOS Digital Still Camera CH5 is a 500mA, low dropout, low noise linear regulator z CMOS DV with soft-start function. z Portable Devices The RT9953 is designed to support Li+ and 2AA battery applications. The selectable step-up/step-down converter Pin Configurations can be set by SEL pin. For the synchronous step-up and (TOP VIEW) step down converters, the efficiency can be up to 95%. The RT9953 provides over current protection, thermal 24 23 22 21 20 19 shutdown protection, over voltage and under voltage 1 18 LX1 LX2 protection to achieve complete protection. The RT9953 is 2 17 PVDD1 PVDD2 available in the WQFN-24L 4x4 package. EN3 3 16 VDDM GND 4 15 FB4 FB3 5 14 Ordering Information SS EN2 25 6 13 RT9953 PVDD4 PVDD3 Package Type 7 89 10 11 12 QW : WQFN-24L 4x4 (W-Type) Lead Plating System G : Green (Halogen Free and Pb Free) Note : WQFN-24L 4x4 Richtek products are : RoHS compliant and compatible with the current require- Marking Information ments of IPC/JEDEC J-STD-020. For marking information, contact our sales representative Suitable for use in SnPb or Pb-free soldering processes. directly or through a Richtek distributor located in your area. DS9953-02 April 2011 www.richtek.com 1 LX4 EN1 EN5 GND VOUT5 FB1 FB5 FB2 PVDD5 EN4 LX3 SELRT9953 Typical Application Circuit For 2AA RT9953 L2 L1 2.2H 2.2H 1 18 V LX1 V LX2 BAT BAT C4 C1 10F 10F V 17 2 OUT CH2 V OUT CH1 PVDD1 PVDD2 5V 3.6V C2 C5 R3 C3 R1 10F x 2 10F x 2 470k 4.7pF 470k 22 21 FB1 FB2 R4 R2 88.7k 133k 6 13 3.6V PVDD4 PVDD3 3.6V C10 C7 10F 10F L4 L3 4.7H 4.7H V 7 12 V OUT CH4 OUT CH3 LX4 LX3 1.8V 2.5V C11 C8 C12 R7 C9 R5 10F 10F 33pF 470k 22pF 768k 4 15 FB4 FB3 R8 R6 374k 360k 19 V BAT SEL 11 16 PVDD5 3.6V 3.6V VDDM C13 C16 1F 1F 24 EN1 14 9 V OUT CH5 EN2 VOUT5 Chip Enable 2.5V 3 EN3 C14 C15 R9 1F 20 10pF 47k EN4 10 8 FB5 EN5 R10 23, 25 (Exposed Pad) 5 SS GND 22.1k C17 0.47nF www.richtek.com DS9953-02 April 2011 2