RT9901

Features:

` 1.5V to 5.5V Battery Input Voltage Range
` Main step-up DC-DC Converter
*1.5V to 5.5V Adjustable Output Voltage
*Up to 90% Efficiency
*2.6A, 0.3 Internal Power Switch
` Two Step-Down DC-DC Converters
*0.8V to 5.5V Adjustable Output Voltage
*94% Efficiency
*100% Duty Cycle
` Step-up Charge Pump for Micro-Controller
` Build-in 0.8V Voltage Detector
` Up to 1.4MHz Switching Frequency
` 1A Supply Current in Shutdown Mode
` Programmable Soft Start Function
` Independent Enable Pin (CH1, CH2, CH3)
` External Compensation Network (CH1, CH2, CH3)
` Short Circuit Protection (CH1, CH2, CH3)
` Over Voltage Protection (CH2)
` 32-Lead VQFN Package
` RoHS Compliant and 100% Lead (Pb)-Free




Application

· Digital Still Camera
· PDAs
· Portable Device




Pinout






Specifications

` Supply Input Voltage (VDDM, VDD1, VDD2,VDD3,VDDC) ------------------------------−0.3 to 7V
` LX1 Pin Switch Voltage --------------------------------------------------------------- −0.3V to 7V
` LX2 Pin Switch Voltage -------------------------------------------------- −0.3V to (VDD2 + 0.3V)
` LX3 Pin Switch Voltage ---------------------------------------------------−0.3V to (VDD3 + 0.3V)
` CX Pin Switch Voltage --------------------------------------------------- −0.3V to (VDDC + 0.3V)
` Other I/O Pin Voltage ----------------------------------------------------−0.3V to (VDDM + 0.3V)
` Package Thermal Resistance
VQFN-32L 5x5, JA ----------------------------------------------------------------------- 34°C/W
` Lead Temperature (Soldering, 10 sec.) ---------------------------------------------------- 260°C
` Operation Temperature Range -------------------------------------------------- −40°C to 85°C
` Junction Temperature Range -------------------------------------------------------0°C to 125°C
` Storage Temperature Range ----------------------------------------------------−65°C to 150°C
` ESD Susceptibility
HBM (Human Body Mode) ---------------------------------------------------------------------- 2kV
MM (Machine Mode) --------------------------------------------------------------------------- 200V




Description

The RT9901 is a complete power-supply solution for digital still cameras and other hand-held devices. It integrates a high-efficiency main step-up DC-DC converter, two high-efficiency step-down converters, a charge pump, and voltage detector. The RT9901 is targeted for applications that use either two or three AA cells or a single lithiumion battery.
The main step-up DC-DC converter accepts inputs from 1.5V to 5.5V and build in 2.6A Internal switch. The two step-down DC-DC converters (CH2, CH3) accept inputs from 1.5V to 5.5V and regulate a resistor-adjustable output from 0.8V to 5.5V. Each DC-DC converters have independent shutdown inputs.
The feature of the charge pump is to deliver few current to micro-controller when the system operates in the standby mode. RT9901 include a low battery detector with 0.8V detection voltage. An adjustable operating frequency (up to 1.4MHZ) is utilized to get optimum size, cost, and efficiency.
RT9901 is available in VQFN-32L 5x5 package.