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GENERAL DESCRIPTION
The PT1302 is a compact, high efficiency, and low voltage step-up DC/DC converter with an Adaptive Current Mode PWM control loop. It comprises of an error amplifier, a ramp generator, a PWM comparator, a switch pass element and driver. It provides stable and high efficient operation over a wide range of load currents. It operates in stable waveforms without external compensation. The low start-up input voltage below 1V makes it suitable for 1~4 battery cells applications to provide up to 800mA output current. The 500KHz high switching rate reduces the size of external components. Besides, the 25μA low quiescent current together with high efficiency maintains long battery lifetime. The output voltage is set with two external resistors. Both internal 2A switch and driver for driving external power devices (NMOS or NPN) are provided.
FEATURES
¨ Low Quiescent (Switch-off) Supply Current: 25μA
¨ Low Start-up Input Voltage: 1.0V
¨ High Supply Capability: Deliver 5V 800mA with lithium cell/ 3.3V 800mA with 2Alkaline Cell
¨ Zero Shutdown Mode Supply Current
¨ High efficiency: 92%
¨ Fixed switching frequency: 500KHz
¨ Options for internal or external power switches
¨ MSOP-8 and SOT-89-5 packages are available
APPLICATION
¨ OLED, LCD Panel
¨ PDA, DSC, RF-Tags, MP3
¨ Portable instrument
¨ Wireless equipment
TYPICAL APPLICATION
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