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Ceramic Capacitor Compatible, Step-up DC/DC Controllers

■GENERAL DESCRIPTION

The XC9103/XC9104/XC9105 series are PWM, PWM/PFM auto switching /manual switching controlled universal step-up

DC/DC converter controllers.

will be required and phase compensation will be achieved. This allows the use of ceramic capacitors and enables to obtain lower

unnecessary.

With 0.9V internal voltage reference and by using externally connected two resistors, output voltage can be set freely within a

range of 1.5V to 30V. The series is available in 300 kHz and 180 kHz frequencies, the size of the external components can be

reduced. 100 kHz and 500 kHz are also available in custom options.

The XC9103 offers PWM operation. The XC9104 offers PWM/PFM automatic switching operation. The PWM operation is shifted to

the PFM operation automatically at light load so that it maintains high efficiency over a wide range of load currents. The XC9105

offers both PWM and PWM/PFM auto switching operations and it can be selected by external signal.

A current limiter circuit is built-in to the IC (except with the 500 kHz version) and monitors the ripple voltage on the FB pin.

Operation is shut down when the ripple voltage is more than 250mV. The operations of the IC can be returned to normal with

a toggle of the CE pin or by turning the power supply back on.

■APPLICATIONS

●PDAs

●Cellular phones

●Palmtop computers

●Portable audio systems

●Various multi-function power supplies

■TYPICAL APPLICATION CIRCUIT

■ TYPICAL PERFORMANCE

CHARACTERISTICS

☆GreenOperation Compatible

■FEATURES

Input Voltage Range

: 0.9V ~ 10V

Supply Voltage Range

: 1.8V ~ 10V

Output Voltage Range

: 1.5V ~ 30V

Set freely with the reference voltage

0.9V(±2.0%) and two resistors

Oscillation Frequency

: 100, 180, 300, 500kHz (±15%)

180, 300kHz only for XC9103/04/05B

type (with current limiter)

Output Current

: more than 400mA

Controls

: PWM (XC9103)

PWM/PFM auto-switching (XC9104)

PWM/PFM manual switching

(XC9105)

High Efficiency

: 85% (TYP.)

Stand-by Current

Load Capacitors

: Low ESR capacitors compatible

Current

Limiter Function

: Operates when

ripple voltage=250mV

Also available without current limiter

(100kHz and 500kHz types are

available only without current limiter)

Package

: SOT-25, USP-6B

ETR0404_003