■ DESCRIPTION

The MB3889 is a symmetrical-phase type of two-channel, DC/DC converter IC using pulse width modulation (PWM) , incorporating an overcurrent protection circuit (requiring no current sense resistor) and an overvoltage protection circuit. Providing high output driving capabilities, the MB3889 is suitable for down-conversion.

■ FEATURES

• Built-in timer-latch overcurrent protection circuit (requiring no current sense resistor)

• Built-in timer-latch overvoltage protection circuit

• Synchronous rectification system providing high efficiency

• Power supply voltage range: 5.5 V to 18 V

• PWRGOOD terminals (open-drain) to output the protection status

• Symmetrical-phase system reducing the input capacitor loss

• Built-in channel control function

• Reference voltage: 3.5 V ± 1

• Error amplifier threshold voltage: 1.23 V ± 1 (0 °C to + 85 °C)

• Support for frequency setting using an external resistor (Frequency setting capacitor integrated)

• Oscillation frequency range: 100 kHz to 500 kHz

• Built-in circuit for load-independent soft-start and discharge control

• Built-in totem-pole output for Nch MOS FET