■ DESCRIPTION

The MB3881 a step-up/step-down type of 8-channel, DC/DC converter IC. It uses pulse width modulation (PWM) and synchronous rectification, designed for low voltage, high efficiency, and compactness. This IC is ideal for down conversion and up/down conversion (employing a step-up/step-down Zeta system enabling free I/O setting). The MB3881 can use channel 8 as its own power supply to provide a wide range of supply voltages, allowing itself to operate at low voltage.

In addition, the MB3881 contains a triangular wave oscillator which can operate in synchronization with an external device, allowing the switching timing to be controlled externally. This contributes to reduction in switching noise, facilitating system configuration.

The MB3881 is designed to be compact using the LQFP-64P package whose body size is 7 × 7 mm.

The IC is the best for the power supply for advanced portable equipment such as a camera integrated VTR.

■ FEATURES

• Supporting the step-up/step-down Zeta methods (CH1 to CH7)

• Supporting synchronous rectification (CH1, CH2)

• Low start-up voltage : 1.8 V (CH8)

• Power-supply voltage range : 4 V to 13 V (CH1 to CH7)

• Built-in high-precision reference voltage generator : 2.5 V ± 1

• Oscillation frequency range : 100 kHz to 800 kHz

• Built-in triangular wave oscillator capable of external synchronization

• Error amplifier output for soft start (CH1 to CH4, CH7)