■ DESCRIPTION
The MB39A107 is a DC/DC converter IC suitable for down-conversion, using pulse-width modulation (PWM) charging and enabling output voltage to be set to any desired level from 1 cell to 4 cells.
The MB39A107 adopts output for Nch MOS drive of synchronous rectification type.
The MB39A107 can be used to monitor the current in an AC adapter or battery, as it contains a current amplifier that can set an offset voltage.
It can also be used for applications such as setting the charging voltages for 2 batteries.
The MB39A107 provides a broad power supply voltage range and low standby current as well as high efficiency, making it ideal for use as a built-in charging device in products such as notebook PC.

■ FEATURES
• Built-in low-current control circuits in two systems (supporting dynamically controlled charging)
• The charge current value can be analog controlled (+INE1 and +INE2 terminal)
• Built-in synchronous rectification system output for Nch MOS FET
• Built-in charge pump for driving high-side Nch MOS, providing 100% on-duty support
• Built-in AC adapter detection function
• Output voltage setting accuracy : 4.2 V ± 0.74 % (Ta = − 10 °C to + 85 °C)
• Built-in high accuracy current detection amplifier : ± 5 % (input voltage difference at 100 mV)
                                                                                : ±15 % (input voltage difference at 20 mV)
• Output voltage setting using external resistor : 1 cell to 4 cells
• Oscillation frequency range : 100 kHz to 1 MHz
• In standby mode, leave output voltage setting resistor open to prevent inefficient current loss.
• Built-in standby current function : 0 µA (Typ)
• Built-in soft-start function independent of loads