■DESCRIPTION

MB39A125/126 is a DC/DC converter IC for charging Li-ion battery, which is suitable for down-conversion, and

uses pulse width modulation (PWM) for controlling the output voltage and current independently. This IC integrates the build-in comparator for the voltage detection of the ACadapter, and selects the AC adapter or battery auto matically for power supply to the system.

■FEATURES

• High efficiency : 97(MAX)

• Built-in two constant current control circuits

• Analog control of the charging current value (+INE1, +INE2 terminal)

• Built-in AC adapter voltage detection function (ACOK, XACOK terminal)

• External output voltage setting resistor : MB39A125

• Built-in output voltage setting resistor : MB39A126

• Built-in charge stop function at low VCC

• Output voltage setting accuracy : ±0.74(Ta = −10 °C to +85 °C) : MB39A125

: 12.6 V/16.8 V ±0.8(Ta = −10 °C to +85 °C) : MB39A126

• Built-in high accuracy current detection amplifier (±5) (At input voltage difference 100 mV) ,

(±15) (At input voltage difference 20 mV)

• In IC standby mode (Icc =0 µA Typ) , make output voltage setting resistor open to prevent inefficient current loss

• Built-in soft-start circuit

• Standby current : 0 µA (Typ)

• Totem-pole type output for Pch MOS FET