Description

MB39A125/126 is a DC/DC converter IC for charging Li-ion battery, suitable for down-conversion. It uses pulse width modulation (PWM) for controlling the output voltage and current independently. This IC integrates the build-in comparator for voltage detection of the AC adapter and automatically selects AC adapter or battery for power supply to the system.

Specifications and 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

Application Scenarios

This DC/DC converter IC, MB39A125/126, is widely used in various electronic devices that require charging Li-ion batteries. It is commonly applied in portable electronic devices, power banks, and other battery-powered devices.

Comparison

- High efficiency of 97% (MAX)

- Analog control of the charging current value

- Built-in AC adapter voltage detection function

- Soft-start circuit for smooth operation

- Output voltage setting accuracy may vary depending on the temperature