Nisshinbo Micro Devices has introduced the NB7400, a high-precision secondary protection IC designed for 2- to 4-cell lithium-ion and lithium-polymer battery packs. The device provides an independent safety layer that detects overcharge conditions and can permanently interrupt the charging path via an external fuse when primary protection fails.
Nisshinbo NB7400 high-precision secondary protection IC for multicell batteries
Key Technical Specifications
- Supported cells: 2 to 4 series Li-ion / Li-polymer cells
- Maximum input voltage: 32 V
- Overcharge detection range: programmable from 4.20 V to 4.85 V
- Detection accuracy: ±20 mV
- Selectable delay times to prevent false triggering from noise
- Operating current: typically 2.5 µA (normal mode)
- Shutdown current: as low as 0.2 µA
- Integrated voltage regulator: 1.5 V to 3.3 V output with ±2% accuracy
- Package: compact DFN(PL)2020-8-GH
The NB7400 uses high-voltage-tolerant process technology and high-accuracy cell voltage monitoring. When an overcharge condition is detected, it activates an external fuse to permanently disconnect the charging path, providing an additional safety barrier for battery packs.
Target Applications
- Power tools
- Power banks and portable chargers
- Drones and UAVs
- Other multicell lithium battery-powered devices
With its combination of high precision, ultra-low power consumption and integrated regulation, the NB7400 helps designers improve battery safety while reducing component count in compact designs.
Source: Electronics For You