NCS35011 Battery Fuel Gauge

onsemi’s NCS35011 ultra-low power protection ICs manage lithium-ion batteries from three to five cells in series. They offer accurate battery voltage indication with up to five LED outputs.

Each cell in the battery pack is monitored for an overvoltage and undervoltage condition. Upon detecting an overvoltage, the ODI pin will assert to indicate a fault condition, and it will stay asserted until the fault is cleared. During an undervoltage condition, the UDI pin will also assert indicating the fault, but it will have a pulse width that is preset in the protector. Both overvoltage and undervoltage detections have a hard-coded preset delay time before fault indication. Pulling the ENB high will start a measurement of the battery pack voltage which will be compared to a preset detection threshold table. If a threshold voltage is exceeded, the protector will power the corresponding LED to indicate the charge state of the pack. Hardware protection and battery monitoring run autonomously, allowing operation without a microcontroller.

Features

• Overvoltage (OV) and undervoltage (UV) detection
• Protection for three, four, and five series cells
• State of charge (SoC) indication with high-voltage tolerant LED drivers
• Configurable fault outputs (active high or low for push-pull or open-drain)
• High-accuracy voltage measurement ±5 mV
• Low power consumption I_CC: 4 µA
• Input BAT voltage range 5 V to 25 V, tolerant to 65 V for increased immunity to surge
• Extended junction temperature range to +125°C

Applications

• Consumer products: primary or secondary protection
• Industrial products: secondary protection