Battery Fuel Gauges

A battery fuel gauge, also known as a battery gas gauge, determines the state-of-charge (SOC) and state-of-health of a battery and predicts how much longer, under specific operating conditions, the battery can continue to provide power. Inadequate battery life and unreliable SOC reporting are some of the most common complaints about any battery-powered device. Highly accurate battery fuel gauges are needed to avoid surprise shutdowns and are a critical part of the user experience.

With over 20 years of experience developing battery gauge technology, our battery fuel gauges have been successfully used in over one billion devices. Our broad portfolio of battery fuel gauges are suitable for almost every application, with industry-leading features such as:

  • Highest accuracy SOC reporting, even for difficult conditions such as high loads and low temperatures.
  • Low quiescent current (IQ) battery fuel gauges—critical for low-power applications such as wearables
  • Strong SHA-256 authentication to prevent counterfeit battery packs
  • Integrated protection to reduce solution size and simplify battery pack design
  • Advanced features such as time-to-empty, time-to-full, battery age forecasting, and dynamic power to extend run-time of transient loads
  • No need for battery characterization (ModelGauge™ m5 EZ)
  • Easy manufacturability with short programming times and no need for calibration

These battery fuel gauges are ideal for use in popular applications such as wearables, Bluetooth® headsets, IoT devices, portable medical devices, mobile phones, tablets, industrial computers, and 2-in-1 computers.

Battery Fuel Gauges Parametric Search 

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Battery Fuel Gauges Featured Products

Stand-Alone ModelGauge m5 Fuel Gauges with SHA-256 Authentication EZ


Offers nonvolatile memory (NVM) for pack-side, single-cell or multi-cell applications.

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7µA 1-Cell Fuel Gauge with ModelGauge m5 EZ


Combines coulomb counting and voltage fuel gauging for highest SOC accuracy.

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3µA 1-Cell/2-Cell Fuel Gauge with ModelGauge


Smallest, lowest power fuel gauge with proven, voltage-only ModelGauge algorithm.

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ModelGauge Battery Fuel Gauges

Our patented ModelGauge algorithm provides the industry's best accuracy for reporting battery SOC. By eliminating the current-sense resistor and other external components, our ModelGauge battery fuel gauge ICs also save cost and space.

ModelGauge Fuel Gauges 

ModelGauge m5 Battery Fuel Gauges

Our patented ModelGauge m5 algorithm combines the excellent short-term accuracy and linearity of a coulomb counter, the long-term stability of a voltage-based ModelGauge battery fuel gauge, and temperature compensation to provide industry-leading fuel-gauge accuracy. In addition, as the battery approaches the critical region near empty, the ModelGauge m5 algorithm invokes a special error correction mechanism that eliminates any error. These battery gauge ICs provide accurate estimation of time-to-empty and time-to-full while charging, and three methods for reporting the age of the battery: reduction in capacity, increase in battery resistance, and cycle odometer.

Dynamic battery power technology enables the system to operate at peak performance by providing real-time information on the maximum power that the battery can deliver without violating the minimum system voltage requirement. At the same time, the algorithm enables the battery gas gauge to operate at very low quiescent current, which extends the operating life for small battery applications. Some versions include Cycle+™ age forecast and SHA-256 authentication to prevent the use of counterfeit batteries.

ModelGauge m5 EZ Battery Fuel Gauges 

ModelGauge m5 EZ Algorithm

The ModelGauge m5 EZ algorithm makes battery fuel gauge implementation easier by eliminating battery characterization requirements. The m5 EZ algorithm delivers highly accurate battery SOC, for most use cases, without requiring the usual lengthy battery characterization process, resulting in shorter design cycles. The robust algorithm also provides tolerance of battery diversity for most lithium batteries and applications.

ModelGauge m5 EZ Technology

Battery Fuel Gauges with Authentication and Protection

We also offer battery fuel gauge ICs with authentication and protection. Some devices integrate a battery gauge with a lithium-ion protector and a Secure Hash Algorithm-1 (SHA-1) or Secure Hash Algorithm-2 (SHA-2) based on the challenge-response authentication system.

Authentication and Protection Products 

Battery Gauge Analog Front-Ends (AFEs)

Our battery gauge AFEs are precision analog front-end ICs for measuring current, voltage, and temperature. On-chip temperature measurements eliminate the need for a thermistor in the battery pack. Our battery gauge AFEs can also use temperature data to enable gain and temperature-coefficient compensation in the current measurement, thereby allowing the use of a low-cost current-sense resistor.

Analog Front Ends (AFEs) 

Battery Fuel Gauges Design Resources

Technical Documents

Application Notes



Design Solution

Selector Guide