Pack-side battery fuel gauges for smart devices and portable medical equipment

Mouser now offers the MAX1720x and MAX1721x ModelGauge m5 battery fuel gauges from Maxim Integrated. These ultra-low power, stand-alone fuel gauge ICs feature low quiescent currents and programmable alert functions for voltage, temperature, current, and state of charge. The ICs implement the Maxim ModelGauge m5 algorithm without requiring host interaction for configuration, which makes the ICs ideally suited for pack-side battery fuel gauges in smartphones, tablets, portable medical devices, e-readers, and other handheld devices. As handheld devices become thinner, batteries are becoming smaller and capacity is increasing. These highly accurate battery fuel gauge ICs track battery usage in order to make efficient use of all available cell energy, extending battery life. These battery fuel gauges determine the amount of charge remaining in a battery and how much longer the battery can continue to provide useful power under the current load. The device algorithm combines the short-term accuracy and linearity, long-term stability, and temperature compensation to provide industry-leading fuel gauge accuracy. The ICs automatically compensate for cell ageing, temperature, and discharge rate, and provides accurate state of charge in milliampere-hours or percentage over a wide range of operating conditions. As the battery approaches the critical region near empty, the algorithm invokes a special error-correction mechanism that eliminates any error. These ICs are designed to monitor a single-cell pack while consuming just 18µA in active mode. They can monitor individual cells of a two-cell or three-cell pack or the entire stack voltage of any number of multiple-series cells, with an active-mode consumption of only 25µA. The ICs are available in a lead-free 3mm × 3mm, 14-pin TDFN package, and are supported by fully assembled and tested evaluation kits.