Maxim Current-Sense Amplifier Delivers 1µA Supply Current For Battery-Powered Applications
Maxim Integrated Products introduced the MAX9610, a high-side, current-sense amplifier that provides precision monitoring for portable applications. Designed for battery-operated devices, the MAX9610 uses a precision input stage to achieve an extended, 1.6 to 5.5V input common-mode range (battery voltage). This input range is well suited for monitoring the current of a single-cell, lithium-ion (Li+) battery, which at full-charge is 4.2V, typically 3.6V in normal use, and less than 2.9V when ready to be recharged.
Additionally, the MAX9610 provides an ultra-low, 1µA supply current to extend battery life, and a low 500µV (max) VOS and ±0.5% (max) gain error for maximum precision. Available in tiny microDFN and SC70 packages, this high-accuracy device is suitable for monitoring USB ports and single-cell, Li+ batteries in cell phones, PDAs, and other portable electronics.
The MAX9610 is a voltage-output device and is offered in three gain options: 25V/V, 50V/V, and 100V/V. An external sense resistor can be used to set the maximum sense voltage at full-scale battery load current. For example, at 2A, a sense resistor of 25milliohms will give a Vsense of 50mV, and a gain of 50V/V will provide an output voltage of 2.5V, which is suitable for matching the input range of a typical ADC.
Fully specified over the -40 to +85°C extended temperature range, the MAX9610 is available in ultra-small, 1 x 1.5 x 0.8mm, 6-pin microDFN and 5-pin SC70 packages. Prices start at $0.64 (1000-up, FOB USA).
