Maxim Integrated Products (Sunnyvale, CA) announced a new current-limited, switch-mode lithium-ion charger controller. The MAX1873R/S/T is designed to provide all of the functions needed to simplify and charge 23- or 4-series lithium-ion cells at up to 4A or more. It provides a regulated chargin current and voltage with less than 0.75 percent total voltage error at the battery terminals. An external p-channel MOSFET operates in a step-down dc/dc configuration to charge the batteries.
The MAX1873R/S/T regulates the battery-voltage and charging current using two control loops. An additional control loop limits current drawn from the input source. An analog voltage output proportional to charging current is also supplied.