The MAX1758EAI+ is a stand-alone, switch-mode Li+ Battery Charger with internal 28V switch. The MAX1758 is a switch-mode lithium-ion (Li+) battery charger that charges one-to-four cells. It provides a regulated charging current accurate to ±10% and a regulated voltage with only a ±0.8% total voltage error at the battery terminals. The internal high-side switch delivers a programmable current of up to 1.5A to charge the battery. The built-in safety timer automatically terminates charging once the adjustable time limit has been reached. The MAX1758 regulates the voltage set point and charging current using two loops that work together to transition smoothly between voltage and current regulation. An additional control loop monitors the total current drawn from the input source (charging + system) and automatically reduces battery-charging current, preventing overload of the input supply and allowing the use of a low-cost wall adapter.
● Stand-alone charger for up to 4 Li+ batteries
● ±0.8% Battery regulation voltage accuracy
● Low-dropout 98% duty cycle
● Safely precharges near-dead cells
● Continuous voltage and temperature monitoring
● 0.1µA Shutdown battery current
● Safety timer prevents overcharging
● Input current limiting
● 300kHz PWM oscillator reduces noise
