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. The per-cell battery regulation voltage is set between 4.0V and 4.4V using standard 1% resistors. The number of cells is set from 1-to-4 by pin strapping. Battery temperature is monitored by an external thermistor to prevent charging outside the acceptable temperature range. The MAX1758 is available in a space-saving 28-pin SSOP package. Use the MAX1758EVKIT to help reduce design time. For a stand-alone charger with a 14V switch, refer to the MAX1757 data sheet. For a charger controller capable of up to 4A charging current, refer to the MAX1737 data sheet.
The MAX1758 is a switch‑mode lithium‑ion battery charger that can charge one to four cells. It provides regulated charging current up to 1.5 A and includes an internal high‑side switch, safety timer, and temperature monitoring.
The document lists electrical characteristics, absolute maximum ratings, pin functions, and recommended component values for designing a charger circuit, along with typical operating characteristics and timing information.
| Input Voltage Range (DCIN) | 6 V – 28 V |
|---|---|
| Output Voltage (VL) | 5.1 V – 5.7 V |
| Programmable Charge Current | Up to 1.5 A |
It can charge up to four Li+ cells.
The charger can be programmed for a maximum charge current of 1.5 A.
The device operates with an input voltage from 6 V to 28 V.