The MAX1909 evaluation kit is an accurate and efficient multichemistry battery charger. It can charge three or four series Li+ cells with a current up to 3A. Charge current and input-source current are adjustable using on-board potentiometers. The output voltage is set to 4.2V ✕ the number of series cells in the battery pack. The number of series cells is jumper-selectable. The output voltage is adjustable between 4V to 4.4V (✕ number of series cells) by installing two resistors. The EV kit provides outputs to monitor the AC adapter current and the presence of an AC adapter. The MAX1909 automatically selects the power path for supplying power to the system by controlling two external P-channel MOSFETs. This decision is made based on the presence of an AC adapter.
This document provides a quick start guide for the MAX1909 Evaluation Kit (EV kit), an accurate and efficient multichemistry battery charger capable of charging three or four series Li+ cells with a current up to 3A. The kit allows for adjustable charge and input-source currents using on-board potentiometers and features automatic selection of the system power source based on the presence of an AC adapter.
| Charge Current | Up to 3A |
|---|---|
| Input Voltage | +8V to +25V |
| Battery Voltage | Up to 17.6V |
| Chemistries | Li+, NiCd, and NiMH |
| Temperature Range | 0°C to +70°C |
A DC source capable of supplying sufficient voltage and current, a voltmeter, and a battery pack or load.
Enable the MAX1909 by installing the shunt on jumper JU2.
The default battery regulation voltage is 4.2V per cell.