MAX8934G

The MAX8934G dual-input Li+/Li-Poly linear battery charger with Smart Power Selector™ safely charges a single Li+/Li-Poly cell in accordance with JEITA* recommendations. The MAX8934G monitors the battery temperature (T_BATT) while charging, and automatically adjusts the fast-charge current and charge termination voltage as the battery temperature varies. The MAX8934G also monitors the battery temperature while the battery is discharging, and provides a warning flag (active-low OT) to the system in the event that the battery is over temperature. Safety region 2 is supported (see Figure 6 for details). An ultra-low I_Q, always-on LDO provides an additional 3.3V supply for system power.

The MAX8934G operates with either separate inputs for USB and AC adapter power, or from a single input that accepts both. All power switches for charging and switching the load between battery and external power are included on-chip. No external MOSFETs are required.

The MAX8934G features a Smart Power Selector to make the best use of limited USB or adapter power. Input current limit and battery charge current limit are independently set. Input power not used by the system charges the battery. Charge current limit and DC current limit can be set up to 1.5A and 2A, respectively, while USB input current can be set to 100mA or 500mA. Automatic input selection switches the system load from battery to external power.

The MAX8934G provides a SYS output voltage of 4.35V.

Other features include overvoltage protection (OVP), open-drain charge status and fault outputs, power-OK monitors, charge timers, and a battery thermistor monitor. Additionally, on-chip thermal limiting reduces the battery charge-rate to prevent charger overheating. The MAX8934G is available in a 28-pin, 4mm x 4mm, TQFN package.

Applications

• Digital Still Cameras and Digital Video Cameras
• Handheld Game Systems
• PDAs, Palmtop, and Wireless Handhelds
• Portable Media, MP3 Players, and PNDs