MAX1555EZK

The MAX1555 charges a single-cell lithium-ion (Li+) battery from both USB* and AC adapter sources. It operates with no external FETs or diodes, and accept operating input voltages up to 7V. 

On-chip thermal limiting simplifies PC board layout and allows optimum charging rate without the thermal limits imposed by worst-case battery and input voltage. When the MAX1551 thermal limits are reached, the charger does not shut down, but progressively reduces charging current. 

The MAX1555 includes a POK-bar output to indicate when input power is present. The MAX1555 features a CHG-bar output to indicate charging.

With USB connected, but without DC power, charge current is set to 100mA (max). This allows charging from both powered and unpowered USB hubs with no port communication required. When DC power is connected, charging current is set at 280mA (typ). No input-blocking diodes are required to prevent battery drain. 

The MAX1555 is available in 5-pin thin SOT23 packages and operates over a -40°C to +85°C range.